6-Chloromelatonin
6-Chloromelatonin is a potent melatonin receptor agonist with greater metabolic stability than melatonin. 6-Chloromelatonin compete for [3H]-melatonin and 2-[125I]-iodomelatonin binding to MT1 receptors (pKi=8.9 and 9.1, respectively). 6-Chloromelatonin compete for [3H]-melatonin binding to MT2 receptors (pKi=9.77).