4-[(5-Bromo-2-hydroxy-benzyl-idene)amino]-N-(4,6-dimethyl-pyrimidin-2-yl)benzene-sulfonamide-4-bromo-2-[(E)-({4-[(4,6-dimethyl-pyrimidin-2-yl)sulfamo-yl]phen-yl}iminio)meth-yl]phenolate [0.61?(7)/0.39?(7)].

ABSTRACT: The title compound, 0.61C(19)H(17)BrN(4)O(3)S·0.39C(19)H(17)BrN(4)O(3)S, is a Schiff base derived from 5-bromo-salicylaldehyde and 4-amino-N-(4,6-dimethyl-2-pyrimidin-yl)benzene-sulfonamide(sulfamethazine) and is isostructural with its chloro analogue. The geometry of the title mol-ecule points to the enol (OH-C=C-C=N) form as the major tautomer, however two electron-density maxima corresponding to the H atoms of the OH and NH groups, found in the region of a strong intra-molecular N?H?O hydrogen bond, do not allow the elimination of the presence of the zwitterionic (O(-)-C=C-C=NH(+)) form in the crystal. Refinement of the occupancies of these H atoms gave a 0.61?(7):0.39?(7) ratio of the enolic and zwitterionic forms. The two benzene rings within the mol-ecule are nearly coplanar and the central benzene ring forms a dihedral angle of 84.1?(1)° with the pyrimidine fragment. An inter-molecular N-H?O hydrogen bond links mol-ecules into chains extended along the a axis and a C-H?O link is also present. The H atoms of one of the methyl groups are disordered over two sites with an occupancy ratio of 0.72?(7):0.28?(7).

SUBMITTER: Shad HA 

PROVIDER: S-EPMC2968005 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature