NEW 16-MEMBERED RING MACROLIDE DERIVATIVE AND ITS EFFICIENT PRODUCTION PROCESS

摘要

PURPOSE:To obtain a new 16-membered ring macrolide derivative useful e.g. as an antibacterial agent effective against Gram-positive bacteria by using an acetal-based substituent having asymmetric carbon as a protecting group of the 9-hydroxyl group of the lactone ring of a 16-membered ring magrolide derivative. CONSTITUTION:A new 16-membered ring macrolide derivative (salt) is expressed by formula I (R<1> is a 1-3C alkyl; R<2> is H or a substituent modifying or protecting a hydroxyl group; R<3> is H or a 2-5C aliphatic acyl) and ha)' antibacterial action effective against Gram-positive bacteria. The compound can be produced in high efficiency by using a compound (salt) expressed by formula II (R<4> is a 2-5C aliphatic acyl) as a starting raw material, protecting the 9-hydroxyl group of the lactone ring of the compound with an acetal-based substituent having asymmetric carbon (e.g. 1-ethoxyethyl, tetrahydrofuranyl or tetrahydropyranyl) and methylating the 3''-hydroxyl group.