| abstract |
Disclosed is a process for producing compound C represented by formula C:n nwherein R' represents straight chain, branched chain, or cyclic C 2-6 alkylcarbonyl, wherein R 1b is used as a protective group for hydroxyl at the 7-position of compound C. R 1b represents formyl; optionally substituted straight chain C 1-4 alkylcarbonyl; optionally substituted benzyl; group -SiR 3 R 4 R 5 optionally substituted by halogen atom wherein R 3 , R 4 , and R 5 each independently represent straight chain or branched chain C 1-6 alkyl or phenyl; C 1-6 alkyloxy-C 1-6 alkyl optionally substituted by halogen atom; C 1 - 6 alkylthio-C 1-6 alkyl optionally substituted by halogen atom; straight chain, branched chain, or cyclic C 1-4 alkyl optionally substituted by halogen atom, provided that, when alkyl in the C 1-4 alkyl group is of a branched chain or cyclic type, the alkyl group is C 3-4 alkyl; C 2-6 alkenyl optionally substituted by halogen atom; C 2-6 alkynyl optionally substituted by halogen atom; or an optionally substituted saturated or unsaturated five- or six-membered heterocyclic group. The process can produce pyripyropene derivatives that have acyloxy groups at the 1- and 11-positions and a hydroxyl group at the 7-position and are useful as insect pest control agents at a high yield. |