Synthesis and properties of the sulfonyl analogs of 4(5)-aminoimidazole-5(4)-carboxamide, 4(5)-(formylamino)imidazole-5(4)-carboxamide, guanine, and xanthine

Abstract
Reduction of 4(5)-nitroimidazole-5(4)-sulfonamide afforded the sulfonamide analog of 4(5)-aminoimidazole-5-(4)-carboxamide (AICA). This was formylated to afford the sulfonamide analog of formyl-AICA and was ring closed to the unsubstituted 6-sulfonyl analog of guanine, 3-aminoimidazo[4,5-e]-1,2,4-thiadiazine 1,1-dioxide. Diazotization of the latter afforded the corresponding 6-sulfonyl analog of xanthine. The imidazole-sulfonamides or the purine 6-sulfonyl analog did not inhibit the growth of L1210 [mouse neoplastic lymphoid tumor] cells in culture nor were they substrates for or significant inhibitors of human hypoxanthine-guanine phosphoribosyltransferase or milk xanthine oxidase.