Synthesis and biological activities of spiroheterocyclic growth hormone secretagogues

The synthesis and biological activities of a series of spiroheterocyclic gr owth hormone secretagogues are reported. Modification of the spiroindane pa rt-structure of the prototypal secretagogue L-162,752 revealed that the spi roindane could be replaced with spirobenzodihydrothiophen derivatives to en hance not only in vitro potency but also oral activity. In this study non-a romatic D-2-amino-4-cyclohexylbutanoic analogs (8a-8d) were also identified to be active secretagogues, (C) 1999 Elsevier Science Ltd. All rights rese rved.