Arif I. Ismiyev

(Z)-Ethyl 2-benzyl-idene-3-oxobutano-ate.

The title molecule, C13H14O3, adopts a Z conformation about the C=C double bond. In the crystal, weak intermolecular C—H⋯O hydrogen bonds with phenyl –CH atoms functioning as donors and the carbonyl O atom of an ester group as acceptor are observed.

rac-5-Acetyl-6-hy­droxy-3,6-dimethyl-4-phenyl-2H-4,5,6,7-tetra­hydro­indazol-1-ium chloride

The structure of the title compound, C17H21N2O2 +·Cl−, is of interest with respect to its biological activity. The title compound comprises an organic cation and a chloride anion in the asymmetric unit. The positive charge is localized in a pyrazole moiety forming a pyrazolium cation. The structure displays intermolecular O—H⋯Cl and N—H⋯Cl hydrogen bonding.

rac-Diethyl 9-hy­droxy-9-methyl-7-phenyl-1,4-diaza­spiro­[4.5]decane-6,8-dicarboxyl­ate

The title molecule, C21H30N2O5, is chiral with four stereogenic centres. The crystal is a racemate and consists of enantiomeric pairs with the relative configuration rac-(6S*,7R*,8R*,9S*). The ethyl fragment of the ethoxycarbonyl group at position 6 is disordered in a 0.46 (3):0.54 (3) ratio. The crystal structure features intermolecular N—H⋯O. Intramolecular O—H⋯N and N—H⋯O hydrogen bonds also occur.

Poly[(μ(3)-rac-5-eth-oxy-carbonyl-6-hy-droxy-6-methyl-4-phenyl-4,5,6,7-tetra-hydro-benzo[c]isoxazol-3-olato)potassium].

The title compound, [K(C17H18NO5)]n, reveals the relative configuration (4R*,5S*,6R*) whereas its crystals are racemic. The cyclohexane ring adopts a half-chair conformation and the isoxazole ring has an envelope conformation. The ethyl fragment of the ethoxycarbonyl group at position 5 is disordered in a 0.547 (7):0.453 (7) ratio. The K+ ion is surrounded by five O atoms from three ligands at distances ranging from 2.606 (2) to 3.028 (2) Å, generating a three-dimensional network. The crystal packing displays intermolecular O—H⋯N and O—H⋯O hydrogen bonds in which the hydroxy group acts as a double proton donor.

rac-Diethyl 6-hy-droxy-4-[(2-hy-droxy-eth-yl)amino]-6-methyl-2-phenyl-cyclo-hex-3-ene-1,3-dicarboxyl-ate.

The title compound, C21H29NO6, is chiral with three stereogenic centres. The crystal is a racemate and consists of enantiomeric pairs with the relative configuration rac-(2R*,3S*,4R*). The ethyl fragment of the ethoxycarbonyl group at position 1 is disordered in a 0.60:0.40 ratio. The crystal packing displays intermolecular O—H⋯O hydrogen bonding. An intramolecular N—H⋯O hydrogen bond also occurs.

Ethyl 3,6-dihy­droxy-6-methyl-4-phenyl-4,5,6,7-tetra­hydro-1H-indazole-5-carboxyl­ate monohydrate

In the title compound, C17H20N2O4·H2O, the cyclohexene ring adopts a half-chair conformation while the indazole ring is essentially planar [maximum deviation = 0.0192 (12) Å]. In the crystal, pairs of intermolecular O—H⋯N hydrogen bonds link the molecules into dimers lying about inversion centers and intramolecular O—H⋯O hydrogen bonds result in six-membered rings. The dimers are further connected by N—H⋯O and O—H⋯O hydrogen bonds.

rac-Ethyl 6-hy-droxy-6-methyl-3-oxo-4-phenyl-1,3,4,5,6,7-hexa-hydro-benzo[c][1,2]oxazole-5-carboxyl-ate.

In the title compound, C17H19NO5, the cyclohexene ring is in a half-chair conformation and the isoxazole ring in an envelope conformation with the N atom as the flap. The C atoms in the 4- and 6-positions are of the same absolute configuration, whereas the C atom in the 5-position is of the opposite configuration, i.e. (4S*,5R*,6S*). The methyl fragment of the ethoxycarbonyl group at position 5 is disordered over two sets of sites in a 0.60:0.40 ratio. The crystal packing displays intermolecular N—H⋯O and O—H⋯O hydrogen bonds.

Crystal structure of phenylhydrazine with diacetyl substituted ketol of the cyclohexane series

The reaction of 2,4-diacetyl-5-hydroxy-5-methyl-3-phenylcyclohexanone-1 with phenylhydrazine is conducted, and the crystal structures of its products, 1-(6-hydroxy-3,6-dimethyl)-2,4-diphenyl-4,5,6,7-tetrahydro-2H-indazol-5-yl)ethane-1-one and 1-(2-hydroxy-2-methyl-6-phenyl-4-(2-phenylhydrazono)-5-(1-(2-henylhydrazono)ethyl)cyclohexyl)ethane-1-one, are determined by single crystal XRD.

Crystal structure of diethyl-5-(2-(1-(4-bromophenyl)ethylidene)hydrazinyl)-3-methyl-1,2-dihydro-[1,1′-diphenyl]-2,6-dicarboxylate

The reaction of diethyl-5-methyl-3-oxo-1,2,3,6-tetrahydro-[1,1′-diphenyl]-2,6-dicarboxylate with (1-(4-bromophenyl)ethylidene)hydrazine is conducted, and the crystal structure of the product of this reaction (diethyl-5-(2-(1-(4-bromophenyl)ethylidene)hydrazinyl)-3-methyl-1,2-dihydro-[1,1′-diphenyl]-2,6-dicarboxylate) is determined by single crystal X-ray diffraction. The conformation of the cyclohexadiene ring in the form of a strongly distorted half-chair is determined based on the X-ray diffraction data. The presence of the intramolecular hydrogen bond of the N–H…O=C type is noted.

rac-5-Acetyl-6-hy­droxy-3,6-dimethyl-4-phenyl-4,5,6,7-tetra­hydro-2H-indazole

The title compound, C17H20N2O2, is chiral but crystallizes in a centrosymmetric space group as a racemate, the relative configuration at the stereogenic centres being 2S*,3R*,4S*. The cyclohexane ring adopts a half-chair conformation while the pyrazole ring has an envelope conformation. The crystal packing displays intermolecular O—H⋯N and N—H⋯O hydrogen bonding.