B.P. Reddy

3,3,6,6-Tetra-methyl-9-phenyl-3,4,5,6-tetra-hydro-9H-xanthene-1,8(2H,7H)-dione.

In the title compound, C23H26O3, the three six-membered rings of the xanthene system are non-planar, having total puckering amplitudes, Q T, of 0.443 (2), 0.202 (2) and 0.449 (2) Å. The central ring adopts a boat conformation and the outer rings adopt sofa conformations. The crystal structure is stabilized by van der Waals interactions.

3-Acetyl-6-chloro-2-methyl-4-phenyl-quinolinium hydrogen sulfate.

In the title salt, C18H15ClNO+·HSO4 −, the quinolinium ring system is approximately planar, with a maximum deviation of 0.028 (2) Å, and forms a dihedral angle of 78.43 (4)° with the attached phenyl ring. A pair of intermolecular O—H⋯O hydrogen bonds links two hydrogen sulfate anions into a dimer, generating a R 2 2(8) ring motif. Intermolecular N—H⋯O hydrogen bonds and C—H⋯O contacts link the ions into a three-dimensional network. The structure is further stabilized by C—H⋯π interactions

Diisobutyl 4-(3-eth­oxy-4-hy­droxy­phen­yl)-2,6-dimethyl-1,4-dihydro­pyridine-3,5-dicarboxyl­ate

The asymmetric unit of the title compound, C25H35NO6, contains two independent molecules. In each molecule, the 1,4-dihydropyridine ring adopts a flattened boat conformation. The dihedral angles between the 1,4-dihydropyridine and benzene rings are 87.55 (7) and 87.23 (7)°. In one of these molecules, one of the isobutyl groups is disordered over two sets of sites, with an occupancy ratio of 0.890 (2):0.110 (2). In the crystal, molecules are linked through N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds forming two-dimensional networks parallel to the ab plane. The crystal structure is further stabilized by weak C—H⋯π interactions.

6-Chloro-3-[5-(4-fluoro-phen-yl)-1-phenyl-4,5-dihydro-1H-pyrazol-3-yl]-2-methyl-4-phenyl-quinoline.

In the title compound, C31H23ClFN3, the pyrazole ring forms dihedral angles of 72.75 (7), 18.08 (9) and 86.26 (9)° with the quinoline ring system, the phenyl ring and the fluorophenyl ring, respectively. In the crystal, intermolecular C—H⋯N hydrogen bonds link the molecules into chains propagating along the c axis. The crystal structure is further stabilized by C—H⋯π interactions.

Diethyl 2,6-dimethyl-4-p-tolyl-1,4-dihydro­pyridine-3,5-dicarboxyl­ate

In the title compound, C20H25NO4, the 1,4-dihydropyridine ring adopts a flattened-boat conformation and forms a dihedral angle of 89.77 (8)° with the benzene ring. Intermolecular N—H⋯O hydrogen bonds result in the formation of extended chains parallel to the b axis.

1,1′-[4-(4-Methoxy­phen­yl)-2,6-dimethyl-1,4-dihydro­pyridine-3,5-di­yl]diethanone

In the title compound, C18H21NO3, which belongs to the family of calcium channel blockers, the dihydropyridine ring assumes a flattened boat conformation. The two carbonyl units adopt a synperiplanar conformation with respect to the double bonds in the dihydropyridine ring. The methoxyphenyl ring is almost perpendicular to the prydine ring [dihedral angle = 89.01 (7)°]. In the crystal, the molecules are connected by intermolecular N—H⋯O hydrogen bonds.

(E)-N-Benzyl-idene-4H-1,2,4-triazol-4-amine.

The title compound, C9H8N4, crystallizes with three independent molecules (A, B and C) per asymmetric unit. The independent molecules differ slightly in their conformations, the dihedral angles between the triazole and phenyl rings in molecules A, B and C being 4.8 (2), 9.7 (2) and 7.2 (2)°, respectively. In the crystal, the independent molecules are linked into a trimer by C—H⋯N hydrogen bonds.

Dimethyl 4-(3,4-dimethoxy­phen­yl)-2,6-dimethyl-1,4-dihydro­pyridine-3,5-dicarboxyl­ate

In the title compound, C19H23NO6, the 1,4-dihydropyridine ring is twisted slightly from planarity, with a maximum deviation of 0.101 (1) Å, and adopts a very flattened boat conformation. The dihedral angle formed between the plane through the four C atoms of the 1,4-dihydropyridine ring and the benzene ring is 84.67 (7)°. In the crystal structure, intermolecular N—H⋯O and C—H⋯O hydrogen bonds link the molecules into a three-dimensional network.

Diethyl 4-(4-ethoxy-phen-yl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxyl-ate.

In the title compound, C21H27NO5, the dihydropyridine ring adopts a boat conformation. The ethoxyphenyl ring is oriented approximately perpendicular to the planar part of the dihydropyridine ring, making a dihedral angle of 89.45 (6)°. An intramolecular C—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal structure, neighbouring molecules are linked into chains along the a axis by N—H⋯O hydrogen bonds and the chains are interconnected into two-dimensional networks parallel to the ab plane by C—H⋯O hydrogen bonds. The structure is further stabilized by weak C—H⋯π interactions.

Diethyl 2,6-dihy-droxy-4-(3-nitro-phen-yl)-2,6-bis-(trifluoro-meth-yl)piperidine-3,5-dicarboxyl-ate.

In the title compound, C19H20F6N2O8, the ethoxy and ethyl groups are disordered over two sets of sites, with occupancy ratios of 0.212 (18):0.788 (18) and 0.746 (6):0.254 (6), respectively. The piperidine ring adopts a chair conformation. In the molecule, intramolecular O—H⋯O hydrogen bonds form two S(6) ring motifs. In the crystal, molecules are linked via O—H⋯O and C—H⋯O hydrogen bonds, forming dimers.