The Synthesis of 4-Arylsulfanyl-substituted Kainoid Analogues from trans-4-Hydroxy- -proline

The potent neuroexcitatory activity of kainoid amino acids in the mammalian CNS places new analogues in high demand as tools for neuropharmacological research. A range of 4-arylsulfanyl-substituted kainoids has been synthesised in a parallel fashion via mesylate displacement by a number of aromatic and heteroaromatic thiolates upon (2S,3S,4R)-1-benzoyl-3-tert-butoxycarbonylmethyl-4-methanesulfonyloxy pyrrolidine-2-carboxylic acid methyl ester 8, which is obtainable in eight steps from trans-4-hydroxy- -proline 5.