Synthesis, pharmacology and therapeutic potential of 10-methoxypyrazino[1,2-a]indoles, partial agonists at the 5HT(2C) receptor

A series of new 10-methoxypyrazino[1,2-a]indoles has been prepared and shown to be 5HT(2C) receptor ligands. The studied compounds 10a-j were found to act as partial agonists at the 5HT(2C) receptor, binding with high affinity and moderate selectivity versus 5HT(1A) and 5HT(2A) receptors, but inducing only a submaximal increase in phosphoinositol formation. Compound 10j was demonstrated to be active in animal models of obsessive-compulsive disorder, depression and panic anxiety.