Synthesis of 2‐(2′,3′‐dihydroxypropyl)‐5‐amino‐2 H ‐1,2,4‐thiadiazol‐3‐one and 3‐(2′,3′‐dihydroxypropyl)‐5‐amino‐3 H ‐1,3,4‐thiadiazol‐2‐one

The synthesis of two new acyclic nucleoside analogs, 2‐(2′,3′‐dihydroxypropyl)‐5‐amino‐2 H ‐1,2,4‐thiadiazol‐3‐one (1) and 3‐(2′,3′‐dihydroxypropyl)‐5‐amino‐3 H ‐1,3,4‐thiadiazol‐2‐one (2), is reported. The first compound, 1, was obtained by reaction of 3‐chloro‐1,2‐propanediol with the sodium salt of 5‐amino‐2 H ‐1,2,4‐thiadiazol‐3‐one (3) in anhydrous dimethylformamide. Similarly, 5‐amino‐3 H ‐1,3,4‐thiadiazol‐2‐one (4) reacted with 3‐chloro‐1,2‐propanediol to give 2. The thiadiazole 4 was prepared by condensation‐cyclization of hydrazothiodicarbonamide (9).