Synthesis of α,β-Dehydrotryptophan by reaction of indole with the β-( N-methylamino)dehydroalanine derivative

Abstract

α,β-Dehydrotryptophan 4 is synthesized by a sequence of reactions starting with the corresponding serine derivative 1. This procedure includes substitution reaction between indole and the methylamino group of the β-( N-methylamino)dehydroalanine derivative 3 in acetic acid. The key intermediate 3 is obtained by oxidation of 1 with dimethylsulfoxide activated by p-toluenesulfonyl chloride, followed by reaction of the resulting β- O-tosyldehydroserine 2 with methylamine.