143100-48-5

Upstream product

• 98-09-9 benzenesulfonyl chloride 
• 79465-82-0 L-(2β,3aα,8aα)-1,2,3,3a,8,8a-hexahydro-1,2-dimethoxycarbonylpyrrolo<2,3-b>indole 
• 79631-04-2 N_α-methoxycarbonyl-D-tryptophan methyl ester 
• 136057-11-9 dimethyl (2S,3aR,8aS)-8-benzenesulphonyl-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]indole-1,2-dicarboxylate 
• 141870-92-0 dimethyl (2S,3aR,8aS)-2-methyl-8-phenylsulfonyl-1,2,3,3a,8,8a-hexahydropyrrolo<2,3-b>indole-1,2-dicarboxylate 

Relevant academic research and scientific papers

Conformational analysis of substituted hexahydropyrrolo [2,3-b]indoles and related systems. An unusual example of hindered rotation about sulfonamide S-N bonds. An X-ray crystallographic and NMR study

An indepth comparison of the solution (CDCl3, 1H-NMR) and solid state (X-ray) conformations of the hexahydropyrrolo[2,3-b]indoles 4, 5, and 6 is made. Close parallels with the literature conformations of the aflatoxin furo[2,3-b]benzofuran skeleton and with the conformation of the naturally occurring hexahydropyrrolindole physostigmine are noted. In the solid state the sulfonamide N in 4-6 is non-planar with various degrees of rotation about the S-N bond. In solution, variable temperature 1H-NMR evidence indicates hindered rotation about the N-S bond of the sulfonamide group in 4-6, possibly coupled to inversion of the pyramidal sulfonamide N atom. Reaction of 5 with LDA followed by quenching with methyl iodide resulted in alkylation with clean inversion of configuration.

ENANTIOSPECIFIC SYNTHESIS OF AMINO ACIDS: PREPARATION OF (R)- AND (S)-α-METHYLASPARTIC ACID FROM (S)-TRYPTOPHAN

The enantiospecific synthesis of both antipodes of α-methylaspartic acid from (S)-tryptophan is described with the key steps being alkylation of the hexahydropyrroloindole 4, oxidative degradation of indoles and, for the preparation of the (R)-isomer, Barton reductive decarboxylation.