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  • 2000-2004  (43)
  • 1985-1989  (6.619)
  • 1830-1839  (3.956)
  • Organic Chemistry  (7.448)
  • Engineering  (2.531)
  • Life Sciences  (639)
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  • 1
    Digitale Medien
    Digitale Medien
    Wastewater treatment by the HCR-processUpdated lecture from the 17 Annual Meeting of Biotechnologists (organized by the DECHEMA e.v.), Wiesbaden, 27-29 April 1999. (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 119-128 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The increasing requirements in wastewater treatment have led to the development of new wastewater treatment processes based on the know-how and experience in reaction and process engineering of the chemical industry. Due to their compactness, closed operation and high flexibility, these new processes show a large potential for process integration and significant cost reduction in particular for highly polluted industrial wastewaters.This paper discusses the HCR (high-performance compact reactor) - process, developed at the Mass Transfer Laboratory of the Technical University of Clausthal within the last decade. This process has been realized in more than 30 technical applications with a volume loading of up to 70 kg COD/m3 d and an energy consumption of about 0.4 kWh per kg CODelim.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200206
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  • 2
    Digitale Medien
    Digitale Medien
    Comprehensive cellulose chemistry. Weinheim, New York, Chichester, Brisbane, Singapore, Toronto: Wiley-VCH Verlag. Vol. 1: Fundamentals and Analytical Methods. XXII + 260 pages, 65 figures, 57 tables; DM 234.00. Vol. 2: Functionalization of Cellulose. XVI + 389 pages, 121 figures, 63 tables; DM 264.00. ISBN 3-527-29413-9. ISBN 3-527-29489-9 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 147-148 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200208
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  • 3
    Digitale Medien
    Digitale Medien
    Environmental interaction of Clays-Clays and the environment. Berlin, Heidelberg, New York, Barcelona, Budapest, Hong Kong, London, Milan, Paris, Singapore, Tokyo: Springer-Verlag. XIV + 271 pages, 74 figures, 10 tables; DM 128.00. ISBN 3-540-58738-1 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 160-160 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200210
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  • 4
    Digitale Medien
    Digitale Medien
    Variation revealed by RAPD-PCR profiles of microsymbiont Anabaena azollae strains from four N2 fixing Azolla cultures (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 169-174 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Nitrogen fixing Anabaena azollae strains isolated from four different Azolla cultures were characterized based on their total protein profile and RAPD profile to study the existing variation among them. As expected, the isolates showed almost similar protein banding patterns, but exhibited differences in 40-70 KDa protein subunits. Polymerase chain reaction of the DNA of the isolates, using four different primers, amplified specific sequences of DNA and showed clear polymorphism among the isolates. The RAPD profile generated the fingerprinting pattern characteristic of each strain based on the sequence of the primers used. Common band sharing observed between the strains A. azollae-RS-KK-SK-AM and A. azollae-RS-KK-SK-RP probably represents maternal inheritance of DNA to the progeny. The polymorphic bands were generated specifically for the isolates A. azollae-RS-KK-SK-RP and A. azollae-RS-KK-SK-AM with primers numbered 2 and 4, respectively, which could be developed as possible markers for these isolates.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200212
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  • 5
    Digitale Medien
    Digitale Medien
    Development of transgenic rice pure lines by particle bombardment-mediated transformation and genetic analysis-based selection (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 175-183 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Mature seed-derived callus from an elite Chinese japonica rice cv. Eyl 105 was transformed with a plasmid containing the selectable marker hygromycin phosphotransferase (hpt) and the reporter β-glucuronidase (gusA) genes via particle bombardment. After two rounds of selection on hygromycin (30 mg/l)-containing medium, resistant callus was transferred to hygromycin (30 mg/l)-containing regeneration medium for plant regeneration. Twenty-three independent transgenic rice plants were regenerated from 127 bombarded callus with a transformation frequency of 18.1%. All the transgenic plants contained both gusA and hpt genes, revealed by PCR/Southern blot analysis. GUS assay revealed 18 out of 23 plants (78.3%) proliferated on hygromycin-containing medium had GUS expression at various levels. Genetic analysis confirmed Mendelian segregation of transgenes in progeny. From R2 generations with their R1 parent plants showing 3:1 Mendelian segregation, we identified three independent homozygous transgenic rice lines. The homozygous lines were phenotypically normal and fertile compared to the control plants. We demonstrate that homozygous transgenic rice lines can be obtained via particle bombardment-mediated transformation and through genetic analysis-based selection.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200213
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  • 6
    Digitale Medien
    Digitale Medien
    Gentechnik, Biotechnik. Stuttgart: Wissenschaftliche Verlagsgesellschaft mbH, 632 pages, 53 tables, 500 figures; DM 168.00 ISBN 3-8047-1597-4 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 202-202 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200304
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  • 7
    Digitale Medien
    Digitale Medien
    Flow cytometric monitoring of Rhodococcus erythropolis and Ochrobactrum anthropi in a mixed culture (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 219-233 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The GRAM-positive bacterium Rhodococcus erythropolis K2-3 and the GRAM-negative Ochrobactrum anthropi K2-14 are capable of synergistically degrading 4-(2,4-dichlorophenoxy)butyric acid (2,4-DB). The two strais execute this task in a symbiotic manner, but the nature of the interaction involved in the degradation is only partially understood as yet. An essential first step in elucidating the interaction is to be able to monitor the two strans separately, at the cellular level, within mixed populations. Therefore a method exploiting fluorescently labelled lectin probes was developed. Since Concanavalin A (Con A) binds specifically to R. erythropolis K2-3, it was selected and linked to the fluoresent dye Bodipy 630/650, which has an excitation maximum in the red part of the visible light spectrum. Forward light scatter (FSC) and DNA fluorescence from both strains were also measured to obtain simultaneous information about their physiological states. The three parameters were conveniently monitored by dual and triple excitation flow cytometry in conjunction with double fluorescent staining techniques. In addition, the strains were identified using an epifluorescence microscope. These techniques were found powerful tools for the population analysis of this mixed bacterial system.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200306
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  • 8
    Digitale Medien
    Digitale Medien
    Scientific methodology for complex systems: Macroscopic patterns in eco- and anthropo-sphere (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 235-274 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: A quite unconventional, innovative scientific methodology called “macroscopic pattern analysis” is presented in this paper. This approach is more adequate in the case of complex systems than the well-known microscopic, mechanistic approach. Complex systems are not only attracting more engineering interest, but their scientific treatment is increasingly wanted by society due to the manifold problems in Earth's ecosphere. The macroscopic pattern approach will be explained in depth and illustrated in some case studies from the ecosphere (sustainability, hurricanes and avalanches), where nature serves as a teacher for the solution of the sustainability problem. Then, a series of case studies on macropatterns are described showing the problem-solving capacity for anthropo- and technosphere: sustainability in society with an index of sustainability, the eco-social market economy with eco-tech as an instrument, biokinetics, bioreactor mixing and integrated bioprocessing with models, design of cars and houses and even quality of life as an attempt to quantify macropatterns.The innovations are briefly compared in their problem-solving capacity with known approaches such as the microscopic method in science, technology and society (free market economy), including the evaluation of other indices and cleaner production, industrial ecology and zero emission initiative. Finally, a deeper integration of sciences, ethics, arts and nature will be introduced based on the vision with macroscopic pattern analysis, where the different domains of human life are integratable to effect a reconciliation.
    Zusätzliches Material: 22 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200308
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  • 9
    Digitale Medien
    Digitale Medien
    Biomining: Theory, microbes and industrial processes. Berlin, Heidelberg, New York, London, Paris, Tokyo, Hong Kong: Springer-Verlag XII + 302 pages, 80 figures, 27 tables; DM 184.00 ISBN 3-540-63252-2 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 30-30 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200105
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  • 10
    Digitale Medien
    Digitale Medien
    Dynamic responses of biofilters to changes in the operating conditions in the process of removing toluene and xylene from air (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 17-29 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The dynamic behaviour of biofilters intended to remove toluene and xylene from air was studied during transient states. Laboratory scale biofilters were filled with a mixture of peat, bark and wood and inoculated with a mixed microbial population. Toluene and xylene were applied both as single pollutants and as mixtures. Attention was focused on the evaluation of the following transients: the response of biofilters to step changes and peaks in pollutant concentrations, the effect of changes between single and multiple pollutant loadings and the response to shutdown periods.The biofilters demonstrated a good dynamic stability during transient states induced by change in inlet pollutant concentrations. Their time periods did not exceed three hours. No interaction between xylene and toluene degradation was observed during changes in loading with single pollutants or their mixture. The performance interruptions lasting less than 24 hours were found to have no significant influence on the removal efficiency of biofilters. When the biofilters were reacclimated after longer starvation periods, a short temporary decrease in efficiency whose minimum and duration were proportional to the length of a preceding shutdown period was observed. The longest starvation period (7 days) resulted in a reacclimation lasting 7 hours only. Adaptations of a microbial population to new operating conditions as well as sorption/desorption processes were suggested as the main factors influencing the dynamic reponse characteristics.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200104
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  • 11
    Digitale Medien
    Digitale Medien
    In vivo decolourization of the polymeric dye poly R-478 by corncob cultures of Phanerochaete chrysosporium (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 31-38 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: In this paper, the in vivo decolourization of the polymeric dye Poly R-478 by semi-solid-state cultures of Phanerochaete chrysosporium BKM-F-1767 (ATCC 24725) was investigated, employing corncob as a support. In order to stimulate the ligninolytic system of the fungus, the cultures were supplemented with veratryl alcohol (2 mM) or manganese (IV) oxide (1 g/l).Maximum manganese-dependent peroxidase (MnP) and lignin peroxidase (LiP) activities of around 2,000 U/l and 400 U/l were attained by the former, whereas the activities reached by the latter were of about 1,500 U/l and 200 U/l, respectively. Furthermore, laccase activity (around 150 U/l) was only detected in manganese (IV) oxide supplemented cultures.The polymeric dye Poly R-478 (0.02 w/v) was added to three-day-old cultures. A percentage of biological decolourization of about 85% was achieved using cultures supplemented with veratryl alcohol, whereas MnO2 cultures showed a rather lower percentage of around 58% after nine days of dye incubation. Moreover, a correlation between MnP activity and Poly R-478 decolourization could be observed, indicating that this enzyme is mainly responsible for dye degradation.In the present work, the in vivo decolourizing capability of the ligninolytic complex secreted by P. chrysosporium was investigated under the above-mentioned cultivation conditions, employing a model compound, such as the polymeric dye Poly R-478.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200106
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  • 12
    Digitale Medien
    Digitale Medien
    Editorial (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 187-187 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200302
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  • 13
    Digitale Medien
    Digitale Medien
    Reduction of halogenated derivatives of benzoic acid to the corresponding alcohols by Desulfovibrio vulgaris PY1 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 189-201 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Desulfovibrio vulgaris strain PY1 was isolated from a 3-chlorobenzoic acid (3CBA) degrading anaerobic enrichment culture, using anaerobic Percoll density centrifugation. When grown on pyruvate (20 mM), in the absence of sulphate and under strict anaerobic conditions, this organism converted not only the co-substrates benzoate (BA), 3-amino-BA and 3CBA to the corresponding alcohols but also ten other different halogenated benzoic acids, viz., 4-Cl-, 3-Br-, 4-Br-, 3-I-, 3-F-, 4-F-, 2,4-di-Cl-, 2,5-di-Cl-, 3,4-di-Cl- and 3,5-di-Cl-BA. This was verfied with HPLC and GC/MS spectrometric analyses. The yields of the co-substrate converted after 30 days of growth were between 20% and 88%, depending on the compounds which had been added at initial concentrations of 500 μM. Sulphate, sulphite, thiosulphate and disulphite inhibited the formation of 3-Cl-benzyl alcohol (3CBOH), i.e. a 97 to 99% inhibition, and nitrate and sulphur had no effect (a 7-10% inhibition). In cell-free extracts, the reduction of 3CBA to 3CBOH required strict anaerobic conditions, pyruvate or H2 as electron donors and the addition of methylviologen (MV), FAD, FMN or ferredoxin as electron carriers. The specific activity of the reduction of 3CBA to 3CBOH in crude extract was 5.3 nmol/(mg protein min). The reaction was not inhibited by additions of sulphate or sulphite (5 mM), but was completely inhibited at concentrations of 10 mM 3CBA or 50 mM BA. A carboxylic acid reductase (aldehyde dehydrogenase), which acted on non-activated 3CBA and was responsible for the reduction of 3CBA to 3-Cl-benzaldehyde, was found in the solube fraction (94% of the total activity). These results demonstrate that strain PY1 was able to effectively reduce a wide range of halogenated benzoic acids to the corresponding alcohols.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200303
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  • 14
    Digitale Medien
    Digitale Medien
    Socio-ecological strategies for future sustainability a review of an internet conference (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 203-218 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The recent upsurge in information technology has provided the international community with an easy access to professional journals (e.g. Electronic Journal of Biotechnology at http://www.ejb.org; etc.), discussion groups (e.g. bioenergy@cret.org; digestion@crest.org; etc.) and recently to electronic international conferences (e.g. ICIBS; http://www.cid.harvard.edu/cidbiotech, etc.) as well as a series of biotechnological information material (e.g. http://www.psrast.org, etc.) to stay in contact and receive up-to-date information in biotechnology. There is no doubt that this new technology will be more cost effective in future and reach more people in communities around the globe.This review reports on one such an electronic conference aiming at bridging the communication gap between developed and developing countries. This conference dealt with integrated biosystems and has provided an excellent forum for more than 100 active participants from all regions of the world. As has been demonstrated in this review, the conference was able to show the very different approaches towards the use of biotechnology in developed and developing countries, cold and tropical climate regions owing to their different ecological, economical and societal problems. It also demonstrated very clearly that the field of molecular genetics and/or genetic engineering is not a priority issue in developing countries, but rather the need for clean technologies, multiproduct formation through socio-economic integrated biosystems, e.g. incorporating microbial waste management into agro-industries, in human activities and their roles in creating better health conditions, a better environment and sustain development.It is hoped that this review will lead to a greater use of the electronic facilities available to inform and educate both the northern and the southern communities more readily of their needs and requirements to improve understanding and efforts for a sustainable future.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200305
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  • 15
    Digitale Medien
    Digitale Medien
    Application of zeolites in the downstream processing of the character impact compound 2,5-dimethyl-4-hydroxy-furan-3-one (furaneol) (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 275-288 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The purpose and scope of this article is to introduce capable zeolites into downstream processing of natural compounds, especially flavour compounds like 2,5-dimethyl-4-hydroxy-3(2H)-furan-3-one (Furaneol®Furaeol is a registered trademark of FIRMENICH, Ch). The synthesis and the recovery of Furaneol from L-rhamnose are presented. Therefore adsorption isotherms of the zeolites ZSM5 and DAY with varying modules have been determined and adsorption experiments using model and reaction mixtures of Furaneol synthesis were performed and will be discussed.
