Acta Cryst. (2005). E61, o4107-o4109  [ doi:10.1107/S1600536805036615 ]

Hydrogen-bonding patterns in trimethoprim tetrafluoroborate

M. Hemamalini, P. T. Muthiah and D. E. Lynch

Abstract: In the title compound [systematic name: 2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidinium tetrafluoroborate], C₁₄H₁₉N₄O₃⁺·BF₄^-, the trimethoprim (TMP) molecule is protonated at one of the pyrimidine N atoms. The protonated N atom and 2-amine group of the TMP cation interact with the tetrafluoroborate anion through a pair of N-HF hydrogen bonds [graph set R₂²(8)]. The inversion-related TMP cations are linked through a pair of N-HN hydrogen bonds. The 2-amine group of one TMP cation and the 4-amine group of another cation are bridged by a methoxy O atom, via N-HO hydrogen bonds.

Online 16 November 2005

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