MODELS OF FOLATE COENZYMES-VII SYNTHESIS AND CARBON TRANSFER REACTIONS OF N5,N10-METHENYL AND N5,N10-METHYLENETETRAHYDROFOLATE MODELS

Article abstract of DOI:10.1016/S0040-4020(01)90903-2

Carboxylate esters react with 1,2-diaminoethanes to yield imidazolines, which upon consecutive reaction with acetic anhydride or tosyl chloride and methyl iodide give imidazolinium salts that serve as models of N⁵,N¹⁰-(CH⁺)-tetrahydrofolate (THF) coenzymes (7a,b and 18a,b).Reduction of the latter salts with sodium borohydride or reaction with anions (R^-) give the corresponding 5,10--THF models.Mono- and bifunctional nucleophiles react with 18a,b to yield carbon-transfer products. 6-Alkylamino-1,3-dimethyluracils react with 1-tosyl-3,4,4-trimethylimidazolidine (the reduction product of 18b), in the presence of acetic acid, to form carbon-transfer products via a mechanism which bears close analogy to the mechanism of action of thymidylate synthetase.