Reduction of α-diazo-β-hydroxy esters to β-hydroxy esters: application in one of two convergent syntheses of a (22S)-22-hydroxy bile acid from fish bile and its (22R)-epimer
- 1 January 1985
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of the Chemical Society, Perkin Transactions 1
- No. 3,p. 493-497
- https://doi.org/10.1039/p19850000493
Abstract
α-Diazo-β-hydroxy esters (3) prepared by condensation of aldehydes (1) with ethyl (lithio) diazoacetate (2) are reduced with 5% palladium over charcoal in methanol into the corresponding β-hydroxy esters (5) in high yield. This sequence is applied to a new synthesis of haemulcholic acid (14c), a (22S)-22-hydroxy bile acid from fish bile and its (22R)-epimer (14d). A convergent synthesis of (14c), a (22S)-22-hydroxy bile acid from fish bile and its (22R)-epimer (14d). A convergent synthesis of (14c) and (14d) involves, as a key step, the dirhodium (II) tetra-acetate conversion of (12) into the corresponding β-keto ester (13).This publication has 2 references indexed in Scilit:
- Synthesis of (22R and 22S)-3 alpha, 7 alpha, 22-trihydroxy-5 beta-cholan-24-oic acids and structure of haemulcholic acid, a unique bile acid isolated from fish bile.Journal of Lipid Research, 1981
- Lithium‐diazoessigsäure‐äthylesterAngewandte Chemie, 1970