4-substd-3-chloro-1 2 5 thiadiazoles

摘要

Thiadiazoles of formula (I):- where R = 1. alkyl or alkoxyalkyl, are intermediates e.g. for therapeutically active sulphnamides. Cpds. (I) are prepd. by reaction of cyano-N-chloroforimido alkyl ester(II) with sulphur in a polar aprotic solvent, e.g. DMF, DMA, or hexamethylphosphoric triamide, below 120 degrees (pref. 40-80 degrees).