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Synthesis of 3,4‐Dihydro‐2‐methyl‐3‐oxo‐ N ‐aryl‐2 H ‐[1]benzothieno[3,2‐ e 1,2‐thiazine‐4‐carboxamide 1,1‐Dioxides
Author(s) -
Marfat A.,
Chambers R. J.
Publication year - 1988
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570250250
Subject(s) - chemistry , thiazine , methylamine , thiophene , sulfonamide , carboxamide , aryl , acetic acid , ring (chemistry) , medicinal chemistry , stereochemistry , organic chemistry , alkyl
A novel synthesis of the title compounds, representing a new heterocyclic ring system, is described. Chlorosulphonation of 3‐methylbenzo[ b ]thiophene followed by reaction with methylamine gave sulfonamide, 4 . Lithiation of 4 , followed by quenching with carbon dioxide yielded acetic acid, 5 . Cyclodehydration of 5 to benzothienothiazine 6 followed by reaction with aryl isocyanates afforded the desired benzothieno[3,2‐ e ]‐1,2‐thiazine‐4‐carboxamides 1a‐f.