Piperidinyl-nicotinamides as potent and selective somatostatin receptor subtype 5 antagonists

Nicotinamides of benzyl-substituted 4-aminopiperidines and their seven-membered analogs of generic structure 2 and 2′ have been discovered as potent and selective SST5 antagonists. The activity (Ki) ranges from 2.4 to 436 nM. Most compounds exhibit decent physicochemical properties and follow a clear SAR pattern. Interestingly enough, the receptor is strongly enantiodiscriminating and binds in the amino-azepane-series only the (R)-enantiomer.