Synthesis and guanase inhibition studies of a novel ring-expanded purine analogue containing a 5:7-fused, planar, aromatic heterocyclic ring system

Article abstract of DOI:10.1016/S0960-894X(98)00672-6

The synthesis of a novel planar, potentially aromatic, ring-expanded xanthine analogue (1), containing the 5:7-fused imidazo[4,5-e][1,4]diazepine ring system, along with guanase inhibition studies are reported. The compound was synthesized in six steps, starting from 1-benzyl-5-nitroimidazole-4- carboxylic acid (2), and was biochemically screened against rabbit liver guanase. Compound 1 is a moderate competitive inhibitor of the enzyme with a K(i) of 2.27 ± 0.66 x 10^-4 M.