Synthesis of Guaia-4(5)-en-11-ol, Guaia-5(6)-en-11-ol, Aciphyllene, 1-epi-Melicodenones C and E, and Other Guaiane-Type Sesquiterpenoids via the Diastereoselective Epoxidation of Guaiol
摘要:
The diastereomeric ratio of epoxidation of the internally bridged carbon-carbon double bond of guaiol (1a) is strongly influenced by the combined effects of the types of remote protecting groups on the hydroxyisopropyl side chain, choice of solvent, and epoxidizing reagent. This observation has allowed us to devise concise stereoselective syntheses of a range of guaiane-type sesquiterpenoids via an epoxidation, ring-opening/elimination, and functionality manipulation sequence. Natural products guaia-4(5)-en-11-ol (2a), guaia-5(6)-en-11-ol (3), and aciphyllene (4a) and epimers of the recently isolated natural products, 1-epi-guaia-4(5)-en-11-ol (2b), 1-epi-aciphyllene (4b), and 1-epi-melicodenones C (5a) and E (6a), were synthesized in good yields in relatively few steps.
The present invention relates to the use of geraniol or any of its saturated or unsaturated monoterpene derivatives as a bacterial efflux pump inhibitor, for reducing antibiotic or antiseptic resistance or restoring antibiotic or antiseptic sensitivity to an antibiotic or antiseptic-resistant bacterial strain.
Synthesis of Guaia-4(5)-en-11-ol, Guaia-5(6)-en-11-ol, Aciphyllene, 1-<i>epi</i>-Melicodenones C and E, and Other Guaiane-Type Sesquiterpenoids via the Diastereoselective Epoxidation of Guaiol
作者:An-Cheng Huang、Christopher J. Sumby、Edward R. T. Tiekink、Dennis K. Taylor
DOI:10.1021/np500611z
日期:2014.11.26
The diastereomeric ratio of epoxidation of the internally bridged carbon-carbon double bond of guaiol (1a) is strongly influenced by the combined effects of the types of remote protecting groups on the hydroxyisopropyl side chain, choice of solvent, and epoxidizing reagent. This observation has allowed us to devise concise stereoselective syntheses of a range of guaiane-type sesquiterpenoids via an epoxidation, ring-opening/elimination, and functionality manipulation sequence. Natural products guaia-4(5)-en-11-ol (2a), guaia-5(6)-en-11-ol (3), and aciphyllene (4a) and epimers of the recently isolated natural products, 1-epi-guaia-4(5)-en-11-ol (2b), 1-epi-aciphyllene (4b), and 1-epi-melicodenones C (5a) and E (6a), were synthesized in good yields in relatively few steps.