Highly potent growth hormone secretagogues.

During an effort to search for more potent growth hormone secretagogues, we discovered a class of compounds of which the best compound 8 was 7-fold more active in vitro than the best compound in the series we revealed before [Tata, J. R.; Lu, Z.

Substituted bridged phenyl piperidines: orally active growth hormone secretagogues.

A new series of growth hormone secretagogues have been discovered. The best compound, 26j, shows excellent ability to release growth hormone both in vitro and in vivo. The synthesis and biological activity of these compounds are discussed.