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Kasthuri Balasubramani

Publications and source records attributed to Kasthuri Balasubramani.

2 recordsLinked to original sources

Hydrogen-bonding and pi-pi interactions in 2-amino-4,6-dimethylpyrimidinium salicylate.

In the crystal structure of the title compound, C6H10N3+.C7H5O3-, the asymmetric unit contains four crystallographically independent 2-amino-4,6-dimethylpyrimidinium and salicylate ions (Z = 8). In each of these, one of the pyrimidine N atoms is protonated, and the carboxylate group of the salicylate ion interacts with the pyrimidine group through a pair of N-H...O hydrogen bonds, forming an R2(2)(8) motif. The pyrimidine cations also form base pairs via a pair of N-H...N hydrogen bonds (involving the amino group and the unprotonated ring N atom), forming another R2(2)(8) motif. Three such R2(2)(8) motifs, fused together, constitute a closed cyclic aggregate, and the linking of these aggregates, arranged in consecutive layers, can be analysed in terms of off-face stacking interactions.

Crystallography, X-Ray↗

Hydrogen-bonding patterns in pyrimethaminium dinitrate.

The title compound, 2,4-diamino-5-(4-chlorophenyl)-6-ethylpyrimidine-1,3-diium dinitrate, C12H15ClN42+.2NO3-, contains two crystallographically independent pyrimethamine (PMN) molecules, which differ in the relative orientations of the pyrimidine and benzene rings and of the ethyl substitutents. In both pyrimethamine molecules, all the pyrimidine N atoms are protonated, unlike most related compounds, in which only one pyrimidine N atom is protonated. The two pyrimethamine moieties are bridged by a variety of N-HO(nitrate) interactions, including some three-centre hydrogen bonds.

Crystallography, X-Ray↗