Construction of the 1,2-dialkenylcyclohexane framework via Ireland-Claisen rearrangement and intramolecular Barbier reaction: application to the synthesis of (±)-Geijerone and a diastereoisomeric mixture with its 5-epimer.
The elemene-type terpenoids, which possess various biological activities, contain a syn- or anti-1,2-dialkenylcyclohexane framework. An efficient synthetic route to the syn- and anti-1,2-dialkenylcyclohexane core and its application in the synthesis of (±)-geijerone and its diastereomer is reported. Construction of the syn- and anti-1,2-dialkenyl moiety was achieved via Ireland-Claisen rearrangement of the (E)-allylic ester, and the cyclohexanone moiety was derived from the iodoaldehyde via intramolecular Barbier reaction. The synthetic strategy allows rapid access to various epimers and analogues of elemene-type products.
Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China. ldawei@yahoo.com.
Dawei
D
Liang
Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China. gaonana89@126.com.
Nana
N
Gao
Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China. lwnever@126.com.
Wei
W
Liu
Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, Liaoning, China. dongjh66@hotmail.com.
Jinhua
J
Dong
D000080462:Acyclic Monoterpenes; D003500:Cyclization; D003512:Cyclohexanones / Q000138:chemical synthesis*; D004951:Esterification; D010084:Oxidation-Reduction; D012717:Sesquiterpenes / Q000138:chemical synthesis*; D013237:Stereoisomerism; D013729:Terpenes / Q000737:chemistry
D000080462:Acyclic Monoterpenes; D003512:Cyclohexanones; D012717:Sesquiterpenes; D013729:Terpenes; C002207:geijerone; C007836:geraniol