7alpha-Hydroxy-DHEA → HCID 56620856, compound

Participants

Reaction Steps

Reaction of the less hindered 3β-hydroxy-5α-androstan-17-one 1 with t-butyldimethylsilyl chloride yields the 3β-t-butyldimethylsilyl ether 2. Treatment of this first with catechol phosphochloridate followed by displacement with iodine yields 3β-hydroxy-11β-iodo-5α-androstan-17-one 3-dimethyl-t-butylsilyl ether 3. Protection of the C-17 ketone as the 1,3-dioxolane 4 followed by alkenylation using dialkenyl dilithio cyano cuprate, (RCH=CH)2Cu(CN)Li2 yields 11α-alkenyl-3β-hydroxy-5α-androstan-17-one-3-t-butyldimethylsilyl ether 5. Deprotection of the C-17 ketone and 3β alcohol affords 11α-alkenyl 3β-hydroxy-5α-androstan-17-one 6. If 6 has R=2'-tri-n-butylstannyl ethenyl, then lead tetraacetate oxidation affords 11α-alkynyl-3β-hydroxy-5α-androstan-17-one. 6, (R=C≡CH). ##STR58##

Provenance & Evidence