| abstract |
There are provided heterocyclic aromatic compounds useful for stimulating the release or endogenous growth of growth hormone, treating obesity, osteoporosis (bone density improvement), and improving muscle mass and muscle strength. The heterocyclic aromatic compound includes a pharmaceutically acceptable salt thereof and all stereoisomers thereof, and its structure is represented by the following formula (I).n n n <Formula I>n n n n n n n n X a is heteroaryl, preferably (a), (b) or (c), and R 1 , R 1a , R 6 , Y, X b , A, B, Z, R 3 , R 4 , R 4a , R 5 and R 5a are defined herein. |