Synthesis of alpha and beta-glycopyranosyl-serine derivatives by enzymic transglycosylation.

ABSTRACT

The transglycosylation from raffinose and lactose to Aloc-Ser-OMe is catalyzed respectively by alpha and beta galactosidases. Transglycosylation from cellobiose has been achieved with beta-glucosidase. The simplicity of the enzymatic synthesis, the stereospecificity of the condensations in one-pot reactions and the ease of purification give the method value for large scale preparation of beta-linked derivatives. The protective groups of the serine residue can be cleaved under mild conditions the ester group has been removed quantitatively by papain catalyzed hydrolysis and the Aloc group by a Pd (0) hydrostannolytic cleavage.