N-amino>benzoyl>-L-glutamic Acid, a Novel A-Ring Analogue of 2-Desamino-5,8-dideazafolic Acid

Article abstract of DOI:10.1021/jm00092a013

N-<4-<<(3,4-Dihydro-4-oxo-1,2,3-benzotriazin-6yl)methyl>amino>benzoyl>-L-glutamic acid ("2-aza-2-desamino-5,8-dideazafolic acid", ADDF) was synthesized from 2-amino-5-methylbenzamide via a four-step sequence consisting of diazotization, benzylic bromination, condensation with dimethyl N-(4-aminobenzoyl)-L-glutamate, and ester hydrolysis.ADDF was an inhibitor of recombinant mouse thymidylate synthase; inhibition was competitive with 5,10-methylenetetrahydrofolate as variable substrate (K_i=2.3μM).It was a substrate for murine folypolyglutamate synthetase with kinetic characteristics (K_m=28μM) comparable to those of aminopterin, and it inhibited the growth of L1210 cells in culture (IC50=0.052μM).The structural modification of the A-ring embodied in ADDF appears to offer a novel, heterofore unexplored approach to the design of TS inhibitors.