Indole melatonin agonists and antagonists derived by shifting the melatonin side chain from the C-3 to the N-1 or to the C-2 indole position.

This article reviews our efforts in the development of indole melatonin (MLT) agonist and antagonist compounds. Evidence is presented which indicates that high-affinity melatonergic agonists were obtained by shifting the MLT amido side chain from the C-3 to the N-1 indole position. Conversely, by moving the side chain from the C-3 to the C-2 indole position it is possible to produce MLT antagonist compounds.