    Zusätzliches Material: 11 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200309
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  • 16
    Digitale Medien
    Digitale Medien
    Formation of aminium lactates in lactic acid fermentation. Fermentative production of 1,4-piperazinium-(L,L)-dilactate and its use as a starting material for the synthesis of dilactide (Part 2) (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 289-304 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: A fermentation process for manufacturing 1,4-piperazinium-(L,L)-dilactate from renewable raw materials and a method for processing this product into L,L-dilactide are described. Lactic acid fermentation with Lactobacillus paracasei was modified in such a way that pH control occurred by using an aqueous solution of piperazine as a correcting agent instead of sodium hydroxide solution. The production of a stoichiometrically composed piperazinium lactate was possible when the pH was 5.0. From 5.0 kg of glucose and 2.15 kg of piperazine, 6.65 kg of 1,4-piperazinium-(L,L)-dilactate were formed in the fermentation process. Separation from fermentation broth, purification and concentration of the product in aqueous solutions were carried out by means of ultrafiltration, nanofiltration and electrodialysis. Total product retention by the membranes used was about 33%. The crystalline salt was obtained by vacuum evaporation. Processing of the 1,4-piperazinium-(L,L)-dilactate into L,L-dilactide was performed in a special glass reactor. A product yield of 70% was achieved. The purified product was characterized by elementary analysis, as well as solubility behaviour, polarity and spectroscopic data. An overall process consisting of the stages fermentation, purification and concentration of piperazinium dilactate as well as cyclization of the latter to dilactide is described.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200310
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  • 17
    Digitale Medien
    Digitale Medien
    Sanitization of immobilized biocatalysts for the production of 6-aminopenicillanic acid (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 161-168 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Five different chemical reagents and γ-rays were tested for the sanitization of immobilized biocatalysts with high penicillin G acylase (PGA) activity. The most effective chemical reagents were N-cetyl-N,N,N-trimethylammonium bromide (CTAB) and 2-isopropyl-5-methylphenol (thymol). The optimum concentration of CTAB for the treatment of the immobilized enzyme was 0.25% [w/v] and 1 h, for immobilized cells 0. [w/v] and 3 h. The optimum concentration of thymol for the immobilized enzyme was found to be 0.1% [w/v] and 1 h, for immobilized cells 0.27% [w/v] and 2 h. The optimum dose of γ-rays for the sanitization of the immobilized enzyme was established as 3.2 kGy, for immobilized cells as 4.5 kGy.
    Zusätzliches Material: 5 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200211
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  • 18
    Digitale Medien
    Digitale Medien
    Chemical sensors and biosensors for medical and biological applications. Chichester, New York, Weinheim, Brisbane, Singapore, Toronto: John Wiley & Sons XII + 413 pages, 82 figures, 41 tables; DM 198.00, ISBN 3-527-28855-4 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 234-234 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200307
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  • 19
    Digitale Medien
    Digitale Medien
    Advanced primary treatment of waste water using a bio-flocculation-adsorption sedimentation process (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 53-64 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: An advanced primary treatment process for a municipal waste water was systematically studied, using a bio-flocculation-adsorption, sedimentation and stabilzation process (BSS). It was shown that the organic removal efficiency was higher than that of the traditional primary treatment processes but lower than that of the traditional secondary treatment processes. Both adsorption and bio-flocculation played an important role in the removal of pollutants. The activated sludge within the bio-flocculation-adsorption tank could be considered a bio-flocculent which improved the quality of the effluent from the primary treatment process. As the effluent of the BSS process did not meet the requirements for a typical secondary effluent, the process may be regarded as an advanced (or enhanced) primary treatment process, suitable for waste water containing a high concentration of suspended solids and colloidal particles.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200109
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  • 20
    Digitale Medien
    Digitale Medien
    Airborne bacteria and fungal spores in the indoor environment. A case study in Singapore (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 67-73 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The concentration of airborne fungal spores and bacteria as related to room temperature, humidity and occupancy levels within a library building in Singapore was determined. Measurement of indoor air quality with respect to microorganisms is of particular importance in tropical environments due to the extensive use of air-conditioning systems and the potential implications for human health. This study has revealed a number of interesting relationships between the concentrations of fungal spores and bacteria in relation to both environmental and human factors. The levels of fungal spores measured in the indoor environment were approximately fifty times lower than those measured outside, probably because of the lowered humidity caused by air-conditioning in the indoor environment. The variation in fungal spore concentration in the outdoor environment is likely to be due to the diurnal periodicity of spore release and the response to environmental factors such as light temperature and humidity. The indoor concentration of fungal spores in air was not clearly correlated to concentrations measured in air outside of the library building and remained relatively constant, unaffected by the difference in the numbers of occupants in the library. In contrast, the indoor concentrations of bacteria in air were approximately ten times higher than those measured outdoors, indicating a signficant internal source of bacteria. The elevated levels of indoor bacteria were primarily attributed to the number of library occupants. Increased human shedding of skin cells, ejection of microorganisms and particulates from the respiratory tract, and the transport of bacteria on suspended dust particles from floor surfaces probably accounts for the strong positive correlation between occupancy levels and the concentration of bacteria in internal air.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200111
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  • 21
    Digitale Medien
    Digitale Medien
    Masthead (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000) 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200201
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  • 22
    Digitale Medien
    Digitale Medien
    Conference Announcement. 11. Weltkongress biotechnology 2000 in Berlin: The molecular key for biotechnology (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 96-96 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200203
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  • 23
    Digitale Medien
    Digitale Medien
    Innovative use of Thiobacillus ferrooxidans for the biological machining of metals (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 87-96 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Preliminary results on the novel use of the bacterium Thiobacillus ferrooxidans (ATCCJ 3598 and ATCC33020) for the micro-machining (or biomachinig) of metals are reported. Biomachning is a controlled microbiological process to selectively form microstrucutures on a metal work-piece by metal removal (or dissolution) using microorganisms. Applying copper and mild steel as work-pieces, it was shown that the mass removed increased proportionately with machining time. In another experiment, the work-pieces were coated with organic photo-resistive materials to mask (i.e. protect) certain regions of the metlas, thereby defining the microstructure to be formed. The unmasked regions were successfully biomachined; the final machined profile was shown to be similar to the coating image on the original metal. Although biomachining proceeded at a slower rate than chemical machining, the undesired leaching of the metal in the region under the masked area (termed undercutting) was not as severely encountered when compared with the latter. This work demonstrates the potential use of microorganisms for the biomachining of metals. As a “green process”, the innovative use of T. ferrooxidans for the micro-machining of metals opens up the possibility of biomachining as an alternative to conventional metal processing.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200202
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  • 24
    Digitale Medien
    Digitale Medien
    Improvement of the bioavailability of hydrocarbons by applying nonionic surfactants during the microbial remediation of a sandy soil (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 99-118 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: During the microbial treatment of a sandy model soil artificially contaminated with polycyclic aromatic hydrocarbons (PAHs), a large residual pollution was found. The remainig PAHs were sorbed into the micropores of the soil and were therefore not bioavailable. Using a lab-scale precolator, the microbially pretreated soil was subjected to aftertreatment with surfactants with the aim of further degradation of its pollution. Two commercial nonionic surfatants of the polyethoxylate type, Präwozell F1214/5 N and Sapogenat T-300, were used. The surfactants differ both in their physicochemical properties (CMC value, PAH solubilization capacity, adsorption onto soil) and in their microbial degradability. During aftertreatment under permanently aerobic conditions, only a weak PAH accumulation in the liquid phase was observed, which was due to a low solubilization rate as well as to simultaneous microbial degradation of the dissolved PAHs. Temporary anaerobiosis successfully suppressed the microbial degradation of both the surfactant and the solubilized PAHs, resulting in a more intensive PAH accumulation. But the PAH content of the soil - the essential criterion for evaluating the efficiency of surfactant application - was not decreased to a larger extent with surfactants than without them. To find out why the surfactants failed to act, the surfactant and hydrocarbon distribution among the liquid and solid phases was studied in mixtures of phenantherne-spiked solis and Präwozell-containig liquids; at heavy phenanthrene loading, the aqueous phase was saturated with PAH; at weak loading, it was unsaturated. Model-aided data analysis showed that the soil may contain PAH in two fractions: strongly sorbed into soil pores and, in the case of heavy loading, also weakly attached to the soil surface. The latter is easily extractable, resulting in a PAH-saturated liquid, while strongly adsorbed PAH is only partially dissolved due to competition between the micelles and the soil pores for the PAH. The microbially pretreated soil contains only strongly bound PAHs, which are as difficult to extract by surfactants as they are poorly accessible for microbes.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200205
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  • 25
    Digitale Medien
    Digitale Medien
    Influence of crude oil contamination on the bacterial community of semiarid soils of Patagonia (Argentina) (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 129-146 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Autochthonous bacteriocenoses in semiarid soils in Patagonia were found to be capable of rapidly adapting to high contamination with crude oil. This adaptation at community level is due to the selective enrichment of hydrocarbon-utilizing bacteria always present in these soils. Immediately after a heavy contamination with crude oil, the authochthonous bacteriocenosis contained about 28% hydrocarbon-utilizing bacteria which could be classified into eight ecotypes with characteristic metabolic profiles. Mainly n-alkanes were used as growth substrates of representative strains. After seven months' exposure to crude oil, the bacteriocenosis consisted almost entirely of hydrocarbon-utilizing bacteria. At least fourteen ecotypes were distinguishable, and the majority of representative strains were able to metabolize a broad spectrum of aliphatic and aromatic hydrocarbons. Corresponding to the significant alteration of the physiological diversity, drastic changes to the taxonomic diversity were also found. Whereas at the beginning of the study the autochthonous bacteriocenoses were dominated by GRAM-positive genera of the Actinomycetales (Dietzia, Gordona, Nocardia, Rhodococcus, Streptomyces) with high ecological potency, after just two months' exposure to crude oil, GRAM- negative bacteria (especially Pseudomonas stutzeri) became predominant within the hydrocarbon-utilizing bacteriocenoses accompanied by some GRAM-positive genera of the Actinomycetales with a significantly lower abundance. These findings underline the importance of Pseudomonas and some genera of Actinomycetales for processes of natural attenuation and the technically supported in situ bioremediation of soil polluted by crude oil in Patagonia.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200207
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  • 26
    Digitale Medien
    Digitale Medien
    Optimization of some parameters of solid state fermentation of wheat bran for protease production by a local strain of Rhizopus oryzae (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 149-159 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Some parameters of the production of an alkaline protease by Rhizopus oryzae in the solid state fermentation of wheat bran were optimized. Using the optimum parameters of an inoculum age of 7 days, an incubation time of 9 days, an amount of CZAPEK-DOX (liquid medium) of 6 ml/g bran and an incubation temperature of 33°C, an activity of 50 U/g bran was achieved. The initial pH of the CZAPEK-DOX medium had little effect. Re-incubation of mouldy bran with only fresh CZAPEK-DOX yielded 3 times total activity compared to single-cycle fermentation. As for the effect of the amount CZAPEK-DOX medium, the water constituent contributed more to activity increase than did the salt component. The ARRHENIUS activation energies were 23 and 7.9 kcal/mole below and above the optimum of 33°C, respectively. In all the studies, along with protease production, variation of protein content and specific activity were also observed. Attempts were made to explain the effects and also gauge their implications for large-scale production.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200209
