Synthesis and analgesic activity of 1-(N-methylanilinoethyl)indoles

The synthesis of two series of 1-(N-methylanilinoethyl)indoles is reported. The first arises from the N-alkylation of indole-3-acetic acid or its methylester, while the second was prepared by means of the Witting reaction on the appropriate aldehyde. The compounds were tested in mice (hot plate test and phenyl-p-benzoquinone induced writhing test) for their analgesic activity. None of the compounds was significantly active in the hot plate test. However, N-methylanilinoethyl 1-(N-methylanilinoethyl)-3-indolylacetate (7) was the most active one in the phenyl-p-benzoquinone induced writhing test, which indicates that 7 has a peripheral analgesic effect.