The butyrates and acetates of heterocyclic alcohols like 3 - hydroxy t
etrahydrofuran and - pyran, 3- and 4 - chromanol as well as the corres
ponding sulfur heterocycles were hydrolyzed using lipase from Candida
rugosa (CRL) and from Pseudomonas cepacia. (PCL). Poor to excellent en
antioselectivities were obtained depending on the structure of the sub
strates. An electrostatic amendment to the steric substrate model for
PCL is proposed.