Studies on the syntheses of heterocyclic compounds. Part CCCLXXXIX. An alternative synthesis of de-ethyldasycarpidone
Abstract
The synthesis of (±)-de-ethyldasycarpidone (V) is described. The key step involves condensation of indolylmagnesium bromide with methyl isonicotinate 1-oxide to afford the pyridylindole (VI). Hydrogenation of the methiodide of the latter over platinum yielded a mixture of stereoisomers of the amino-esters (X). Normal saponification of the compound (Xa) afforded the amino-acid (XI) which was heated with polyphosphoric acid to give de-ethyldasycarpidone (V).