Oxidation of isoeugenol and coniferyl alcohol catalyzed by laccases isolated from Rhus vernicifera Stokes and Pycnoporus coccineus

Laccases isolated from Rhus vernicifera Stokes (tree) and Pycnoporus coccin eus (fungus) catalyzed the oxidation of isoeugenol (1) and coniferyl alcoho l (5) in acetone-water (1:1, v/v). These oxidations follow a first order ra te law. In general, the rates of Pycnoporus laccase-catalyzed oxidation of 1 and 5 are approximately three and seven times faster than the correspondi ng rates of Rhus laccase-catdyzed oxidation, respectively. Thus, synthesis for 2-(4-hydroxyphenyl)coumaran type compounds, such as dehydrodiconiferyl alcohol, can be accomplished by Rhus laccase-catalyzed dehydrogenative poly merization of the corresponding 1-(4-hydroxyphenyl)-1-propene derivatives. The reaction proceeds under very mild reaction conditions. The resulting re action mixtures are chromatographed on a silica gel column to isolate the p roducts in approximately 30-40% yield. (C) 2000 Elsevier Science B.V. All r ights reserved.