Synthesis and analgesic activity of N,N '-dicarbonyltryptamines

5-Methoxytryptamine and L-tryptophan methyl ester were acylated with maloni c acid, dimethyl malonate, or succinic anhydride to produce the correspondi ng N, N'-dicarbonyl-tryptamine derivatives. The analgesic activity was eval uated by the tail flick test. All of the compounds exhibited desirable anal gesic potency. This result is consistent with that of N-(N-acetyl-L-tryptop hanyl)-5-methoxytryptamine and confirmed that introducing substituted trypt amine into the amide chain of melatonin does enhance analgesic potency.