Bufadienolides. 3. A synthetic route to isocardenolides

George Pettit, Brian Green, Arun K. Das Gupta, Philip A. Whitehouse, John P. Yardley

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

A Bestmann reaction employing 3β-acetoxy-20-oxo-21-iodo-5-pregnene (2) and carbomethoxymethylenetriphenylphosphorane was used to complete a synthesis of methyl 3β-acetoxy-2-oxo-21-nor-5-trans-22-choladienate (1), which upon irradiation in sunlight gave cis isomer 5. Similarly, 3β-acetoxy-20-oxo-21-iodo-5,16-pregnadiene (6) was converted into trans side-chain olefin 7 and cis side-chain olefin 8. Palladium-catalyzed hydrogenation of triene 8 resulted in methyl 3β-acetoxy-20-oxo-21-nor-5α-cholanate (9a) accompanied by small amounts of the corresponding 3-deoxy derivative 9b and 3β-acetoxy-20-hydroxy-21-nor-5α-cholanic acid γ-lactone (24 → 20). Subjecting triene 8 to sodium borohydride reduction in ethanol yielded isocardanolide 10. The principal objective, synthesis of isocardenolide 11, was realized by selective reduction of ketone 5 with sodium borohydride in dimethylformamide.

Original languageEnglish (US)
Pages (from-to)1381-1384
Number of pages4
JournalJournal of Organic Chemistry
Volume35
Issue number5
StatePublished - 1970

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Bufanolides
Alkenes
Pregnadienes
Pregnenes
Dimethylformamide
Palladium
Lactones
Ketones
Isomers
Hydrogenation
Ethanol
Irradiation
Derivatives
sodium borohydride

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Pettit, G., Green, B., Das Gupta, A. K., Whitehouse, P. A., & Yardley, J. P. (1970). Bufadienolides. 3. A synthetic route to isocardenolides. Journal of Organic Chemistry, 35(5), 1381-1384.

Bufadienolides. 3. A synthetic route to isocardenolides. / Pettit, George; Green, Brian; Das Gupta, Arun K.; Whitehouse, Philip A.; Yardley, John P.

In: Journal of Organic Chemistry, Vol. 35, No. 5, 1970, p. 1381-1384.

Research output: Contribution to journalArticle

Pettit, G, Green, B, Das Gupta, AK, Whitehouse, PA & Yardley, JP 1970, 'Bufadienolides. 3. A synthetic route to isocardenolides', Journal of Organic Chemistry, vol. 35, no. 5, pp. 1381-1384.
Pettit G, Green B, Das Gupta AK, Whitehouse PA, Yardley JP. Bufadienolides. 3. A synthetic route to isocardenolides. Journal of Organic Chemistry. 1970;35(5):1381-1384.
Pettit, George ; Green, Brian ; Das Gupta, Arun K. ; Whitehouse, Philip A. ; Yardley, John P. / Bufadienolides. 3. A synthetic route to isocardenolides. In: Journal of Organic Chemistry. 1970 ; Vol. 35, No. 5. pp. 1381-1384.
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