Ethyl 7-chloromethyl-5-(2-chlorophenyl)-7-hydroxy-2-methylsulfanyl-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-a]pyrimidine-6-carboxylate

In the title compound, C16H18Cl2N4O3S, the five-membered ring is almost planar [maximum deviation = 0.011 (3) Å] and the six-membered ring adopts an envelope conformation. In the crystal structure, N—H⋯N, O—H⋯N and C—H⋯O interactions link molecules into a three-dimensional network.

In the title compound, C 16 H 18 Cl 2 N 4 O 3 S, the five-membered ring is almost planar [maximum deviation = 0.011 (3) Å ] and the six-membered ring adopts an envelope conformation. In the crystal structure, N-HÁ Á ÁN, O-HÁ Á ÁN and C-HÁ Á ÁO interactions link molecules into a three-dimensional network.
In the crystal structure, weak N-H···N, O-H···N and C-H···O interactions link the molecules into a three-dimensional network (Fig. 2).

Refinement
The N-and O-bound H atoms were located in a difference map and freely refined with fixed isotropic displacement parameters. All other H atoms were positioned geometrically, with C-H = 0.93, 0.97 and 0.96 Å for aromatic, methylene and methyl H, respectively, and constrained to ride on their parent atoms, with U iso (H) = 1.2U eq (C) or 1.5U eq (methyl C). Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at the 50% probability level.

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.