Hydrolytic enzymatic transformation of advanced synthetic intermediates: on the choice of the organic cosolvent

For enzymatic hydrolyses of advanced synthetic intermediates, the use of an organic cosolvent is often warranted. As a model study, the cosolvent depe ndence (at 10 volume%) of the key enzymatic step in our asymmetric synthesi s of (-)-podophyllotoxin was examined. At high protein concentrations and r t, DMSO and the polyethereal organic cosolvents dioxane, diglyme and trigly me emerged as the best organic cosolvents, in terms of yield, % ee and cata lytic efficiency (V-max/K-m). However, only in 10% triglyme was optimal eff iciency maintained at both lower protein concentration and higher temperatu re. (C) 1999 Elsevier Science Ltd. All rights reserved.