Menetelmä uusien terapeuttisesti käyttökelpoisten N-difenyylialkyylialkoksisubstituoitujen 3-piperidiinikarboksyylihappojohdannaisten valmistamiseksi

Novel N-substituted azaheterocyclic carboxylic acids and esters thereof in which a substituted alkyl chain forms part of the N-substituent, the compounds thus having the general formula I (I) wherein Y is wherein R1 and R2 independently are C3-8 cycloalkyl phenyl or thienyl all of which may be optionally substituted with halogen, trifluoromethyl, C1-16 alkyl or C1-6 alkoxy; s is 1, 2 or 3; x is -CH2-, -O- or -wherein R3 is hydrogen or C1-6-alkyl; r is 2, 3 or 4; R4 and R5 each represents hydrogen or may together represent a bond and R6 is OH or C1-8-alkoxy; and pharmaceutically acceptable acid addition salts are potent inhibitors of GABA uptake from the synaptic cleft.