Process for preparing (s-(r*,s*)) -beta -(((1-(1-oxo-3- (4-piperidinyl) propyl) -3-piperidinyl) carbonyl) amino) -3- pyridinepropanoic acid and derivatives

摘要

A process for preparing a compound of formula I wherein R1 and R2 are independently selected from the group consisting of hydrogen, lower alkyl and halogen