Abstract
The condensation of 6', 7-bis(benzoyloxy)-2', 4'-dimethoxyisolfavone (18) with 2-methyl-3-buten-2-ol, followed by hydrolysis of the resultant 6', 7-bis(benzoyloxy)-2', 4'-dimethoxy-3'-(3-methyl-2-butenyl)isoflavone (19) gave 6', 7-dihydroxy-2', 4'-dimethoxy-3'-(3-methyl-2-butenyl)-isoflavone (licoricone) (1). Its isomer, 6', 7-dihydroxy-2', 4'-dimethoxy-5'-(3-methyl-2-butenyl)-isoflavone (2), was also synthesized from 7-benzoyloxy-6'-hydroxy- or 6', 7-bis(benzoyloxy)-2', 4'-dimethoxy-5'-(3-methyl-2-butenyl)isoflavone (11 or 20).
