Research Article: 4-Hy­droxy-2-methyl-1,1-dioxo-2H-1λ6,2- benzothia­zine-3-carb­oxy­lic acid hemihydrate

Date Published: March 01, 2012

Publisher: International Union of Crystallography

Author(s): Farhana Aman, Waseeq Ahmad Siddiqui, Adnan Ashraf, M. Nawaz Tahir.


In the title compound, C10H9NO5S·0.5H2O, two geometrically different organic mol­ecules are present. The benzene rings and the carboxyl­ate groups are oriented at dihedral angles of 13.44 (4) and 21.15 (18)°. In both mol­ecules, an intra­molecular O—H⋯O hydrogen bond generates an S(6) ring. In the crystal, both moleucles form inversion dimers linked by pairs of O—H⋯O hydrogen bonds to generate R22(8) loops. The dimers are consolidated into chains extending along [100] by bridging O—H⋯O hydrogen bonds from the water mol­ecule. A weak C—H⋯O hydrogen bond also occurs.

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For background to non-steroidal anti-inflammatory drugs, see: Akram et al. (2008 ▶); Foye et al. (1995 ▶); Lombardino et al. (1971 ▶, 1973 ▶); Siddiqui, Ahmad, Siddiqui et al. (2008 ▶); Siddiqui, Ahmad, Tariq et al. (2008 ▶). For a related structure, see: Golič & Leban (1987 ▶). For graph-set notation, see: Bernstein et al. (1995 ▶). For puckering parameters, see: Cremer & Pople (1975 ▶).