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  • 27
    Digitale Medien
    Digitale Medien
    Molecular genetics of plant development. Cambridge, New York, Melbourne: Cambridge University, 365 pages, 165 figures, 2 tables; $ 39.95 (paperback) ISBN 0-521-58784-0 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 184-184 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200214
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  • 28
    Digitale Medien
    Digitale Medien
    Masthead (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000) 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200301
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  • 29
    Digitale Medien
    Digitale Medien
    Investigation into the biotechnological modification of wood and its application in the wood-based material industry (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 305-312 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Because of the growing utilization of renewable raw materials, the technical use of lignocellulosic fibres from wood and other annual plant materials is becoming increasingly important. The conventional production process of fibreboards is characterized by high-energy consumption and use of ecologically insecure synthetic lesins. Approximately 40 to 45% of the total energy expenditure are used for the thermo-mechanical pulping. Because of high plastication temperatures, an inactive lignin crust on the fibre surface is formed. For that reason, for glueing of the fibres, urea formaldehyde and melamin resins are usually used. The costs for the resin amount to approximately 50% of the entire material costs. In addition, environmental problems are caused. The aim of our investigation is the reduction of energy and resin consumption by enzymatic modification of wood chips and the enzymatic activation of the inherent bonding strength of the material. The first industrial use of fungi for the modification of wood was in the production of “Myco wood”. Pleurothus ostreatus and Trametes versicolor were applied for nonsterile delignification of beech wood. The present investigation of the authors deals with the mycological pre-treatment of wood chips in order to reduce the energy consumption during wood pulping. The screening results favour the brown rotter Gleophyllum trabeum for pinewood (Pinus silvestris) and the white rotter Trametes hirsuta for beech (Fagus silvatica). Both species show resistance against mould fungi. The use of submerged inoculum of these fungi has the advantage over wheat inoculum that the lag phase is less than 12 hours and that the addition of nutrients or fungicides is not necessary. Short-time wood chip incubation results in a 40% decrease of energy consumption during thermo-mechanical pulping and in improved fibreboard properties. Lignin reduction could not be determined by gravimetrical and x-ray microanalysis.Comparative investigations of fibre incubation using laccase, a submerged culture of Trametes versicolor and rape straw fibres show a high increase in bending and tensile strength and an improvement in the hygroscopic properties of glue-free fibre boards for the last two incubation kinds. Similar effects have been obtained incubating pine wood fibres for the production of fibre sheets with enzyme medium of Trichoderma reseei.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200311
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  • 30
    Digitale Medien
    Digitale Medien
    Biotechnological applications in the oil industry (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 335-350 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: During the 20th century, important relationships developed between the oil industry and both microbiological and biotechnological research. Basic microbiological research has played an important role in both the exploration and production sectors of the oil industry, but as the maturity of the industry has progressed, such contributions have been relegated with respect to their importance. With respect to refining and petrochemicals manufacture, process routes have been extensively researched, but only rarely have the biotechnological solutions developed satisfied the economic criteria that resulted in major investment. In fact, situations exist where investment has occurred, but project life was unrealistically short, suggesting a need for extreme caution when evaluating biotechnological processes for the oil industry. However, as far as engineered processes for both biotreatment and bioremediation are concerned, the fundamental research that has underpinned other areas of hydrocarbon microbiology will finally prove to be of both technical and economic value, in ensuring that the essential needs of treatment, rather than disposal, and restoration, rather than environmental destruction, can be satisfied by the oil and other industries involved in both geochemical manipulation and natural resource exploitation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200314
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  • 31
    Digitale Medien
    Digitale Medien
    The influence of growth rate and growth-limiting factors on the production of ice nuclei in Pseudomonas syringae CCM 4073 in continuous culture (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 369-372 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The influence of different growth-limiting factors - namely the sources of carbon, nitrogen and phosphorus and the dilution (growth) rate - on the ice-nucleation activity of Pseudomonas syringe CCM 4073 was studied. A higher ice-nucleation activity was observed at a lower dilution (growth) rate (D = 0.1 h-1) than at a higher dilution (growth) rate (D = 0.3 h-1). Remarkable differences in ice-nucleation activity were found in its dependence on the growth-limiting factor. The highest ice-nucleation activity was observed under carbon limitation (T90 = -2.7°C), a medium activity under nitrogen limitation (T90 = -5°C) and lowest activity under phosphorus limitation (T90 = -12.3°C). After the addition of excess nitrogen or phosphorus to steady-state cultures, the ice-nucleation activity was restored.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200316
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  • 32
    Digitale Medien
    Digitale Medien
    Imaging living cells. Berlin, Heidelberg, New York, London, Paris, Tokyo, Hong Kong: Springer-Verlag, 1999 XXI + 394 pages, 97 figures, 39 tables; DM 179.00 ISBN 3-540-65051-2 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 39-40 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200107
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  • 33
    Digitale Medien
    Digitale Medien
    Manual of industrial microbiology and biotechnology. Washington, D. C.: ASM Press, 1999 830 pages; £ 59.00 ISBN 1-55581-128-0 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 65-65 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200110
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  • 34
    Digitale Medien
    Digitale Medien
    Laborhandbuch für die Untersuchung von Wasser, Abwasser und Boden. Weinheim, New York, Chichester, Brisbane, Singapore, Toronto: Wiley-VCH Verlag GmbH, XII + 232 pages, 43 figures, 46 tables; DM 78.00 ISBN 3-527-28888-0 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 74-74 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200112
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  • 35
    Digitale Medien
    Digitale Medien
    Use of various coffee industry residues for the cultivation of Pleurotus ostreatus in solid state fermentation (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 41-52 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Studies were carried out to evaluate the feasibility of using coffee industry residues, viz. coffee husk, coffee leaves and spent coffee ground as substrates in solid state fermentation (SSF) to cultivate edible mushrooms Pleurotus. Eight strains of Pleurotus ostreatus and two strains of Pleurotus sajor-caju were screened on a medium prepared from aqueous extract of coffee husk and agar. Based on best mycelial growth (9.68 mm/day) and biomass production (43.4 mg/plate in 9 days at 24°C), the strain P. ostreatus LPB 09 was selected for detailed studies. SSF was carried out using these substrates under different moisture conditions (45-75%) and spawn rates (2.5-25%). In general, although a 25% spawn rate appeared superior, the 10% spawn rate was recommended for all the three substrates in view of the process economics, as there was not any significant difference in the increase with 10 to 15%. The ideal moisture content for mycelial growth was 60-65% for coffee husk and spent coffee ground, and 60-70% for coffee leaves. The biological efficiency (BE), which is defined as the ratio of the weight of fresh fruiting bodies to the weight of dry substrate, multiplied by 100, and which indicates the fructification ability of the fungus for utilizing the substrate, was best with coffee husk. With coffee husk as the substrate, the first fructification occurred after 20 days of inoculation, and the biological efficiency reached about 97% after 60 days. When coffee leaves were used as the substrate, no fructification was observed even upon prolonged cultivation. With spent ground as the substrate, the first fructification occurred 23 days after inoculation and the biological efficiency reached about 90% in 50 days. There was a significant decrease in the caffeine and tannin contents (61 and 79%, respectively) of coffee husk after 60 days. It was remarkable to observe that caffeine was adsorbed onto the fruiting body (0.157%), indicating that it was not completely degraded by the fungal culture. However, no tannins were found in the fruiting body, indicating that the fungal strain was capable of degrading them. The results showed the feasibility of using coffee husk and spent coffee ground as substrates without any pre-treatment for the cultivation of edible fungi in SSF, and provided one of the first steps towards an economical utilization of these otherwise unutilized or poorly utilized residues.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200108
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  • 36
    Digitale Medien
    Digitale Medien
    A model for biopigment formation by Serratia marcescens biovar A2/6 in batch cultures containing lactic acid and beef extract (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 75-81 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Serratia marcescens biovar A2/A6 is able to produce a red pigment as a secondary metabolite which has antimicrobial activity. This paper describes its growth and biopigment formation in batch cultures, in media containing different concentrations of lactic acid and beef extract as carbon and nitrogen sources, respectively. An unstructured model has also been developed to describe its growth, lactic acid uptake and biopigment formation. The comparison of simulated and experimental data shows that the proposed model predicts reasonably well the system behaviour over a range of conditions.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200113
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  • 37
    Digitale Medien
    Digitale Medien
    Mutation breeding. Theory and Practical Applications. Cambridge: Cambridge University Press 353 pages, 18 figures, 5 tables; $ 120.00 ISBN 0-85404-750-6 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 97-98 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200204
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  • 38
    Digitale Medien
    Digitale Medien
    Masthead (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000) 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200101
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  • 39
    Digitale Medien
    Digitale Medien
    Press Release (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 334-334 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200313
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  • 40
    Digitale Medien
    Digitale Medien
    The impact of hydrocarbon remediation (diesel oil and polycyclic aromatic hydrocarbons) on enzyme activities and microbial properties of soil (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 313-333 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The impact of hydrocarbon remediation on several enzyme activities (catalase, dehydrogenase, lipase, protease, urease, alkaline phosphomonoesterase, fluorescein diacetate hydrolysis) and microbial properties (biomass-C, respiration, N-mineralization, qCO2, microbial counts) was evaluated in a laboratory study over a period of 10 weeks. A pristine soil was contaminated with diesel oil (10 mg/g soil) or with a mixture of phenanthrene and naphthalene (total amount 1 mg/g soil) and supplemented with inorganic nutrients to give a C:N ratio of 20:1. The corresponding controls consisted of uncontaminated nutrient-supplemented soil. Oil contamination caused a significant initial increase of all biological parameters measured. In the presence of PAHs, biomass-C, respiration, protease activity and heterotrophic counts were significantly enhanced, while urease activity was depressed. N-mineralization was initially, however, reversibly inhibited in the presence of oil and PAHs.The measured parameters behaved differently over time: Biomass-C, respiration and alkaline phosphomonoesterase activity reached a maximum activity after about 2-5 weeks, corresponding to the period during which the majority of hydrocarbons disappeared, and declined thereafter to the background level. Activities of catalase and dehydrogenase also followed this pattern, however, were characterized by fluctuations. Activities of lipase, protease, urease and fluorescein diacetate hydrolysis increased and remained almost constant throughout the incubation period.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200312
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  • 41
    Digitale Medien
    Digitale Medien
