Bufadienolides. 1. Introduction and base-catalyzed condensation of methyl ketones with glyoxylic acid

George Pettit, Brian Green, George L. Dunn

Research output: Contribution to journalArticle

32 Citations (Scopus)

Abstract

Introduction to a series of contributions pertaining to syntheses of isocardenolides, cardenolides, isobufadienolides, and bufadienolides is presented. A comprehensive study of an aldol condensation between glyoxylic acid and various methyl ketones is described. At high hydroxyl ion concentration, methyl β-naphthyl ketone gives bis(β-naphthacyl)acetic acid (11a), but by careful control of pH the condensation can be directed to yield the γ-ketoacrylic acid 16a and/or a mixture of α-hydroxy-γ-oxobutyric acid (15a) and α-methoxy-γ-oxobutyric acid (17a). The reaction is applied to methyl cyclopentyl ketone, 2,5-dimethoxyacetophenone, 2,4-dimethyl-acetophenone, pinonic acid (18), and the steroidal ketones, 3β-hydroxy-20-oxo-5-pregnene (7a) and 3β-hydroxy-20-oxo-5α-pregnane (24a).

Original languageEnglish (US)
Pages (from-to)1367-1376
Number of pages10
JournalJournal of Organic Chemistry
Volume35
Issue number5
StatePublished - 1970

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Bufanolides
Ketones
Condensation
Acids
Pregnenes
Cardenolides
Pregnanes
Acetic Acid
glyoxylic acid

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Bufadienolides. 1. Introduction and base-catalyzed condensation of methyl ketones with glyoxylic acid. / Pettit, George; Green, Brian; Dunn, George L.

In: Journal of Organic Chemistry, Vol. 35, No. 5, 1970, p. 1367-1376.

Research output: Contribution to journalArticle

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