SHORT-STEP STEREOSELECTIVE SYNTHESIS OF PHA,22-TRIACETOXY-23,24-DINOR-5-ALPHA-CHOLAN-6-ONE - KEY INTERMEDIATE FOR THE PREPARATION OF 24(1)-NORBRASSINOLIDE, DOLICHOLIDE AND DOLICHOSTERONE

Authors
HAZRA BG PORE VS JOSHI PL
Citation
Bg. Hazra et al., SHORT-STEP STEREOSELECTIVE SYNTHESIS OF PHA,22-TRIACETOXY-23,24-DINOR-5-ALPHA-CHOLAN-6-ONE - KEY INTERMEDIATE FOR THE PREPARATION OF 24(1)-NORBRASSINOLIDE, DOLICHOLIDE AND DOLICHOSTERONE, Journal of the Chemical Society. Perkin transactions. I, (15), 1993, pp. 1819-1822
Citations number
24
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
Journal of the Chemical Society. Perkin transactions. I → ACNP
ISSN journal
0300922X
Issue
15
Year of publication
1993
Pages
1819 - 1822
Database
ISI
SICI code
0300-922X(1993):15<1819:SSSOP>2.0.ZU;2-R
Abstract
A stereoselective synthesis of o-23,24-dinor-5alpha-cholan-2alpha,3alp ha,22-triyl triacetate 9 was achieved in 44% overall yield in nine ste ps starting from 3beta-hydroxyandrost-5-en-17-one 8. The important fea tures of this synthesis are the modified Wittig reaction on the 17-oxo steroid 8 and the stereospecific generation of the chiral centre at C -20 by a resin-catalysed ene reaction on (Z)-3beta, p-tolylsulfonyloxy pregna-5,17(20)-diene 11.