    Action as a dynamic property of the genotype × environment interation implications for biotechnology (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 351-368 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The action resonance theory (ART), a hypothesis based on a logical extension of EINSTEIN's theory of Brownian movement, suggests that the genotype × environment interaction can be modelled as forceful encounters of the gene-products of an organism with its environment. This model has implications for molecular and cell biology, morphogenesis, evolutionary development via mutation, the mechanism of natural selection and overall function of ecosystems, extending SCHRÖDINGER's programme for molecular biology. Action, a thermodynamic property with the same physical dimensions as angular momentum and PLANCK's quantum of action, is proposed to be reversibly generated as a result of the molecular exchange of quanta, which become resonant at equilibrium, corresponding to an optimum degree of entropy and action for living systems. Because the theory can potentially predict solutions to unsolved problems such as the folding of proteins it has strong implications for successful genetic modification of organisms and for biotechnology in general; the design of a programme of research to test this theory is proposed. A key element in this research programme, improving productivity and sustainability, would be the need to select genetically modified strains in the ecological environment or niche in which they are required to function.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200315
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  • 42
    Digitale Medien
    Digitale Medien
    Encyclopedia of molecular biology. (Four-volume set; first edition). New York, Chichester, Weinheim, Brisbane, Singapore, Toronto: John Wiley & Sons, Inc., 1999, 2878 pages with over 2,000 entries and 900 figures; £ 925.00, ISBN 0-471-15302-8 (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 16-16 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200103
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  • 43
    Digitale Medien
    Digitale Medien
    Continuous preparative liquid chromatography in the downstrem processing of biotechnological productsUpdate lecture from the 17 Annual Meeting of Biotechnologists (organized by the DECHEMA e. v.), Wiesbaden, 27-29 April 1999. (2000)
    Berlin : Wiley-Blackwell
    Acta Biotechnologica 20 (2000), S. 3-15 
    Details
    ISSN: 0138-4988
    Schlagwort(e): Life Sciences ; Life Sciences (general)
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Continuous counter-current chromatographic processes have been successfully used in the petrochemical and sugar industry over the last 30 years. Only recently has simulated moving bed (SMB)-technology attracted widespread interest in the pharmaceutical industry, mainly as a very efficient system for chromatographic enantioseparation. The application of this technique to the downstream processing of biotechnological products requires some specific changes to meet the special demands of bioproduct isolation. Production processes are set up on an multi-ton scale, for example, for the purification of fructose with both yield and purity higher than 90%. Examples for other mono- and oligosaccharides are reported. In the purification of fatty acids or fat soluble vitamins, SMB technology under supercritical fluid conditions gives additional benefits and increases the productivity by a factor of four when a pressure gradient is applied. Another field of operation is the isolation of drug compounds from natural sources where different batch- and SMB-chromatographic steps could be successfully combined. First examples are reported for cyclosporine A and paclitaxel isolation. Finally, step-gradient elution modes can be used continuously, as demonstrated for the isolation of monoclonal antibodies.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/abio.370200102
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  • 44
    Digitale Medien
    Digitale Medien
    Masthead (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989) 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720101
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  • 45
    Digitale Medien
    Digitale Medien
    The Conformation of Cycloartenol Investigated by NMR and Molecular Mechanics (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 1-13 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Cycloartenol (4), a natural plant sterol, was shown to be an effective membrane reinforcer; this was attributed to its conformation. We now present a conformational analysis of 4 by molecular modeling and NMR. Molecular modeling suggests that two conformations I and II coexist, differing mainly at the level of ring C, and of nearly equal energy, I and II each having ring A and B in a chair and half-chair conformation, respectively, with ring C 1,3-diplanar in I (solid-state structure as determined by X-ray crystallography) and in chair conformation in II. A complete assignment of the 1H- and 13C-NMR spectra of 4 and the entire coupling network in rings A and B is determined by various modern NMR techniques. The conformation of rings A and B thus determined is in agreement with conformations I and II. Low-temperature NMR experiments show a fast equilibrium between two conformations, presumably I and II. It is concluded, therefore, that the cyclopropane ring of 4 produces a flexibility at the level of ring C which may be important for the membrane properties.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720102
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  • 46
    Digitale Medien
    Digitale Medien
    Palladium(0)-Catalyzed Cyclizations of Simple 1-Aryl-1,7-octadien-3-yl Acetates. Preliminary communicationPresented (W.O.) at the ‘3e Congrès national de la Société Française de Chimie’, Nice, September 5, 1988. (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 14-16 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Dienyl acetates 2 lacking a geminal disulfone or a malonate group cyclize selectively to (E)-l-methylidene-2-styrylcyclopentanes 4 in the presence of 7 mol-% of [Pd(PPh3)4].
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720103
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  • 47
    Digitale Medien
    Digitale Medien
    Über den Einfluss des Akzeptor-Teilchromophors bei Dimethin-merocyanin-Farbstoffen auf das Aggregationsverhalten in wässriger Lösung (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 17-28 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: On the Influence of the Acceptor Part of the Chromophor of Dimethinemerocyanine Dyes upon the Aggregation Tendency in Aqueous SolutionA series of novel long-chain alkyl-dimethinemerocyanine dyes containing sulfonate groups is synthesized in good yield and their aggregation tendency in H2O and in organic solvent/H2O mixtures investigated. The merocyanine dyes 11 and 15 only exhibit an intense, red-shifted absorption band due to J-aggregation in H2O without addition of salt. The influence of cationic and anionic tensides and other compounds as urea, glucose, and polysaccharides upon the J-aggregation tendency is investigated.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720104
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  • 48
    Digitale Medien
    Digitale Medien
    Generation and Trapping of TriafulveneFulvene, Fulvalenes, Part 55; Part 54: [1].Short communication: [2]. (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 29-40 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Substituted methylidenecyclopropanes 12a-d, being easily available from 1,1-dibromo-2-(phenylthio)-cyclopropane (9a), are attractive precursors of triafulvene (2-methylidene-1-cyclopropene; 1). Both the sulfoxide 12b and the sulfone 12c react with an excess of alkoxides (t-BuOK and NaOMe) to give 12e and 12f, respectively, while the sulfinyl group of 12b may be replaced by the PhCH2S substituent in the presence of PhCH2SH/t-BuOK. These reactions (Scheme 4) may be explained by assuming 1 as a reactive intermediate, although an alternative sequence including carbene 20 (Scheme 6) is not completely ruled out. D-labelling experiments (Scheme 5) do not give conclusive evidence due to D scrambling, but deprotonation/methylation sequences show that H—C(2) of 12a-c is the most acidic proton. Final evidence for 1 results from the reaction of 12d with cyclopentadienide (Scheme 7): the reaction of 1 with cyclopentadiene produces the expected [4 + 2]-cycloaddition product 23, while some mechanistic insight results from the sequence 12d → 24 → 25.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720105
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  • 49
    Digitale Medien
    Digitale Medien
    A Nonconcerted Intramolecular Diels-Alder Reaction of Chiral Allenic-Acid Derivatives (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 59-64 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The reaction between the chiral allenic acid (+)-(S)-1 and the carbodiimides 2a-d and the keten-imine 6 gives, under mild conditions, the tricyclic compounds 3-5, 7, and 8. Low diastereoselectivity and a partial loss of optical activity are observed. A stepwise mechanistic pathway via a biradical intermediate is postulated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720108
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  • 50
    Digitale Medien
    Digitale Medien
    Konkurrenz von Endoperoxid- und Hydroperoxid-Bildung bei der Umsetzung von Singulett-Sauerstoff mit cyclischen, konjugierten Dienen. Teil I (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 51-58 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Competition of Endoperoxide and Hydroperoxide Formation in the Reaction of Singlet Oxygen with Cyclic, Conjugated DienesRose-bengal-sensitized photooxygenation of (-)-(R)-α-phellandrene (1) in MeOH at room temperature yielded a complex mixture of products, contrary to previous reports describing cis-(3S, 6R)-epidioxy-p-menthene (2) and trans-(3R, 6S)-epidioxy-p-menthene (3) as the only products. The mixture was separated by prep. HPLC (silica gel, pentane/Et2O 9:1). Besides the known endoperoxides 2 (yield 39%) and 3 (26%), all those hydroper-oxides, which can be deduced from an ene reaction of 1O2 with 1, were isolated, i.e. 4β-p-mentha-2,5-dien-1β-yl hydroperoxide (4) (14%), 4β-p-mentha-2,5-dien-1α-yl hydroperoxide (5) (9%), (2R, 4R)-p-mentha-1(7), 5-dien-2-yl hydroperoxide (6) (2,1%), (2S, 4R)-p-mentha-1(7),5-dien-2-yl hydroperoxide (7) (1,5%) and (1R)-p-mentha-3,6-dien-yl hydroperoxide (8; 1,5%; Scheme 1). Furthermore, the constant cis/trans ratio for all diastereoisomeric pairs (2/2, 4/2, 6/2) was striking. With the help of the two possible conformers 1a and 1b of the starting material a model of a common first step for endoperoxide as well as for hydroperoxide formation is developed. A photooxygenation at -50° supports this model. The absolute value of the cis/trans ratio changes in the same way for the endoperoxides and the hydroperoxides.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720107
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  • 51
    Digitale Medien
    Digitale Medien
    Versuche zur Synthese von Calicen aus trisubstituierten Cyclopropanen und Cyclopentenon56. Mitt. über Fulvene, Fulvalene; 55. Mitt. [1]: Kurzmitt. (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 41-50 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Attempted Synthesis of Calicene from Trisubstitued Cyclopropanes and CyclopentenoneThe Li carbenoids 4, prepared by treatment of substituted 1,1-dihalocyclopropanes with BuLi, are reacted with cyclopent-2-enone under thermodynamic and kinetic control (Scheme 1). In general, the latter procedure gives better yields of cyclopropylcyclopentenols 5a-e, but the reaction seems to be controlled mainly by the steric and electronic properties of the substituent Y. So, with 4b and 4e, the main reaction is the attack of the carbenoid at C(1) of cyclopent-2-enone, while 4a (Y = PhS) predominantly deprotonates the ketone (Scheme 4). Whereas 5d and 5e can easily be converted to the dihydrocalicenes 6d and 6e (Scheme 6), the attempted elimination of H2O from 5a-c leads to the rearranged products 13-2 due to the opening of the cyclopropane ring (Scheme 5). Finally, the generation of the parent compound 2 from the silylated precursor 6d is attempted: treatment with MeO- gives the addition products 18A/18B, while the reaction with Br2 provides 19 by a bromination/dehydrobromination sequence (Scheme 7).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720106
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  • 52
    Digitale Medien
    Digitale Medien
    Locoselective [4 + 2] Cycloadditions of Vinylindoles with Inverse Electron Demand: A new access of indolyl-substituted and annellated pyridazinesDedicated to Prof. Dr. C. H. Brieskorn (Würzburg, FRG) on the occasion of his 75th birthday (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 65-72 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: 2-Vinylindole (1a) and its donor- and acceptor-substituted (E)-derivatives 1b-e react highly locoselectively with dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate (3) to form the novel (indol-2-yl)-1,4-dihydropyridazines 4a and 7 as well as the heterocyclic annellated pyridazines 4b, 5, and 6. The reactions of the structurally related 3-vinylindoles 2a-e with 3 also gave rise to new indol-3-ylpyridazines 8, 9, and 10. The locoselectivities of these Diels-Alder reactions were controlled mainly by steric effects.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720109
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  • 53
    Digitale Medien
    Digitale Medien
    Photochemistry of Thiophen-2(5H)-onesDedicated to Prof. Dr. O. E. Polansky on the occasion of his 70th birthday (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 83-92 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Mechanistic evidence for the light-induced ring opening of thiophen-2(5H)-ones 1 in alcohols affording α, β-unsaturated mercapto esters 2 is presented. Regio-and stereochemical aspects of the ring closure of alkenylthio (type 3) radicals 15 and 17 to S-heterocycles 16 and 18, of 3-thiahex-5-enyl radicals 4 to (tetrahydrothien-3-yl)methyl radicals 6 and of (2,3-dihydrothien-3-yl)methyl radicals 30 (type 7, but-3-enyl radicals) to cyclopropane-methyl radicals 29 are discussed. Irradiation (λ 350 nm) of 1 in cyclohexane in the presence of 2,3-dimethylbut-2-ene affords [2 + 2] cycloadducts 14 albeit in very low yields.
