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
  • 1
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaktionen von Uracilen, 4. - Einige Aspekte der Chemie von Pyrido[2,3-d]pyrimidinen. Ein neues s-Triazolo[4′, 3′ : 1,6]pyrido[2,3-d]pyrimidinAus dem neuen 7-Hydrazino-1,3-dimethylpyrido[2,3-d]pyrimidin-2,4(1H,3H)-dion (2) werden die Hydrazinderivate 3, 5, 6, 8 und 10 dargestellt. Aus 3 wird das s-Triazolo[4′,3′: 1,6]pyrido-[2,3-d]pyrimidin 4 erhalten, während Ringschlußversuche von 5, 6 und 8 erfolglos blieben. Zwei 6-substituierte Pyrido[2,3-d]pyrimidine werden hergestellt, 13a aus 11 und Benzoylacetonitril, 16 durch Photo-Fries-Umlagerung von 15. In CDCl3-Lösung und in fester Phase überwiegt die tautomere OH-Form 161.
    Notes: The novel 7-hydrazino-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione (2) gives the hydrazine derivatives 3, 5, 6, 8, and 10. The s-triazolo[4′,3′: 1,6]pyrido[2,3-d]pyrimidine 4 is prepared from 3, while the attempted cyclizations of 5, 6, and 8 failed. Two pyrido[2,3-d]pyrimidines substituted in position 6 are prepared, 13a from 11 and benzoylacetonitrile, 16 by photo-Fries rearrangement of 15. In CDCl3 solution and in solid phase predominates the tautomeric OH form 161.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 943-949 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaktionen von Uracilen, 7. Synthese und eine neue Sequenz thermischer [1,5]-sigmatroper Umlagerungen von 6-(Alkylamino)-5-ethenyluracilenNeue 6-(Alkylamino)-5-ethenyluracile (2d und 7) werden dargestellt, um Substituenteneffekte bei thermischen Reaktionen zu untersuchen. Ähnlich 2a werden 2d und 7 beim Erhitzen in Dowtherm® A und nach anschließender Verseifung in die 6-Amino-5-(ethoxycarbonyl[phenyl]ethyl)uracile 4 bzw. 8 übergeführt. Erhitzen in Xylol liefert die intermediären Imine 11 und 12. Deuterierungsexperimente belegen aufeinanderfolgende thermische [1,5]-H-Wanderungen (2a-D1 → 4-D1 und 4-D2; 2a′-D2 → 4′-D1). Die Mechanismen werden diskutiert.
    Notes: Additional 6-(alkylamino)-5-ethenyluracils (2d, 7) have been prepared for investigating substituent effects in thermal reactions. Like 2a, upon heating in Dowtherm® A 2d and 7 afford after saponification 6-amino-5-(ethoxycarbonyl[phenyl]ethyl)uracils 4 and 8, respectively. After refluxing in xylene the intermediary imines 11 and 12 can be isolated. Deuteration experiments reveal consecutive thermal [1,5]H-migrations (2a - D1 → 4-D1, and 4-D2; 2a′-D2 → 4′-D1). The mechanism is discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0020-7608
    Keywords: pharmacophore ; DISCO ; conformational analysis ; antiarrhythmic agents ; dofetilide ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Blockade of cardiac-delayed rectifier potassium current (IKr) is an important mechanism for Class III antiarrhythmic effect. We developed pharmacophores for IKr inhibitors starting from structures of known blockers. To obtain the pharmacophores, DISCO module of SYBYL was used. Conformations required for DISCO computations were provided by Multisearch type conformational analyses. A common five-point three-dimensional relationship was identified for the most active compounds, whereas a four-point pharmacophore forming a subset of the former one, could be developed for less potent agents.   © 1998 John Wiley & Sons, Inc. Int J Quant Chem 69: 21-30, 1998
    Additional Material: 5 Ill.
    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...