121006-80-2Relevant articles and documents
Heterocyclic systems containing bridgehead nitrogen atom : Part LXXII - Reaction of 5H-2,3-dihydro-1,2,4-triazinoindole-3-thiones with phenacyl bromide, 1,2-dibromomethane and chloroacetic acid
Pal, Ram,Jain, Kiran,Gupta, G D,Handa, R N,Pujari, H K
, p. 1098 - 1103 (2007/10/02)
8-Bromo-5H-dihydro-1,2,4-triazinoindole-3-thione (III), obtained by the reaction of 5-bromoisatin (I) with thiosemicarbazide followed by cyclization of the intermediate 5-bromoisatin-3-thiosemicarbazone (II) with alkali, on condensation with phenacyl bromide gives 8-bromo-3-phenacylthio-5H-1,2,4-triazinoindole (IV).The ketone IV on polyphosphoric acid-catalyzed cyclization furnishes 7-bromo-3-phenylthiazolotriazinoindole (Va) and not 7-bromo-1-phenylthiazolotriazinoindole (VIIa) which has been obtained through unequivocal synthesis.The reaction of III with 1,2-dibromoethane, on the other hand, yields7-bromo-1,2-dihydrothiazolotriazinoindole (VIII), identical with the authentic compound obtained by the reaction II with 1,2-dibromoethane. 5H-6-Methyl-1,2,4-triazinoindole-3-thiolacetic acid (XI), obtained by the reacvtion of 5H-2,3-dihydro-6-methyl-1,2,4-triazinoindole-3-thione (X) with chloroacetic acid, on cyclization with acetc anhydride in the presence or absence of pyridine gave 2-acetyl-3-hydroxy-9-methylthiazolotriazinoindole (XIII).All structures have been established by IR, 1H NMR and mass spectral data.