Totalsynthese optisch aktiver Steroide. XIII. Mitteilung. Synthese von 4,9(11)-Androstadien-3,17-dion

✍ Scribed by Ulrich Eder; Gerhard Sauer; Gregor Haffer; Jürgen Ruppert; Rudolf Wiechert; Andor Fürst; Werner Meier

• Publisher: John Wiley and Sons
• Year: 1976
• Tongue: German
• Weight: 474 KB
• Volume: 59
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.19760590404

✦ Synopsis

Synthesis of 4,9(11)‐androstadiene‐3,17‐dione.

The total synthesis of 4,9(11)‐androstadiene‐3,17‐dione (23) is described starting from (1 S, 7 a__S__)‐1‐t‐butoxy‐7a‐methyl‐5,6,7,7a‐tetrahydroindan‐5‐one (8) as a CD‐building block. The key step involves alkylation of 8 with 1‐chloro‐7,7‐o‐phenylenedioxy‐octane‐3‐one (14) a novel AB‐synthon to give the diketone 15. 15 is converted to the secosteroid 20 via the diene enol ether 17 using a previously described procedure. Low temperature methylation of 20 affords predominantly the 10β‐methyl compound 21, which is readily transformed into the title dione 23.