SYNTHESIS OF GAL-BETA-1-4GLCNAC-BETA- AND GAL-BETA-1-3GALNAC-ALPHA-O-L-SERINE DERIVATIVES EMPLOYING GLYCOSIDASES

A new approach for the highly specific preparation of L-serine conjuga tes of lactosamine and Ga1 beta 1-3GalNAc is described. Thus, the L se rine derivative of lactosamine Ga1 beta 1-4GlcNAc beta-O-(N-Z)-Ser-OEt , was obtained from lactose, employing GlcNAc beta-O-(N-Z)-Ser-OEt as acceptor and a yeast beta-galactosidase as catalyst. Ga1 beta 1-3GalNA c alpha-O-(N-Alloc)-Ser-OMe was obtained from lactose, employing GalNA c alpha-O-(N-Alloc)-Ser-OMe as acceptor and beta-galactosidase from bo vine testes as catalyst.