Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles: DFG German National Licenses  (4)
  • 1985-1989  (4)
  • 1940-1944
  • Organic Chemistry  (4)
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 329 (1987), S. 349-354 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of 3-Substituted 8(14)-Unsaturated 5β-Estranes
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Cyclofunctionalization of 2-Allyl-phenols with Sulfur Chlorides. Synthesis of 2,3-Dihydrobenzofurfuryl Thioethers by the Reaction of 2-Allyl-phenols with Aromatic Sulfenyl ChloridesReactions of different substituted 2-allyl-phenols (2a-h) with either phenylsulfeny chloride (3) or 4-methyl phenylsulfenyl chloride (4) yield the products of a cyclofunctionali zation 2-phenylthiomethyl 2,3-dihydrobenzofuranes (6a-h) or 2-(4′-methylphenyl) 2,3-dihydrobenzofurane (7a-g), respectively. The identification of the products was carried out by mass spectroscopy and 1H-n.m.r.-spectroscopy. Isomeric compounds, i.e. 3-phenylthio 2,3-dihydrobenzopyranes (10) were not obtained. The reaction is Markovnilov-directed. In the case of the treatment of 2-allyl-phenols with 2-nitro phenylsulfenyl chloride (5) we have obtained mixtures of 2-(2′-nitrophenyl) thiomethyl 2,3-dihydrobenzofuranes (8a-d) and of simple Markovnikov adducts, so-called β-chlorothioethers. The mixtures were identified by 1H-n.m.r.- and mass spectroscopic (9a-d) methods.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1985 (1985), S. 1216-1222 
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Question of the Planarity of 9,10-Anthraquinone DerivativesIn the crystalline state 11,11,12,12-tetracyano-9,10-anthraquinodimethane [3a, X = C(CN)2] shows a molecular geometry, which strongly deviates from the planar parent compound anthraquinone. The angle between the benzoannulands is 145°: the dicyanomethylene units are folded in the opposite direction and include an angle of about 120°. Contrary to this, syn-N,N′-dicyano-2,3-dimethyl-9,10-anthraquinonediimine (3b, X = N - CN) is nearly planar. Steric interactions between the NCN moieties and the hydrogen atoms of the anthraquinone skeleton are reduced by tilting of the N - CN substituent within the molecular plane (angles C-C=N 127.0 and 114.3°).
    Notes: 11,11,12,12-Tetracyan-9,10-anthrachinodimethan [3a, X = C(CN)2] besitzt im Kristall eine stark von der Planarität der Stammverbindung Anthrachinon abweichende Geometrie. Der Winkel zwischen den beiden Benzoanellanden beträgt 145°; die Dicyanmethylen-Einheiten sind entgegengesetzt gefaltet und schließen einen Winkel von ca. 120° ein. Im Gegensatz dazu ist syn-N,N′-Dicyan-2,3-dimethyl-9,10-anthrachinondiimin (3b, X = N-CN) nahezu planar. Sterische Wechselwirkungen der N-CN-Gruppierung mit den Wasserstoffatomen des Anthrachinon-Grundgerüstes werden durch Kippen des N-CN-Substituenten in der Molekülebene vermindert (Winkel C-C=N 127.0 und 114.3°).
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Aminoglycosid-Antibiotika - Fortamin-Aglyca Totalsynthese, Racemattrennung, chemischen ModifizierungenAusgehend von Dianhydro-epi-inosit 10 (letztlich erhältlich aus Benzol) wurde eine leistungsfähige Synthese für enantiomerenreine (+)/(-)-Des-O-methylfortamine (Derivate) entwickelt. Zentrale Schritte sind die regiospezifischen Epoxidöffnungen, intramolekular beim Diepoxybis(urethan) 11 und intermolekular mit (+)-1-Phenylethylamin bei den Epoxyurethanen rac-13. Die diastereomeren Addukte (30, 32) können verlustfrei durch Kristallisation/Chromatographie getrennt werden. Nach hydrierender Spaltung werden natürliche und nicht natürliche cis-1,4-Inosadiamine enantiomerenrein erhalten [z. B. Fortamin (-)-1, ent-Fortamin (+)-1, 3-O-Desmethylfortamin (-)-38, ent-3-O-Desmethylfortamin (+)-380]. Der in zahlreichen Modellreaktionen optimierte Syntheseweg erlaubt breite chemische Modifizerungen und führt u.a.zu 3-O-Desmethylfortamin- und ent-Fortamin-Derivaten, in denen nur die zur Glycosidierung gebrauchte (6)4-OH-Gruppe ungeschützt bleibt.
    Notes: Starting from the dianhydro-epi-inositol 10 (available ultimately from benzene) an expedient total synthesis of enantiomerically pure (+)/(-)-de-O-methylfortamines (derivatives) has been developed. Key steps are the regiospecific epoxide openings which occur intramolecularly in the diepoxybis(urethane) 11 and intermolecularly by (+)-1-phenylthylamine in the epoxyurethanes rac-13. The diastereomeric adducts (30, 32) are quantitatively separated by crystallization/chromatogrphy. Following hydrogenation, natural and nonnatural cis-1,4-inosadiamines are obtained optically pure [e.g. fortamine (-)-1, ent-fortamine (+)-1, 3-O-demethylfortamine (-)-38, ent-3-O-demethylfortamine (+)-38]. This approach, which was optimized by numerous model reactions, allows wide chemical modifications and leads among others to 3-O-demethylfortamine and ent-fortamine derivatives in which only the (6)4-OH-group, the one to be glycosidated, remains unprotected.
    Additional Material: 9 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...