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720111
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  • 54
    Digitale Medien
    Digitale Medien
    Electronic and Molecular Structure of the C8H10+· Valence Isomers 1,3,5-Cyclooctatriene+· and Bicyclo[4.2.0]octa-2,4-diene+· from their Electronic absorption Spectra in Freon (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 73-82 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The molecular cations of 1,3,5-cyclooctatriene (COT+·) and bicyclo[4.2.0]octa-2,4-diene (BCO+·) can be observed intact in γ-irradiated Freon glasses, as opposed to Ar matrices where ionization is accompanied by extensive rearrangements. This proves the superiority of the Freon-glass method for the generation of metastable primary cations. The electronic absorption (EA) spectra reveal a) that a previous analysis of the BCO+· electronic structure on the basis of the ultraviolet photoelectron (UP( spectrum of BCO was incomplete, and b) that COT undergoes planarization upon ionization, in accord with qualitative expectations and MNDO calculations. A previously proposed LCBO model was used to assess the influence of the above geometry change on the electronic structure of COT+·.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720110
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  • 55
    Digitale Medien
    Digitale Medien
    Cyclization Studies with N-Mannich bases of 2-substituted indoles (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 93-100 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis of the indoles 7, 15, 16 with a 3-methoxyphenyl group, attached via an α-side chain of 1,2,or 3 CH2 units, is reported. These compounds, after appropriate protection at C(3), were transformed into the N-[(dimethylamino)methyl]indoles 22, 23, and 24, respectively. When treated with AcCl, these N-Mannich bases gave, in two cases, stable N-(chloromethyl)indoles 25 and 26. In the presence of SnCl4, ring closure occurred via electrophilic attack of 1-methylideneindolium ions on the methoxyphenyl group. Formation of seven-membered rings (→ 27, 28) and eight-membered rings (→ 29) was found to be a favorable process. Cyclization to six-membered rings did not occur within this series.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720112
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  • 56
    Digitale Medien
    Digitale Medien
    Template-Dependent Incorporation of Spin-Labeled Thymidine Analogs into Viral DNA (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 110-116 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis of novel pppUd analogs substituted at position C(5) with tethered nitroxide radicals is reported. It is shown that these analogs can serve as good substrates for E. coli DNA polymerase (Pol I) and T-4 DNA polymerase using lambda-phage DNA as template. The template-dependent incorporation of the substrates was established by radio-labeling and ESR experiments.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720114
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  • 57
    Digitale Medien
    Digitale Medien
    Stereoselektive Synthesen von Taxan-Derivaten (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 101-109 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Stereoselective Synthesis of Taxane DerivativesSubstituted racemic 4,8,12-trinortaxanes were prepared stereoselectively in several steps from the dienone 10. A variant of the de Mayo reaction with bicyclononenones 4 and cyclohexen produced the desired configuration at C(8) of the taxane framework. Retro-aldol cleavage of the tetracycle 5 led to the taxane skeleton 6. Stereoselective reduction followed by treatment with base afforded 7b. Hydrolysis of the acetal group and further reduction yielded 9 in which the relative configuration corresponds to the one of the natural products.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720113
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  • 58
    Digitale Medien
    Digitale Medien
    Asymmetric Diels-Alder reactions: X-Ray crystal-structure analysis of [N-((E)-But-2-enoyl)bornane-10,2-sultam]tetrachlorotitaniumPresented (WO) at the Annual Congress of the Royal Society of Chemistry, Canterbury, April, 1988. (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 123-130 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: An X-ray diffraction analysis of the crystalline complex 2b (MLn — TiCl4) shows a chelation of the carbonyl O-atom and the upper SO2 O-atom by TiCl4, a slightly pyramidal N-atom, and a π -face-stereoselective shielding of the C(α)-Si face by the CH2(3) group. The Ti-atom is in a pseudo-octahedral environment.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720116
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  • 59
    Digitale Medien
    Digitale Medien
    Metal Complexes with Macrocyclic Ligands. Part XXVIIPart XXVI. Cu2+-promoted hydrolysis of carboxylic- and phosphonic-acid esters in the side chain of tetraazamacrocycles (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 131-138 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The X-ray structures of the Cu2+ complexes of 1,4,8,11-tetraazacyclotetradecane derivatives with an ethylpro-pionate and diethylphosphonate group, 5 and 6, respectively, indicate that the metal ion is pentacoordinated by the four N-atoms of the macrocycle and one O-atom. In the case of 5, it is the carbonyl O-atom of the carboxylate group, whereas for 6 it is the phosphonyl O-atom of the phosphonate group. The hydrolysis kinetics of the functional group in the Cu2+ complexes with the 1,4,8,11-tetraazacyclotetradecanes 3-6 have been measured by pH-stat and stopped-flow techniques. The rate law for the hydrolysis of the carboxylates 3-5 is proportional to the complex concentration and to [OH-] up to pH 13, whereas that of the phosphonate 6 is proportional to [OH-] up to pH 11.5, becoming independent of [OH-] at pH 〉 11.5. The mechanisms of these two reactions are discussed, considering the possibility of an intra- or an intermolecular OH- attack and the results of the X-ray structure analyses.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720117
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  • 60
    Digitale Medien
    Digitale Medien
    A New Method for the Preparation of (E)-3-Acylprop-2-enoic AcidsPresented in part at the autumn meeting of the Swiss Chemical Society in Bern on October 21, 1988.Dedicated to Prof. R. E. Ireland on the occasion of his 60th birthday (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 117-122 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A new method for the preparation of (E)-3-acylprop-2-enoic acids ( = (E)-3-acylacrylic acids) of type II via acid-catalyzed isomerization of the corresponding 3-acylprop-2-ynal acetals of type I (Scheme 1) has been found. The described reaction gives a rapid and quite general access to these compounds known to exhibit a number of interesting biological activities. Some studies toward the elucidation of the reaction mechanism have been made, and a hypothetical mechanism is proposed.
    Zusätzliches Material: 2 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720115
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  • 61
    Digitale Medien
    Digitale Medien
    6-Thia-1-aza-5λ5-phosphabicyclo[3.2.0]hept-3-ene und Isothiocyanatophosphin-sulfide aus (Methylidenamino)phosphinen, Schwefelkohlenstoff und Acetylen- oder Ethylen-Derivaten (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 139-146 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: 6-Thia-l-aza-5λ5-phosphabicyclo[3.2.0]hept-3-enes and Isothiocyanatophosphine-sulfides from (Methylidenamino)phosphines, Carbon Disulfide, and Acetylene- or Ethylene Derivatives(Methylidenamino)phosphines react with carbon disulfide to 1,3,2-thiazaphosphete derivatives 2. Acetylenedicarboxylates give with 2 6-thia-l-aza-5λ5-phosphabicyclo[3.2.0]hept-3-enes 4a, b, and acrylates yield isothio-cyanatophosphin-sulfides 5a-c. The structures of 4a and 5a are proven by an X-ray diffraction analysis.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720118
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  • 62
    Digitale Medien
    Digitale Medien
    C45 und C50-Carotinoide. 6. Mitteilung5. Mitteilung, s. [1]. Synthese eines optisch aktiven cyclischen C20-Bausteins und von Decaprenoxanthin (= (2R, 6R, 2′R, 6′R)-2,2′-Bis(4-hydroxy-3-methylbut-2-enyl)-∊, ∊-carotin) (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 151-157 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: C45- and C50-Carotenoids: Synthesis of an Optically Active Cyclic C20-Building Block and of Decaprenoxanthin ( = (2R, 6R, 2′R, 6′R)-2,2′-Bis(4-hydroxy-3-methylbut-2-enyl)-∊, ∊-carotene)The synthesis of the optically active cyclic C20-building block (R, R)-15 and of the optically active C50-carotenoid (2R, 6R, 2′R, 6′R)-decaprenoxanthin (1) starting from (-)-β-pinene ((S)-2) is reported.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720120
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  • 63
    Digitale Medien
    Digitale Medien
    Formation of the First Trimeric Monoterpenoid Indole Alkaloids (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 147-150 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Under O2, the Aspidosperma alkaloid tabersonine (1) was converted by a crude enzyme preparation from leaves of mature plants of Catharanthus roseus G DON into the trimeric 3-hydroxy-14′-(3α″-tabersonyl)voafrine B (4) which was easily reduced by NaBH4 to 14′-(3α″-tabersonyl)voafrine B ( = tertabersonine; 5). Compounds such as 4 and 5 are the first trimeric alkaloids in the series of monoterpenoid indole alkaloids.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720119
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  • 64
    Digitale Medien
    Digitale Medien
    Polynuclear Iron and Rhodium Complexes of 7-Oxa[2.2.1]hericene (2,3,5,6-tetramethylidenebicyclo[2.2.1]heptan-7-one) (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 158-164 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: μ-Carbonyl(Rh—Rh)di(η5-indenyl)[(2R,3S)-C,2,3,C-η-(2,3,4,5-tetramethylidenebicyclo[2.2.1]heptan-7-one)]]-dirhodium(I)(Rh—Rh) (7) and cis-μ-[(2R,3S,5R,6S))-C,2,3,C-η:C,5,6,C-η-(2,3,5,6-tetramethylidenebicyclo[2.2.1]heptan-7-one)]bis[μ-carbonyldi(η5-indenyl)dirhodium(I)(Rh—Rh)] (8) have been prepared. Complex 7 reacts with Fe2(CO)9 in hexane/MeOH and gives cis-μ-[(2R,3S,5R,6S] (9), trans-μ-[(2R,3S,5S,6R)-C,2,3,C-η: C,5,6, C-η-(2,3,5,6-tetramethylidenebicyclo[2.2.1]heptan-7-one)-μ-carbonyldi(η5-indenyl)dirhodium(I)(Rh—Rh)-(tricarbonyliron) (10), and, μ-carbonyl(Rh—Rh)[(2R,3S)-C,2,3,C-η-(2,3-dimethyl-5,6-dimethylidenebicyclo-[2.2.1]hept-2-en-7-one)]di(η5-indenyl)dirhodium(I)(Rh—Rh) (11). Treatment of 7-oxa[2.2.1]hericene (4) with Fe2(CO)9 or (cyclooctene)2Fe(CO)3 gave a 1:2 mixture of cis-μ-[(2R,3S,5R,6S)-] (12) and trans-μ-[(2R,3S,5S,6R)-C,2,3,C-η:C,5,6,C-η-(2,3,5,6-tetramethylidenebicyclo[2.2.1]heptan-7-one)]bis(tricarbonyliron)(13).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720121
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  • 65
    Digitale Medien
    Digitale Medien
    Eine neue Aminoazirin-Reaktion. Bildung von 3,6-Dihydropyrazin-2(1H)-onen (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 172-179 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A New Aminoazirine Reaction. Formation of 3,6-Dihydropyrazin-2(1H)-onesThe reaction of 3-(dimethylamino)-2H-azirines 1 and 2-(trifluoromethyl)-1,3-oxazol-5(2H)-ones 5 in MeCN or THF at 50-80° leads to 5-(dimethylamino)-3,6-dihydropyrazin-2(1H)-ones 6 (Scheme 3). Reaction mechanisms for the formation of 6 are discussed: either the oxazolones 5 react as CH-acidic heterocycles with 1 (Scheme 4), or the azirines 1 undergo a nucleophilic attack onto the carbonyl group of 5 (Scheme 6). The reaction via intermediate formation of N-(trifluoroacetyl)dipeptide amide 8 (Scheme 5) is excluded.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720123
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  • 66
    Digitale Medien
    Digitale Medien
    Synthesis of the Oviposition-Deterring Pheromone (ODP) in Rhagoletis cerasi L. Preliminary communication (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 165-171 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: For the assignment of the configuration at C(8) and C(15) of the natural oviposition-deterring pheromone 1 in Rhagoletis cerasi L., the four possible stereoisomers of 1 are synthesized. By condensing the C6 building blocks (5R)-4 and (5S)-4 with the boron enolates of the C10 building blocks (4S)-13 and (4R)-13, followed by decarboxylative dehydration, all stereoisomers of 16 are available (Scheme 5). Glucosylation of 16 followed by formation of the taurin amide gives, after deprotection, the four stereoisomers (8R,15S)-1, (8R,15R)-1, (8R,15S)-1, and (8S,15S)-1 (Scheme 6).
