157559-65-4

Upstream product

• 13431-36-2 4-isopropyl-3-thiosemicarbazide 
• 2114-00-3 2-bromo-1-phenyl-1-propanone 
• 157559-69-8 2,3-dihydro-5-methyl-4-phenyl-3-(propan-2-yl)-2-(propan-2-ylidenehydrazinylidene)-1,3-thiazole 

Relevant academic research and scientific papers

Unexpected ring enlargement of 2-hydrazono-2,3-dihydro-1,3-thiazoles to 1,3,4-thiadiazines

The cyclization of thiosemicarbazide with α-bromoacetophenone can result in the formation of isomeric 1,3,4-thiadiazines and two different thiazoles. We studied the use of 4-methyl- and 4-ethylthiosemicarbazide as dinucleophilic building blocks. In this c

Syntheses and HPLC separation of chiral 1,3,4-thiadiazines and 1,3,4-selenadiazines

The reaction of 4-isopropylthiosemicarbazide and 4-alkyl(aryl)-2-methyl-thiosemicarbazides and -selenosemicarbazides, respectively, with α-halogenketones gives 1,3,4-thiadiazines and 1,3,4-selenadiazines. The titel compounds undergo, in the presence of acids or bases, ring contraction with extrusion of sulphur and selenium, respectively, and formation of pyrazoles. Studies in this work are reported analytical HPLC separations of chiral 1,3,4-thiadiazines and 1,3,4-selenadiazines, respectively, on different chiral stationary phases (CSP). The influence of various charged and uncharged modifiers in the mobile phase on the chromatographic resolution is discussed.