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Synthesis of [14α-methyl-3H]-24,25-dihydrolanosterol

✍ Scribed by Steve Dekeczer; Denis Kertesz; Howard Parnes

Publisher
John Wiley and Sons
Year
1993
Tongue
French
Weight
661 KB
Volume
33
Category
Article
ISSN
0022-2135

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✦ Synopsis

Abstract

We describe, herein, the first synthesis of isomerically pure title compound (6) at high specific activity. This required the development of a convenient, regiospecific synthesis of the Δ^8(9)^‐15‐ketone (15) and subsequent alkylation with methyl‐[^3^H~3~] iodide. A key step in our procedure was the use of an electrochemical reduction of the intermediate [14α‐methyl‐^3^H]‐ 15‐oxo ‐dihydrolanosterol (19). This process was effected cleanly and in high yield to give (6), an important assay tool in the search for cholesterol lowering agents. This approach was found to be significantly superior to the Wolff‐Kishner reduction of the corresponding 3‐benzoate (18).

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