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720122
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  • 67
    Digitale Medien
    Digitale Medien
    Mitteilungen (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 185-192 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720125
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  • 68
    Digitale Medien
    Digitale Medien
    New Spermine Alkaloids from Aphelandra tetragona (VAHL) NEESDedicated to Prof. Dr. D. Gröger on the occasion of his 60th birthday (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 180-184 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: 18-O-Methylchaenorpine (1a) and iso-18-O-methylchaenorpine (1b) two novel stereoisomeric spermine alkaloids were isolated from the roots of Aphelandra tetragona (VAHL) NEES. Their structures were established by chemical and spectroscopic studies.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720124
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  • 69
    Digitale Medien
    Digitale Medien
    Masthead (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989) 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720201
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  • 70
    Digitale Medien
    Digitale Medien
    1,5,7-Triazabicyclo[4.4.0]dec-5-en als Reaktionsmedium: Präparativ ergiebige einstufige Herstellung von Etioporphyrin aus Protoporphyrin (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 185-195 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: 1,5,7-Triazabicyclo[4.4.0]dec-5-ene as Reaction Medium: An Efficient One-Step Formation of Etioporphyrine from ProtoporphyrineHeating the commercially available protoporphyrine (4) in molten 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) at 200° for 4 h under exclusion of O2 produces etioporphyrine (6) in 60-70% yield by bisdecarboxylation and concomitant reduction of the two vinyl groups. Mesoporphyrine (5) is bisdecarboxylated to 6 in over 80% yield under these conditions in TBD as well as in DBU as the reaction medium.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720202
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  • 71
    Digitale Medien
    Digitale Medien
    The Chemistry of Thujone. Part XIV.Part XIII [1]. Synthesis of biologically active aryl terpenoid analogues (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 205-212 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Employing thujone-derived intermediates, a series of achiral (9a-d; Scheme 1) and chiral (11b and 11d; Scheme 2) terpene analogues related to the biologically active ‘terpenoid’ hybrids have been prepared. The stereochemistry of the key epoxidation reaction was established by correlation of the product 11b with the previously reported alcohol (R)-20 of known absolute configuration (Scheme 3).
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720204
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  • 72
    Digitale Medien
    Digitale Medien
    Vinyl Carbanions. Part 36.Part 35: [9]. Synthesis of 3-deoxy-D-manno-2-octulosonic acid (KDO) and derivatives (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 213-223 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The β-C-lithiated acrylamide 3A has been proven to be an ideal pyruvate β-carbanion equivalent useful in a highly diastereoselective KDO synthesis. The starting material 3 was prepared from pyruvate diethyl acetal in four convenient steps. Direct lithiation with 2 equiv. of LDA generated the dilithiated species 3A quantitatively. Reaction with 2,3:4,5-di-O-isopropylidene-D-arabinose (11) was highly D-manno-selective. The product 12 was obtained readily from the reaction mixture via crystallization. Ring closure to the butenolide 13, subsequent PhS-group removal with Bu3SnH and pyridinium bromide, and hydrogenolytic debenzylation afforded the known butenolide 19; this KDO precursor gives KDO in two convenient steps. Butenolide 19 was also transformed via two high-yielding steps into the 4,5:7,8-di-O-cyclohexylidene-KDO derivative 22, a valuable starting material for KDO α-glycoside syntheses.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720205
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  • 73
    Digitale Medien
    Digitale Medien
    Colchicine models: Synthesis and Antitubulin Activity of 2′-Monosubstituted and 2′, 5-Disubstituted 2,3,4,4′-Tetramethoxy-1,1′-biphenyls. Synthesis of 4,4′, 5′, 6′-tetramethoxy-1,1′-biphenyl-2,3′-dicarboxylic acidThis paper is dedicated to our friend and colleague Dr. Tetsuji Kametani, Hoshi College of Pharmacy, Tokyo, Japan, who died on October 11, 1988 (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 196-204 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Reductive amination of 2,3,4,4′-tetramethoxtybiphenyl-2-carbaldehyde (4) with MeNH2 afforded methylamine 5 (Scheme 1), Hydroxymethylation of amine 8, prepared similarly from 4 by reductive amination with benzylamine followed by N-methylation, afforded alcohol 12 which was converted the 5-methyl-substituted methylamine 14 by conventional chemical reactions (Scheme 2), Methylamine 14 was also obtained from ester 16 after hydroxymethylation to alcohol 17 and conventional manipulation of alcohol and ester functions (Scheme 2). Both amines 5 and 14 as well as the 2′, 5-dimethyl-substituted biphenyl 26 prepared from the dialdehyde 25 by a Wolff-Kishner reduction, did not show noteworthy activity in the tubulin binding assay or as inhibitors of tubulin polymerization (Table). However, the 2′ethyl-substituted biphebyl 11 prepared from 4 by reaction with MeLi followed by dehyderation and catalytic reduction of styrene 10 (Scheme 1) showed appreciable activity in both assays, coming close to that of known phenyltropolone models. The X-ray analysis of 14·HCl and 11 showed significant difference in the orientation of the rings with respect to one another (Fig.).
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720203
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  • 74
    Digitale Medien
    Digitale Medien
    Biosynthesis of Homoterpenes in Higher Plants (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 247-253 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: In higher plants, the two homoterpenes 4,8-dimethyinona-1,3,7-triene (1) and 4,8,12-trimethyltrideca-1,3,7,11-tetraene (2) are synthesized from the regular terpene alcohols nerolidol and geranyllinalool by fragmentation into the homoterpene and butenone. The biosynthetic pathway is evidenced by conversion of (2H)nerolidol in Hoya purpureo-fusca, Magnolia liliiflora nigra, Robinia pseudoacacia, and Philadelphus coronarius.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720208
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  • 75
    Digitale Medien
    Digitale Medien
    Sphinxolide, a 26-Membered Antitumoral Macrolide Isolated from an Unidentified Pacific Nudibranch (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 237-246 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: It is shown that an unidentified nudibranch of Hawaiian waters contains a 26-membered macrolide, sphinxolide ((-)-1) with potent activity against the KB cell line. The structure of sphinxolide, a 2:1 mixture of (E/Z)-isomers at the formamide moiety, is established to be (-)-1 on the basis of extensive NMR and FAB-MS analysis, in combination with data for the products of mono- (→(-)-2) and diacetylation (→(+)-3).
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720207
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  • 76
    Digitale Medien
    Digitale Medien
    Synthesis of Aristotelia-Type Alkaloids.Part III: [1]. Part IV. Synthesis of (±)-aristoserratineDedicated to Prof. D. Arigoni on the occasion of his 60th birthday (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 254-263 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A convergent diastereoselective synthesis of racemic aristoserratine ((±)-24) via an intramolecular iminium-ion cyclization is described. The pivotal imine (±)-19 was prepared by condensation of the two building blocks (± )-trans-8-amino-3-(2,6-difluorobenzyloxy)-1-p-menthene ((±)-11) and N-(p-methoxybenzenesulfonyl)-3-indo-leacetaldehyde (18) which were synthesized from (±)-trans-1-p-menthene-3,8-diol ((±)-7) and 3-indoleacetic acid, respectively. On the route to the target (±)-24, two previously unknown indole alkaloids have been characterized, namely (±)-‘anti’-hobartin-15-ol ((±)-22) and (±)-‘anti’-aristotelin-15-ol ((±)-23).
    Zusätzliches Material: 1 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720209
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  • 77
    Digitale Medien
    Digitale Medien
    Syntheses of α, β-Epoxy Silyl Ketones (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 264-270 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis of the α, β-epoxy-acylsilanes 1 and 2 starting from the allylic silyl alcohols (E)- and (Z)-3, respectively, by epoxidation with t-BuOOH/VO(acac)2 followed by oxidation with Collins reagent (CrO3/pyridine) in up to 70% overall yields, is described. The acid-catalyzed rearrangement of the epoxy-silyl alcohols 4A + B und 5A + B led to the novel unstable diastereoisomeric α-silyl-β-hydroxy-aldehydes 9 and 10, respectively. The structure of 10 was established by X-ray crystal-structure analysis of the corresponding alcohol 11.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720210
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  • 78
    Digitale Medien
    Digitale Medien
    Spectroscopic Studies of Cyclometallated Pd(II) and Pt(II) Complexes: Optical absorption and emission of single crystals of [Pd(thpy)2] and [Pt(thpy)2] (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 224-236 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The polarized optical absorption and emission (spectra, decay times) of single crystals of [Pd(thpy)2] and [Pt(thpy)2] (thpy ≡ C(3′)-deprotonated form of 2-(2-thienyl)pyridine) at temperatures 1.9 K ≤ T ≤ 80 K are reported. The emission of [Pt(thpy)2] can be influenced strongly by applied magnetic fields (0 ≤ H ≤ 6 T). Depending on the central ions Pd and Pt, the lowest excited electronic states of the single complexes are ligand-centered (LC) states and metal-to-ligand charge transfer (MLCT) states, respectively. This difference leads to distinctly dissimilar properties of the emission of both compounds. The experimental data show that the emission of single crystals of [Pd(thpy)2] and [Pt(thpy)2] at T ≤ 30 K originates from several types of traps (defect states of symmetry 3B2-stabilized below the exciton band) with LC and MLCT character, respectively. In the Pt compound, the 3B2 is split by spin-orbit coupling into three states. The states B1′ and A2′, which determine the emission properties, are separated by Δv ∼ 13 cm-1. Both states can mix under the influence of an applied magnetic field yielding an increase of the emission intensity by a factor of ∼ 1.5 at H = 6 T.
