The preparation of 2H‐1,2,3‐benzothiadiazine‐1,1‐dioxides, 11H‐11a‐dihydrobenzimidazo[1,2‐b] [1,2] benzisothiazole‐5,5‐dioxides, 6H‐dibenzo[c,g] [1,2,5] thiadiazocine‐5,5‐dioxides and 5H‐Dibenzo[c,g] [1,2,6] thiadiazocine‐6,6‐dioxides

Abstract

o‐Benzoylbenzenesulfonyl chlorides (I) were prepared conveniently from aminobenzophenones by diazotization followed by reaction with sulphur dioxide in the presence of Cu+, according to the general method of Meerwein. Reaction of the sulfonyl chlorides with hydrazine led to 4‐phenyl‐2H‐1,2,3‐benzothiadiazine‐1,1‐dioxides (II). The latter compounds could be methylated and acetylated readily in the 2‐position. The 2‐methyl derivative (III) could be prepared also by reaction of the sulfonyl chloride (Ia) with methylhydrazine. Catalytic hydrogenation of 6‐chloro‐4‐phenyl‐2H‐1,2,3‐benzothiadiazine‐1,1‐dioxide (IIa) gave the 3,4‐dihydro derivative (V). Reaction of the sulfonyl chlorides (I) with o‐phenylenediamine followed by cyclodehydration led to 11H‐11,11a‐dihydrobenzimidazo[1,2‐b] [1,2]benzisothiazole‐5,5‐dioxides (VII). One of the latter compounds (VIIa) in sodium hydroxide solution in the presence of methyl iodide or benzyl chloride was transformed into 6‐methyl‐ and 6‐benzyl‐5H‐dibenzo[c,g] [1,2,6]thiadiazocine‐5,5‐dioxides (VIII), respectively. 5H‐Dibenzo[c,g] [1,2,6] thiadiazocine‐6,6‐dioxides (XIV) were prepared also by cyclodehydration of 2‐amino‐2′‐benzoylbenzenesulfonanilides (XIII).

Rational Design and Synthesis of Diverse Pyrimidine Molecules Bearing Sulfonamide Moiety as Novel ERK Inhibitors

“…Through this work, we illustrate a proficient methodology for the production of several new heterocycles, containing a sulfonamide moiety, exploiting 1-(4-((4-methylpiperidin-1-yl)sulfonyl)phenyl)ethan-1-one ( 3 ) as a precursor. The aforementioned derivative was generated through the reaction of 4-acetylbenzenesulfonyl chloride ( 1 ) [53] with 4-methylpiperidine ( 2 ). The c ondensation of compound 3 with dimethylformamide-dimethylacetal (DMF-DMA) under reflux conditions in dry xylene afforded the corresponding enaminone ( 4 ) while the reaction of 3 with phenylhydrazine in an ethanol/acetic acid solution, delivered the phenylhydrazone derivative ( 5 ).…”