Synthesis of the 5-7-6 core of guanacastepenes. Construction of C8 quaternary carbon via the inversion of stereochemistry.
[formula: see text] An efficient and unique route to the 5-7-6 core of guanacatepene A (1) is described. The installation of the desired stereochemistry at the C8 position was achieved via the desymmetrization of the cyclohexadienone by reductive ring closure of the seven-membered ring. That the closure of the seven-membered ring produced only the desired isomer is hypothesized to be a result of the more stable trans relationship between the C8 and C11 methyl groups.
Nguyen
Truc M
TM
Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Seifert
Robert J
RJ
Mowrey
Dale R
DR
Lee
Daesung
D
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis*; D003500:Cyclization; D003510:Cyclohexanes / Q000737:chemistry; D053138:Cyclohexenes; D004224:Diterpenes / Q000138:chemical synthesis*; D013237:Stereoisomerism
D000900:Anti-Bacterial Agents; D003510:Cyclohexanes; D053138:Cyclohexenes; D004224:Diterpenes; C454620:guanacastepene A; C048401:1,4-cyclohexadiene