PROCESS FOR PREPARATION OF MK-7 TYPE OF VITAMIN K2

摘要

Process for preparation of MK-7 type of vitamin K2 is characterized by attaching hexaprenyl chain of all-trans configuration to monoprenyl derivative of menadiol following 1+6 synthetic strategy. According to the invention, a-sulfonyl carbanion generated in situ from the protected monoprenyl menadiol of the formula (II), wherein R1 represents C1-3-alkyl group, is reacted with hexaprenyl halide of the formula (VII), wherein X represents halogen atom, preferably bromine, both Z and Z represent H or one of Z and Z represents H and the other represents phenylsulfonyl group SO2Ph in the alkylation reaction. The hexaprenyl halide of formula (VII) is obtained by coupling two triprenyl units in alkylation reaction, with or without separation of the intermediates.