PROCESS FOR THE MANUFACTURE OF ETHANESULFONYL-PIPERIDINE DERIVATIVES

摘要

The present invention relates to a new process for the preparation of compounds of the general formulae (see formula I-a) (see formula I-b) wherein R1- R4 are, independently from each other, hydrogen, halogen, hydroxy, amino, nitro, lower-alkyl-sulfonylamido, or acetamido; R5-R8 are, independently from each other hydrogen, lower-alkyl, halogen, trifluoromethyl or lower-alkoxy; and their pharmaceutically acceptable acid addition salts. The compounds of formulae I-a and I-b are NMDA (N-methyl-D-aspartate)- receptor-subtype selective blockers, which have a key function in modulating neuronal activity and plasticity which makes them key players in mediating processes underlying development of CNS including learning and memory formation and function.