The present study deals with the crystal structures of four organic salts, namely, trimethoprim benzene sulfonate monohydrate 1, trimethoprim sulfanilate monohydrate 2, trimethoprim p-toluene sulfonate 3 and trimethoprim 3-carboxy-4-hydroxybenzene sulfonate dihydrate 4. Trimethoprim (TMP) is protonated at one of the ring nitrogens of the pyrimidine ring. Generally, in the TMP carboxylate complexes, the protonated pyrimidine ring is hydrogen-bonded to the carboxylate group forming a cyclic fork-like hydrogen-bonded bimolecular motif. In structures 1-3, the sulfonate group plays the role of the carboxylate anion. In compounds 1 and 2, there is no pairing of the pyrimidine rings because the pairing sites are blocked by water molecules donating hydrogen to the unprotonated ring nitrogen. Two of the cyclic motifs are bridged by the water molecule donating two hydrogen atoms, leading to a hydrogen-bonded supramolecular chain. This chain pairs with another chain running in the opposite direction. These two chains are cross-linked by O-H … O hydrogen bonds. In compound 2, two of the hydrogen atoms of the amino group of the sulfanilate bridge two methoxy oxygen of the two TMP cations via N-H … O hydrogen bonds resulting in a supramolecular zig-zag chain. In compound 3, two inversion related cyclic motifs are paired through a pair of N-H … N hydrogen bonds involving the 4-amino group and the N3 atom of the pyrimidine ring. In addition to the pairing, one of the sulfonate oxygen atoms bridges the 2-amino and 4-amino groups on either side of the paired bases, resulting in a self-complementary DADA (D represents the hydrogen bond donor and A represents hydrogen bond acceptor) array of quadruple hydrogen bonding patterns. In compound 4, one of the water molecules forms a hydrogen-bonded dimer with the inversion-related water molecule. The 3-carboxy-4-hydroxybenzene sulfonate moiety self-assembles into a supramolecular chain along the c axis through O-H … O hydrogen bonds. Two such oppositely running supramolecular chains are connected by dimeric and monomeric water molecules. The variation of supramolecular organization via hydrogen bonding in the four different trimethoprim sulfonate salts has been discussed.
The 3-cyclohexene units adopt envelope conformations in each of the two independent molecules that comprise the asymmetric unit of the title compound, C20H16F2O3. The dihedral angles between the two fluorophenyl rings are 79.7 (2) and 73.7 (2)° in the two molecules. In one of the molecules, two C—H groups of the cyclohexene ring are disordered over two sets of sites in a 0.818 (13):0.182 (13) ratio, the major and minor components corresponding to the two enantiomeric forms of the molecule. Weak intermolecular C—H⋯O interactions help to stabilize the crystal structure.
Key indicatorsSingle-crystal X-ray study T = 273 K Mean (C-C) = 0.004 Å R factor = 0.036 wR factor = 0.106 Data-to-parameter ratio = 12.9For details of how these key indicators were automatically derived from the article, see
Key indicatorsSingle-crystal X-ray study T = 293 K Mean '(C±C) = 0.002 A Ê R factor = 0.045 wR factor = 0.136 Data-to-parameter ratio = 17.1 For details of how these key indicators were automatically derived from the article, see
In the title salt, C36H48N4
2+·2Br−·H2O, the central benzene ring makes dihedral angles of 84.77 (9) and 69.92 (7)° with the adjacent imidazole rings. In the crystal, one of the heptyl groups is disordered over two sets of sites with an occupancy ratio of 0.474 (5):0.526 (5). In the crystal, the cations, anions and water molecules are connected via intermolecular O—H⋯Br, C—H⋯Br and C—H⋯O hydrogen bonds, forming a three-dimensional network.
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