Synthesis of Heliotramide

Abstract

Both racemates of 4-methoxy-3-hydroxy-2-methylpentane-3-carboxamide are synthesized by reacting isopropylmagnesium chloride with 2-methoxypropionitrile, converting the resulting ketone into the cyanohydrin and hydrolysing to the amide. Comparison with heliotramide shows that the lower melting racemate, m.p. 81-82 °C, is (±)-heliotramide and thus of threo-configuration. The higher melting racemate, m.p. 145-146 °C, is the erythro-amide. Attempts to hydrolyse the amides to the carboxylic acids were unsuccessful. Heliotramide is prepared by heating heliotric acid with urea or by the usual acid chloride-ammonia procedure following protection of the hydroxyl group.