1092115-38-2Relevant academic research and scientific papers
Formation and ring contraction of benzo[f][1,2]thiazepine-1,1-dioxides from and to benzo[e][1,2]thiazine-1,1-dioxides
Khalaj, Ali,Adibpour, Neda
, p. 3662 - 3671 (2008)
Alkoxide-promoted ring expansion of the novel ethyl 2-(6,7-dimethoxy-3-oxo- 3,4-dihydrobenzo[e][1,2]thiazine-1,1-dioxide-2-yl)acetate 3a and analogous 4,4-diethyl derivative 3b and cyclization of methyl 2-[2- (phenylaminocarbonylmethyl sulfamoyl)-4,5-dimethoxyphenyl] acetate 9 to the corresponding new 3-carboxylates and 3-carboxanilide of 7,8-dimethoxy-4-hydroxy- 2,5-dihydrobenzo[f][1,2]thiazepine-1,1-dioxide (5a,b and 10 respectively) is described. Compound 5a was deacylated upon treatment with sodium hydroxide followed by hydrochloric acid to give 7,8-dimethoxy-2,3-dihydrobenzo[f][1,2] thiazepine-1,1-dioxide-4 (5H)-one 8 and its N-ethyl derivative transferred to 6,7-dimethoxy-2-ethyl-3-oxo-3,4-dihydrobenzo[e][1,2]thiazine-1,1-dioxide 7 by the reaction with ethyl methyl ketone in the presence of pyrrolidine. Copyright Taylor & Francis Group, LLC.