    Zusätzliches Material: 14 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720206
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  • 79
    Digitale Medien
    Digitale Medien
    Total Synthesis of L-Allose, L-Talose, and derivatives.Enantiomerically pure 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives (‘naked sugars’ [2]) as synthetic intermediates, Part IV. Part III, see [1]. (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 278-286 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: (1S, 4R, 5S, 6S)-5-exo, 6-exo-(Isopropylidenedioxy)-7-oxabicyclo[2.2.1]heptan-2-one ((-)-1) was transformed with high stereoselectivity to L-allose. Similarly, enantiomer (+)-1 was transformed into L-talose. The ketones (+)-1 and (-)-1 were derived from furan and 1-cyanovinyl (1S)-camphanate and 1-cyanovinyl (1R)-camphanate, respectively.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720212
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  • 80
    Digitale Medien
    Digitale Medien
    Highly Stereoselective Total Syntheses of 2,5-Anhydro-4-deoxy-D-ribo-hexonic Acid and of (1S)-1-C-(6-amino-7H-purin-8-yl)-1,4-anhydro-3-deoxy-D-erythro-pentitol (= cordycepin C)Enantiomerically pure 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives (‘naked sugars’) as synthetic intermediates, Part V. Part III: [1]. Part IV: [2].Part of the planned Ph. D. thesis of F. G., University of Lausanne.Dedicated to Prof. Hans Dahn on the occasion of his 70th birthday (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 271-277 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Highly regio- and stereoselective monohydroxylation of the C=C bond of (+)-7-oxabicyclo[2.2.1]hept-5-en-2-one (8) was achieved via LiAlH4 reduction of the corresponding 5,6-exo-epoxy dimethyl acetal 9. The reaction gave exclusively (-)-(1R, 2R, 4S)-6,6-dimethoxy-7-oxabicyclo[2.2.1]heptan-2-exo-ol (10) which was transformed into 2,5-anhydro-3-O-benzyl-4-deoxy-D-ribo-hexonic acid (15) and 2,5-anhydro-4-deoxy-D-ribo-hexonic acid (6) via ozonolysis of (-)-(1R, 4S, 6R)-6-exo-benzyloxy-2-{[(tert-butyl)dimethylsilyl]oxy}-7-oxabicyclo[2.2.1]hept-2-ene (14). Cordycepin C (5) was derived from 6 and 4,5,6-triaminopyrimidine using CsF/DMF to generate the adenine heterocycle.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720211
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  • 81
    Digitale Medien
    Digitale Medien
    Die absolute Konfiguration der Iridale und Cycloiridale unterschiedlicher HerkunftDr. G. Ohloff zum 65. Geburtstag mit den besten Wünschen gewidmet (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 287-294 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The Absolute Configuration of Iridals and Cycloiridals of Different OriginNatural irones are known to occur in enantiomeric forms within Iris oils of different origin. They are formed by oxidative degradation of the cycloiridals (C31-triterpenoids) found in rhizomes of various Iris species. The absolute configuration of iridals from different varieties is determined by ozonolysis of the triterpenoids and comparison of their degradation products with authentic samples of known configuration. It is shown that the initial cyclization of squalene resulting in the formation of a monocyclic seco-ring-A iridal has the same stereo-chemical course throughout all Iris species studied. The subsequent cyclization of the homofarnesyl side chain of the iridals, however, produces cycloiridals with enantiomeric irone moieties within different subspecies of the sword lilies.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720213
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  • 82
    Digitale Medien
    Digitale Medien
    Metal Complexes with Macrocyclic Ligands. Part XXVIII.Part XXVII: [1]. Structures and stabilities of the Cu2+ complexes with 1,4,7-triazacyclononane-1-acetic acid (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 307-312 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The potentiometric study of the complexation of 1,4,7-triazacyclononane-l-acetic acid (1) with Cu2+ (I = 0.5 (KNO3), T = 25°) indicates the presence of the species [Cu(1)], [Cu(1)OH], [Cu(1)2], and [(Cu(1))2OH], the stability constants of which are determined. The two complexes [Cu(1)]ClO4 and [(Cu(1)2)OH]ClO4 were also characterized by X-ray structure analysis. In both cases, the Cu2+ ion is in a distorted square-pyramidal arrangement, penta-coordinated by the three N-atoms of the macrocycle, an O-atom of the carboxylate, and an additional O-atom either from a second carboxylate or from an OH-, acting as a bridge between two metal centres.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720215
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  • 83
    Digitale Medien
    Digitale Medien
    Metal Complexes with Macrocyclic Ligands. Part XXIX.Part XXVIII: [1]. Structural and kinetic studies of two isomeric Cu2+ complexes with 1,4-dimethyl-8-[2-(2-pyridyl)ethyl]-1,4,8,11-tetraazacyclotetradecane (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 313-319 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The synthesis and complexation properties of 1,4-dimethyl-8-[2-(2-pyridyl)ethyl]-1,4,8,11-tetraazacyclotetra-decane (2) are described. This ligand forms with Cu2+ two complexes, one of which has been characterized by X-ray structure analysis. The structural, spectral, and kinetic studies indicate that the two Cu2+ complexes are isomers with the macrocycle in the trans-III and trans-I configuration. The rate of the interconversion of the trans-I isomer to the thermodynamically more stable trans-III species is proportional to [OH-]. A mechanism for this reaction is proposed.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720216
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  • 84
    Digitale Medien
    Digitale Medien
    Stereochemical Criteria Providing Unambiguous Experimental Evidence for the intermediacy of ion/molecule complexes in the generation of enolates from gaseous alkoxides. Short communicationDedicated to Prof. Josef Seibl on the occasion of his 65th birthday (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 320-322 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The epimeric alkoxides 6a and 6b, generated in the gas phase by deprotonation of the stereospecifically deuterated isoborneols 5a and 5b, undergo loss of H2 and HD in a 1:1 ratio. This result, ruling out a concerted one-step process, establishes the intermediacy of an ion/molecular complex (‘solvated’ hydride ion) in the course of formation of enolates from the alkoxide anions in the gas phase.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720217
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  • 85
    Digitale Medien
    Digitale Medien
    Neue Dimethinmerocyanin-Farbstoffe mit der (Sulfobutyl)benzothiazol-Gruppe als Donor-Teilchromophor und deren Aggregationsverhalten in wässriger Lösung (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 295-306 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Novel Dimethinemerocyanine Dyes with the (Sulfobutyl)benzothiazole Group as Donor Part of the Chromophor and their Aggregation Tendency in Aqueous SolutionA series of novel dimethinemerocyanine dyes with the (sulfobutyl)benzothiazole group as the donor part of the chromophor is synthesized in good yield and their aggregation tendency in H2O without addition of salt investigated. The merocyanine dye 2b only gives J-aggregation in H2O. The dyes 1a-f and 2a exhibit an intense, red-shifted absorption band due to J-aggregation in H2O in the presence of Me4NCl. In contrast, the dyes 1g and 2c-f show a slightly red-shifted absorption band. The degree of aggregation in H2O is investigated by ultracentrifugation of the representative 2e. Indeed, the slightly red-shifted absorption band in H2O is due to aggregation of ‘oligomers’ of the dye. Contrary to the aggregation of ‘polymers’ of dyes (J-aggregation), we suggest the term ‘K’ band for the slightly red-shifted absorption band. The hemicyanine dye 5 gives the same absorption band in MeOH and in MeOH/H2O 1:3. The dye 11 shows an absorption band in H2O that is probably blue-shifted because of negative solvatochromism. The merocyanine dye 13 gives H-aggregation in H2O.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720214
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  • 86
    Digitale Medien
    Digitale Medien
    Models for Copper-Dioxygen Complexes: The chemistry of copper(II) with some planar tridentate nitrogen ligands (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 323-337 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The solution chemistry of Cu(II) with a series of five planar tridentate nitrogen ligands, 2,6-bis(benzimidazol-2-yl)pyridine (bzimpy, 1), 2,6-bis(l-methylbenzimidazol-2-yl)pyridine (mbzimpy, 2) 2,6-bis(benzothiazol-2-yl) pyridine (bzthpy, 3), 2,6-bis(benzoxazol-2-yl)pyridine (bzoxpy, 4), and 2,2′, 6′, 2″-terpyridyl (terpy, 5) is reported. Electronic and EPR spectra are consistent with the complexes [CuL]2+ having essentially tetragonal structure in solution, with the fourth coordination site in the plane of the ligand occupied by solvent. bzthpy and bzoxpy show smaller ligand-field splittings than bzimpy, mbzimpy, and terpy, and are easily decomplexed from the copper. Substitution of the coordinated solvent molecule in the plane of the ligand is observed with Cl- and OH- (provided that the ligand has no acidic protons) for all ligands except terpy. The reaction between [Cu(mbzimpy)]2+ and imidazole has been studied by potentiometric titration in MeCN/H2O 1:1 and shows strong binding of the imidazole in the plane (log K = 4.5 at 25°), and also the formation of an imidazolate-bridged dinuclear species.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720218
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  • 87
    Digitale Medien
    Digitale Medien
    Synthesis of (-)-Conduritol C (1L-Cyclohex-5-ene-1,2,3/4-tetrol)Enantiomerically pure 7-oxabicyclo[2.2.1]hept-5en-2-yl derivatives (‘naked sugars’ [1]) as synthetic intermediates, Part VI; Part V:[2]. (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 338-347 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: (1R, 2R, 4R)-2-endo-Cyano-7-oxabicyclo[2.2.1]hept-5-en-2-yl acetate ((-)-7) has been transformed into the all-cis-configurated 4L-4,5,6/0-trihydroxycyclohex-2-en-1-one derivatives (-)-12 and (-)-19. (-)-Conduritol C ((-)-3) was derived in a stereospecific manner from (-)-12.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720219
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  • 88
    Digitale Medien
    Digitale Medien
    Diels-Alder-Reaktionen mit 3-Cyclopropylidenprop-1-enyl-ethyl-ether als 1,3-Dien (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 348-352 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Diels-Alder Reactions with 3-Cyclopropylideneprop-1-enyl Ethyl Ether as 1,3-DieneThe title compound undergoes readily Diels-Alder reactions with various dienophiles, especially with quinones. The resulting adducts constitute key intermediates in the synthesis of labdane diterpenoids.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720220
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  • 89
    Digitale Medien
    Digitale Medien
    Synthese von (+)-Abscisinsäure (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 361-364 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Synthesis of (+)-Abscisic Acid.Starting from (4S)-4-hydroxy-2,6,6-trimethylcyclohex-2-enone (2), a short synthesis of the natural (+)-abscisic acid ((+)-1) has been accomplished.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720222
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  • 90
    Digitale Medien
    Digitale Medien
    Ein neuer Zugang zu 2,6,6-Trimethylcyclohexa-2,4-dienon aus 4-Oxoisophoron (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 365-369 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A New Access to 2,6,6-Trimethylcyclohexa-2,4-dienone from 4-Oxoisophorone2,6,6-Trimethylcyclohexa-2,4-dienone (1), a versatile starting material for the preparation of some carotenoids and several natural products, was efficiently (73% yield) prepared from oxoisophorone 3. After conversion of 3 to the alcohol 4 or the acetate 5, H2O was eliminated (4→1) under acidic distillative conditions, whereas AcOH could be eliminated (5→l) under Pd(O) catalysis.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720223
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  • 91
    Digitale Medien
    Digitale Medien
