SYNTHESIS OF THE SULFONYL ANALOG OF HYPOXANTHINE, IMIDAZO[4,5-E]-1,2,4-THIADIAZINE 1,1-DIOXIDE

The unsubstituted imidazo[4, 5-e]-l, 2, 4-thiadiazine 1, 1-dioxide was prepared in good yield by reduction of 4(5)-nitroimidazole-5(4)-sulfonamide and immediate ring closure of the unstable aminoimidazole intermediate. Ribosylation of the product by the modified Hilbert-Johnson method afforded a single nucleoside analogue, which is shown to be the 7-(β-D-ribofuranosyl) derivative by comparison of its properties to those of the 5- and 7-methyl derivatives. © 1979, American Chemical Society. All rights reserved.