SB-203207 and SB-203208, Two Novel Isoleucyl tRNA Synthetase Inhibitors from a Streptomyces sp.

II. Structure Determination

Abstract

Two novel isoleucyl tRNA synthetase inhibitors, SB-203207 and SB-203208 have been isolated from a Streptomyces sp. and found to be structurally related to altemicidin. Structures of SB-203207 and SB-203208 have been deduced by a combination of spectroscopic techniques, derivatisation, hydrolysis studies and found to be 4-(aminocarbonyl)-7-{[(2-amino-3-methylpentanoyl)aminosulphonyl]acetamido}-2, 4a, 5, 6, 7, 7a-hexahydro-6-hydroxy-2-methyl-1H-2-pyrindine-7-carboxylic acid (1) and 4-(aminocarbonyl)-7-{[(2-amino-3-methyl pentanoyl)-aminosulphonyl]acetamido}-2, 4a, 5, 6, 7, 7a-hexahydro-6-(2-amino-3-phenylbutanoyl oxy)-2-methyl-1H-2-pyrindine-7-carboxylic acid (2), respectively.