Dimethyl 2,6-dimethyl-4-{3-[4-(methylsulfanyl)phenyl]-1H-pyrazol-4-yl}-1,4-dihydropyridine-3,5-dicarboxylate monohydrate

In the title compound, C21H23N3O4S·H2O, the methylsulfanyl group is disordered over two sets of sites with site-occupancy factors of 0.631 (11) and 0.369 (11). The dihydropyridine ring adopts an E 4 conformation. In the crystal, classical O—H⋯N, O—H⋯O and N—H⋯O hydrogen bonds, as well as C—H⋯O and C—H⋯S contacts, connect the molecules into a three-dimensional network.

In the title compound, C 21 H 23 N 3 O 4 SÁH 2 O, the methylsulfanyl group is disordered over two sets of sites with site-occupancy factors of 0.631 (11) and 0.369 (11). The dihydropyridine ring adopts an E 4 conformation. In the crystal, classical O-HÁ Á ÁN, O-HÁ Á ÁO and N-HÁ Á ÁO hydrogen bonds, as well as C-HÁ Á ÁO and C-HÁ Á ÁS contacts, connect the molecules into a three-dimensional network.
The compound is the hydrate of a mixed pyrazole-1,4-dihydropyridine compound. The thiomethyl group is disordered over two positions with site occupancy factors of 0.631 (11) and 0.369 (11). According to a puckering analysis (Cremer & Pople, 1975), the dihydropyridine ring adopts an E 4 conformation with the flap atom on C31 (E C31 ). The least-squares planes defined by the carbon atoms of the phenyl group and the intracyclic atoms of the pyrazole ring enclose an angle of 48.42 (8) °. At the same time, the aforementioned planes intersect with the least-squares plane defined by the atoms of the 1,4-dihydropyridine ring at angles of 45.18 (7) ° and 86.12 (7) °, respectively.
In the crystal, classical hydrogen bonds of the O-H···N, O-H···O and N-H..O type can be observed that are supported by all nitrogen-and oxygen-bound hydrogen atoms. The bifurcated C H···O contact may influence the eclipsed ester substituent conformation with respect to this group. Furthermore, an intermolecular C-H···S contact is present falling short by more than 0.2 Å of the sum of van-der-Waals radii of the corresponding atoms. These contacts connect the entities in the crystal structure to a three-dimensional network. In terms of graph-set analysis (Etter et al., 1990;Bernstein et al., 1995), the descriptor for these contacts is S(5)S(5)DDDC 1 1 (8)C 1 1 (9) on the unary level. The C 1 1 (9) descriptor detailing the intermolecular C-H···S contacts is shown in Figure 2. Metrical parameters as well as information about the symmetry of these contacts are summarized in Table 1. The shortest intercentroid distance between two aromatic systems was measured at 5.2965 (8) Å and is apparent between the pyrazole and the phenyl moiety in two neighbouring molecules.

Refinement
Carbon-bound H atoms were placed in calculated positions (C-H 0.95 Å for aromatic carbon atoms and C-H 1.00 Å for the methine group) and were included in the refinement in the riding model approximation, with U(H) set to 1.2U eq (C). The H atoms of the methyl groups were allowed to rotate with a fixed angle around the C-C bond to best fit the experimental electron density (HFIX 137 in the SHELX program suite (Sheldrick, 2008), with U(H) set to 1.5U eq (C).
All nitrogen-and oxygen-bound H atoms were located on a difference Fourier map and refined freely.

Figure 1
The molecular structure of the title compound, with atom labels and anisotropic displacement ellipsoids (drawn at 50% probability level). For clarity, only the major component of the split model is depicted.