163396-73-4Relevant academic research and scientific papers
Proton-transfer compounds with 4-amino-N-(4,6-dimethylpyrimidin-2-yl) benzenesulfonamide (sulfamethazine): The structures and hydrogen bonding in the salts with 5-nitrosalicylic acid and picric acid
Smith, Graham,Wermuth, Urs D.
, p. 538 - 543 (2013)
The structures of the anhydrous proton-transfer compounds of the sulfa drug sulfamethazine with 5-nitrosalicylic acid and picric acid, namely 2-(4-aminobenzenesulfonamido)-4,6-dimethylpyrimidinium 2-hydroxy-5- nitrobenzoate, C12H15N4O2S +·C7H4NO4 -, (I), and 2-(4-aminobenzenesulfonamido)-4,6-dimethylpyrimidinium 2,4,6- trinitrophenolate, C12H15N4O2S +·C6H2N3O7 -, (II), respectively, have been determined. In the asymmetric unit of (I), there are two independent but conformationally similar cation-anion heterodimer pairs which are formed through duplex intermolecular N+ - H···Ocarboxylate and N - H·· ·Ocarboxylate hydrogen-bond pairs, giving a cyclic motif [graph set R2 2(8)]. These heterodimers form separate and different non-associated substructures through aniline N - H·· ·O hydrogen bonds, one one-dimensional, involving carboxylate O-atom acceptors, the other two-dimensional, involving both carboxylate and hydroxy O-atom acceptors. The overall two-dimensional structure is stabilized by π-π interactions between the pyrimidinium ring and the 5-nitrosalicylate ring in both heterodimers [minimum ring-centroid separation = 3.4580 (8) A]. For picrate (II), the cation-anion interaction involves a slightly asymmetric chelating N - H···O R2 1(6) hydrogen-bonding association with the phenolate O atom, together with peripheral conjoint R 1 2(6) interactions between the same N - H groups and O atoms of the ortho-related nitro groups. An inter-unit amine N - H···Osulfone hydrogen bond gives one-dimensional chains which extend along a and inter-associate through π-π interactions between the pyrimidinium rings [centroid-centroid separation = 3.4752 (9) A]. The two structures reported here now bring to a total of four the crystallographically characterized examples of proton-transfer salts of sulfamethazine with strong organic acids.