    Neue Zugänge zu einigen aromatischen Retinoiden (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 370-376 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: New Approaches to Some Aromatic RetinoidsStarting from 2,3,5-trimethylphenol (2), two pathways to ethyl (all-E)-9-(4-methoxy-2,3,6-trimethylphenyl)-3,7-dimethylnona-2,4,6,8-tetraenoate (1) and to some of its (Z)-isomers have been developed. The first one is based on a Pd(O)-catalyzed arylation of (Z)-3-methylpent-2-en-4-yn-l-ol (6) with 4-bromo-2,3,5-trimethylanisol (5). The acetylenic C15-alcohol 9 was transformed into the corresponding acetylenic phosphonium salt 10, which was catalytically hydrogenated to the olefinic Wittig salt. Wittig olefination led, then, to the (6Z, 8Z)- and (4Z, 6Z, 8Z)-isomers, 7 and 8, respectively. In a second approach, Friedel-Crafts reaction of 3-methylpent-l-en-4-yn-3-ol with the 2,3,5-trimethylanisol gave a C15-intermediate with a terminal C=C bond in the side chain. After deprotonation and reaction with a C5 aldehyd, the corresponding C20-intermediate could be isolated in high yield. Finally, further conversion led predominantly to the (all-E)-retinoid, accompanied by its (9Z)- and (13Z)-isomers.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720224
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  • 92
    Digitale Medien
    Digitale Medien
    Synthesis of Gossypol AnaloguesDedicated to the memory of Professor Dr. Pierre Crabbé (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 353-360 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Two gossypol analogues 2a and 2b were synthesized for biological evaluation as male contraceptive agents. The naphthol 8c was prepared by analogy with a known procedure starling from 3-isopropylcatechol (3). (t-Bu)2O2-Mediated phenolic coupling of 8c furnished the binaphthol 9c which, after pyrane ring closure, deprotection. and selective bisformylation with SnCl4/Cl2CHOCH3, gave the target compound 2a. The corresponding tetrahydroxy analogue 2b was prepared in a similar way.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720221
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  • 93
    Digitale Medien
    Digitale Medien
    Cyclometalated Compounds of Platinum(II) with two different C, N-aromatic ligands (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 377-382 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A synthetic route leading to bis-heteroleptic cyclometalated complexes is described. The complexes [2-(2′-thienyl)pyridinato-N, C-3′]{2-[3′-(trimethylsilyl)2′-thienyl]pyridinato-N, C3′}platinum(II) ([Pt(thpy) (TMS-thpy)]; I) and (l-phenylpyrazolato-N2, C2′)[2-(2′-thienyl)pyridinato-N, C3′]platinum ([Pt(Phpz)(thpy)]; II) are characterized by UV/VIS, NMR, and mass spectroscopy. Thermal and photochemical oxidative addition reactions yield two out of the 10 possible pairs of enantiomers of octahedral Pt(IV) compounds.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720225
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  • 94
    Digitale Medien
    Digitale Medien
    Masthead (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989) 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720301
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  • 95
    Digitale Medien
    Digitale Medien
    Mitteilungen (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 401-402 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720228
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  • 96
    Digitale Medien
    Digitale Medien
    The Radical Cations of Bicyclo[2.2.1]hepta-2,5-diene (8,9,10-Trinorborna-2,5-diene) and bicyclo[2.2.2]octa-2,5-diene (2,3-Dihydrobarrelene). An ESR and ENDOR studyPart 5 of ‘Applications of ENDOR Spectroscopy to Radical cations in Freon matrices’. Part-4: [1]. (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 383-390 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The radical cation of bicyclo[2-2.1]hepta-2,5-diene (8,9,10-trinorborna-2,5-diene; 1) in CF2ClCFCl2, and CF3CCl3 matrices and that of bicyclo[2.2.2]octa-2,5-diene (2,3-dihydrobarrelene; 2) in CFCl3 and CF3CCl3 matrices have been studied by ESR and ENDOR spectroscopy. For \documentclass{article}\pagestyle{empty}\begin{document}${\bf 1}^{+ \atop \dot{}}$\end{document}, the coupling constants of the olefinic, methano-bridge, and bridgehead protons are -0.780 ±0.005, +0.304±0.002, and -0.049±0.002 mT, respectively. The hyperfine tensor for the methano-bridge protons is axial, Ax = +0.263 ± 0.002 and Ay = +0.386 ± 0.002 mT, while that for the olefinic protons is orthorhombic, Ax = -0.594 ± 0.005, Ay= -0.913 ± 0.005, and Az = -0.834 ± 0.005 mT (x parallel to C—H- z parallel to 2pπ axis). For \documentclass{article}\pagestyle{empty}\begin{document}${\bf 2}^{+ \atop \dot{}}$\end{document}, the coupling constants of the olefinic, ethano-bridge, and bridgehead protons are -0.68 ± 0.01, +0.162 ± 0.005, and -0.108 ± 0.005 mT, respectively. The hyperfine data for \documentclass{article}\pagestyle{empty}\begin{document}${\bf 1}^{+ \atop \dot{}}$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}${\bf 2}^{+ \atop \dot{}}$\end{document} fully support the presentation of their singly occupied orbitals as antisymmetric combinations, b2(π), of the two bonding ethene π-MO's.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720226
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  • 97
    Digitale Medien
    Digitale Medien
    The Allylic Oxidation of Geraniol Catalyzed by Cytochrome P-450Cath., Proceeding with retention of configurationPresented in part at the ‘22nd Reaction Mechanisms Conference’, Pittsburgh, 12.6-16.6.88, at the ‘6th International Conference on Biochemistry and Biophysics of Cytochrome P-450’, Vienna, 3.7.-8.7.88, and at the meeting on the ‘Biocatalytic synthesis of Organic Compounds’, Saratoga Springs, NY, 8.-12.8.88.Dedicated to Prof. D. Arigoni on the occasion of his 60th birthday (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 391-400 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Incubation of the geraniols (R)-(8-2H1)[8-3H1]-1 and (S)-(8-2H1)[8-3H1]-1 with microsomal cytochrome P-450Cath. from the subtropical plant Catharanthus roseus (L.)G. DON resulted in the formation of the chiral 8-hydroxygeraniols (S)-(8-2H1)[8-3H1]-2 and (R)-(8-2H1)[8-3H1]-2. Their absolute configuration was assigned on the basis of the 1H-decoupled 3H-NMR Spectra of the corresponding dicamphanates (S)-(8-2H1)[8-3H1]-9 and (R)-(8-2H1)[8-3H1]-9, of which the configurations are established in relation to the synthetic reference samples. The results clearly indicate retention of configuration during the allylic oxidation of 1.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720227
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  • 98
    Digitale Medien
    Digitale Medien
    Elektrochemische Decarboxylierung von L.-Threonin- und Oligopeptid-Derivaten unter Bildung von N-Acyl-N, O-acetalen: Herstellung von Oligopeptiden mit Carboxamid-oder Phosphonat-C-TerminusTeilweise in einer Kurzmitteilung erwähnt (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 401-425 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Electrochemical Decarboxylation of L-Threonine and Oligopeptide Derivatives with Formation of N-Acyl-N, O-acetals: Preparation of Oligopeptides with Amide or Phophonate C-TerminusDerivatives of α-amino acids with two stereogenic centers (cf. L-threonine) and of di-, tri-, and tetrapeptides are electrolyzed in MeOH or AcOH, with formation of N-acyl-N, O-acetals (1b-15b, 20b), in an anodic oxidative substitution of the COOH by an OR group. The amine ends of the oligopeptides may be benzyloxycarbonyl(Z)- or (tert-butoxy)carbonyl(Boc)-protected. With unprotected dipeptides, an electrolytic decarboxylative cyclization to imidazolidinones (18c, 19c) may also occur (in H2O/NH4OAc). The electrolyses are carried out in simple flasks with cooling jackets (‘undivided cell’), using constant current conditions and anodes of Pt or glassy C. The electrolyte is generated in situ by adding 10-20 mol-% of a tertiary amine. Mild acidic hydrolysis of electrolysis products thus obtained may lead to amino-acid amides or peptide amides (10c, 11c, 12c, 17c) with one amino acid less than the starting material. The N, O-acetals from L-threonine and the oligopeptides also react with organometallic nucleophiles such as Grignard compounds (→21-26, 29), with formation of products in which the original COOH group has been replaced by alkyl or allyl (sometimes even with moderate stereoselectivity). By treatment of the peptide-derived (open-chain) N, O-acetals with trialkyl or triaryl phosphites/TiCl4 the RO group is replaced by a phosphodiester group in a (non-diastereoselective) Michaelis-Arbuzov-type reaction (1d, 1e, 2d-9d, 5e). Thus, the two-step sequence of electrolysis and phosphonation converts an oligopeptide derivative to an analogue with a phosphonic-acid end group. The diastereoisomeric N-protected dimethyl and diethyl dipeptidephosphonates (also prepared from the corresponding diaryl esters by Ti(OR)4-mediated transesterification) could be separated by preparative HPLC (SiO2, Lichrosorb Si 60, 10 μm); the dextrorotatory isomers of 1d-3d were assigned L, D-, the laevoratory ones L, L-configuration by hydrolysis to and identification of the known amino and aminophosphonic acids. The results described demonstrate a new simple route leading, from a given oligopeptide, to pure peptide analogues of known configuration.
    Notizen: No abstract.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720302
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  • 99
    Digitale Medien
    Digitale Medien
    Acid-Catalyzed Cyclization Reactions of Substituted Acetylenic Ketones: A new Approach for the Synthesis of 3-Halofurans, Flavones, and StyrylchromonesPresented in part at the autumn meeting of the Swiss Chemical Society in Bern on October 21, 1988. (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 447-456 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Acetylenic acetals of type I (Scheme 1) and acetylenic ketones of type III (Scheme 1), 37 and 38 (Scheme 7) are versatile synthetic precursors for the synthesis of various heterocycles by acid-catalyzed cyclization reactions. By this way, substituted 3-halofurans of type II and IV (Scheme 1) and flavones and styrylchromones (Scheme 7) can be synthesized in good-to-excellent yields. The high degree of regioselectivity in the synthesis of the 3-halofurans (Scheme 4) is the result of the regioselective β-addition of HX (X = Cl, Br, I) to the acetylenic aldehyde and acetylenic ketone moieties. A possible mechanism is depicted in Scheme 5. Since 3-halofurans can easily be metalated and substituted, this approach constitutes a new synthesis of highly substituted furans.
    Zusätzliches Material: 3 Tab.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720305
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  • 100
    Digitale Medien
    Digitale Medien
    Stoffwechselprodukte von Mikroorganismen. 253. Mitteilung252, Mitteilung. Hormaomycin, ein neues Peptid-lacton mit morphogener Aktivität auf Streptomyceten (1989)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 72 (1989), S. 426-437 
    Details
    ISSN: 0018-019X
    Schlagwort(e): Chemistry ; Organic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Hormaomycin, a Novel Peptide Lactone with Morphogenetic Activity on StreptomycesA culture identified as Streptomyces griseoflavus (strain W-384) has been found to produce a novel peptide-lactone antibiotic designated hormaomycin (6). The empirical molecular formula of the compound is established to be C55H69ClN10O14. The constituent amino acids of the antibiotic are suggested to be allothreonine (1; 1), isoleucine (2; 1), 3-methyl-phenylalanine (3; 2), and, for the first time identified from a natural source, 4-[(Z)-prop-1-enyl]-proline (4; 1) and 3-(2-nitrocyclopropyl)-alanine (5; 2). The amino acids were delivered by acidic hydrolysis and assigned by high-resolution- GC/MS analysis (after transformation to derivatives) in combination with extended 2D-NMR experiments of the antibiotic itself. From the latter, it became plausible that the N-terminus of the peptide chain is acylated by a Cl-containing derivative of 1H-pyrrol-2-carboxylic acid. Hormaomycin is active against some Gram-positive bacteria. In addition, the antibiotic exhibits potent aerial mycelium-inducing activity and effects the production of antibiotics.
    Notizen: No abstract.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/hlca.19890720303
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