ChemInform Abstract: 4-Acyl-2-acylamino-4,5-dihydro-1,3,4-thiadiazoles by Acylation of Thiosemicarbazones.
Abstract
Thiosemicarbazones, such as (I), react with acid anhydrides, (II) (in excess), to give the corresponding title compounds of type (IV) [the thiosemicarbazones, formed from thiosemicarbazide and the corresponding carbonyl compounds, maybe used without isolation.
ChemInform Abstract
Thiosemicarbazones, such as (I), react with acid anhydrides, (II) (in excess), to give the corresponding title compounds of type (IV) [the thiosemicarbazones, formed from thiosemicarbazide and the corresponding carbonyl compounds, maybe used without isolation. The acid anhydrides can be replaced by acyl halides: pre-paration of(IVe)]. In some cases the intermediates (III) are isolated, e.g. (IIIe). Fur-ther acylation of the initially formed 2-amino-dihydrothiadiazole (not isolated)with a second acyl halide gives compounds which are differently acylated at thering N and the amino N, such as (VI) via (IIIe).
