Synthesis of 1-(oxiran-2-ylmethyl)-1<Emphasis Type="Italic">H</Emphasis>-indole-3-carbaldehyde and its reaction with active methylene compounds

Treatment of indole-3-carbaldehyde with epichlorohydrin gave 1-(oxiran-2-ylmethyl)-1H-indole-3-carb-aldehyde, reaction of which with 1,3-dimethylbarbituric acid or malononitrile gave crotonic condensation products with retention of the oxirane ring. The structure of the reaction products with aroylglycines depends on the conditions. In acetic anhydride a simultaneous formation of an oxazolone ring and bisacylation of the oxirane fragment occurs; the use of ethyl chloroformate in the presence of triethylamine allows to carry out only the heterocyclization process. When treated with the cyclic amines (N-methylpiperazine or morpholine) opening of the oxazolone ring in the products occurs with formation of the corresponding amides.