83389-02-0

Upstream product

• 16074-94-5 1-(4-methoxy-phenyl)-1,2-dihydro-benzo[d][1,3]thiazine-4-thione 
• 83388-87-8 hydrazono-4 (methoxy-4 phenyl)-1 dihydro-1,4 2H-benzothiazine-3,1 

Relevant academic research and scientific papers

COMPOSES SULFURES HETEROCYCLIQUES. XCVI. REACTION DE L'HYDRAZINE SUR LES DIHYDRO-1,2 BENZOTHIAZINE-3,1 THIONES-4

1-Alkyl-1,2-dihydro-3,1-benzothiazine-4-thiones 1, when reacting with hydrazine, give with a good yield a 1-alkyl-3-amino-2,3-dihydro-1H-quinazoline-4-thione-2, often together with a derivative of 1,3,4-thiadiazole-3. With 1-aryl-1,2-dihydro-3,1-benzothiazine-4-thiones, the main product of the reaction with hydrazine appears to be a 1-aryl-4-hydrazono-1,4-dihydro-2H-3,1-benzothiazine 4, sometimes with some amount of 3.On the contrary, when reacting with hydrazine, 1-alkyl (or 1-aryl)-1,2-dihydro-3,1-benzothiazin-4-ones lead to a 2-alkylamino (or arylamino)-benzohydrazide 5. By thermolysis 4 isomerizes into 2 which is accompanied by derivatives (3 and 7) of 1,3,4-thiadiazole.The structures of compounds 2, 4 and 7 have been studied by NMR and UV spectrometry.