Enzyme-Mediated Regioprotection-Deprotection of Hydroxyl Groups in (+)-Catechin

Several mono- and polyacetates of (+)-catechin [(2R,3S)-2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-3,5,7-tri ol] have been synthesized by biocatalyzed reactions starting from (+)-catechin or (+)-catechin pentaacetate. In particular, 5-O-acetylcatechin and 7-O-acetylcatechin have been obtained by reaction of catechin with vinyl acetate in the presence of supported Pseudomonas cepacia lipase, while alcoholysis of catechin pentaacetate with 1-butanol catalyzed by the same enzyme yielded 3,3',4',5-O-tetraacetylcatechin and 3,3',4'-O-triacetylcatechin and, under different experimental conditions, 3-O-acetylcatechin.