Synthesis and crystal structures of 2-amino-3-cyano-4-(2-chlorophenyl)-1,4-dihydro-2H-pyrano[3, 2-h]quinoline and 2-amino-3-cyano-4-(2-chlorophenyl)-8-(2-chlorobenzylidene)-1,4,5,6,7,8-hexahydrobenzo[b]pyran

The title compounds 2-amino-3-cyano-4-(2-chlorophenyl)-1,4-dihydro-2H-pyrano[3, 2-h]quinoline 1 (C₁₉H₁₂ClN₃O, M _r = 333.77) and 2-amino-3-cyano-4-(2-chlorophenyl)-8-(2-chlorobenzylidene)-1,4,5,6,7,8-hexahydrobenzo[b]pyran 2 were synthesized and crystallized. The crystals of compound 1 are triclinic, space group P-1, a = 7.488(2), b = 9.127(3), c = 12.252(3) Å, = 73.58(2), = 78.38(2)°, = 75.39(2), Z = 2, V = 769.5(4) ų; The compound 2 crystallizes in space group P2₁/n, with cell parameters a = 13.582(2), b = 8.974(1), c = 16.960(2) Å, = 103.34(1)° and D _calc = 1.352 g/cm^–3 for Z = 4. X-ray analysis reveals that atoms C(1)—C(5) and O form a pyran ring in compound 1, which adopts half-chair conformation. In compound 2 the atoms C(12)—C(16) and O form a pyran ring which adopts boat conformation, another six-membered ring (C(8)—C(13)) adopts a half-chair conformation. In addition, there are intermolecular hydrogen bonds in the crystal structures 1 and 2.     

Synthesis and crystal structures of 5-amino-1-(2-hydroxyethyl)imidazole-4-carboxamide and 5-amino-1-(2-chloroethyl)-4-cyanoimidazole

Both 5-amino-1-(2-hydroxyethyl)imidazole-4-carboxamide (AHIC) and 5-amino-1-(2-chloroethyl)-4-cyanoimidazole (ACCI) have been synthesized and crystallized in the monoclinic space group P2₁/c, Z = 4, with a = 8.420(2), b = 9.759(2), c = 10.583(2) Å, = 111.80(2)° for AHIC and a = 6.139(1), b = 8.522(2), c = 15.156(3) Å, = 96.71(2)° for ACCI. Differences in the molecular geometries of the two compounds are attributed to the differences in the substituents at the 1- and 4-positions of the imidazole ring. The molecular conformation of AHIC is stabilized by intramolecular hydrogen bonding between the 5-amino and the vicinal carboxamide moiety, resulting in an extended planar structural pattern. The presence of the cyano group in the 4-position of ACCI prevents the formation of such an intramolecular hydrogen bond. Both the crystal structures are stabilized by networks of intermolecular hydrogen bonds.     

Molecular and crystal structures of 3-benzoyl-4-hydroxy-4-phenyl-(N-methyl)piperidine and 5-hydroxymethylene-4-phenyl-N-methyl-1,2,5,6-tetrahydropyridine

The crystal structures of two compounds—3-benzoyl-4-hydroxy-4-phenyl-(N-methyl)piperidine (I) [orthorhombic crystals, space group P2₁2₁2₁, Z = 4] and 5-hydroxymethylene-4-phenyl-(N-methyl)-1,2,5,6-tetrahydropyridine (II) [monoclinic crystals, space group P2₁/n, Z = 4]—are determined by X-ray diffraction. In I, the weak intermolecular OH?N hydrogen bonds link the molecules related by the a translation into homochiral chains. In II, the OH?N hydrogen bonds link the molecules into infinite homochiral chains twisting about the crystallographic screw axes 2₁(y). The helices are additionally strengthened by the short CH?O contacts.     

The hydrogen bonding in 2-amino-3-cyano-4-(3-nitrophenyl)-4,6-dihydro-5H-pyrano[3,2-c]quinolin-5-one N,N-dimethylformamide solvate monohydrate

The crystal structure of 2-amino-3-cyano-4,6-dihydro-4-(3-nitrophenyl)-5H-pyrano[3,2-c]quinolin-5-one N,N-dimethylformamide solvate monohydrate is determined by room temperature X-ray diffraction. The title compound 1, C₂₂H₂₁N₅O₆, is triclinic, space group P-1, a=9.109(2) ?, b=11.340(2) ?, c=12.485(2) ?, α=70.02(1)°, β=69.36(1)°, γ=67.32(1)°, Z=2, V=1081.4(4) ?³. It is interesting that a bridge-like hydrogen bond O–H···O is formed between the title compound and solvent molecules of water with molecular ratio of 2:2 building a bi-layer framework. In addition, there are two other types of classical hydrogen bonds N–H···N and N–H···O in the crystal structure.Supplementary material Crystallographic data for the structure reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no. CCDC-275001. Copies of available material can be obtained, free of charge, on application to the Director, CCDC, 12 Union Road, Cambridge CB2 1EZ, UK, (fax: +44-(0) 1223–336033 or e-mail: deposit@ccdc.cam.ac.uk).     

X-ray crystallography of methyl (6-amino-5-cyano-2-methyl-4-(2-nitrophenyl)-4<Emphasis Type="Italic">H</Emphasis>-pyran)-3-carboxylate

The organic carbonitrile namely methyl (6-amino-5-cyano-2-methyl-4-(2-nitrophenyl)-4H-pyran)- 3-carboxylate is synthesized via one-pot multi-component reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst and its crystal structure is determined by X-ray technique. The crystals are monoclinic, sp. gr. C2/c, a = 12.3069(8) Å, b = 9.7023(7) Å, c = 24.812(2) Å, β = 94.862(6)°, Z = 8. The dihedral angle between pyran and phenyl rings is 87.8(1)°; the pyran ring is almost planar The dihedral angle between the mean planes of phenyl ring and nitro group is 44.4(2)°. The crystal structure is stabilized by N?H···N and N?H···O hydrogen bonds. In addition, C?H···π interactions are also observed in the crystal structure.     

Synthesis and crystal structure of 5-amino-4-cyano-1-[(5-methyl-1-t-butyl-4-pyrazolyl)carbonyl]-3-methylthio-1H-pyrazole

The title compound, 5-amino-4-cyano-1-[(5-methyl-1-t-butyl-4-pyrazolyl)carbonyl]-3-methylthio-1H-pyrazole 5, was synthesized by the treatment of 4 (5-methyl-1-t-butylpyrazole-4-carbohydrazide) with 2-cyano-3, 3-dimethylthio-acrylonitrile, and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic, space group P2₁/c with unit cell parameters a = 13.566(4) Å, b = 10.833(3) Å, c = 11.202(3) Å, α = 90°, β = 98.073(5)°, γ = 90°, V = 1629.9(8) ų, Z = 4, D _c = 1.298, M _r = 318.40, μ = 0.210 mm⁻¹, F(000) = 672, R ₁ = 0.0488 and wR ₂ = 0.1250.     

Synthesis and crystal structure of 3,4-trans-4, 5-trans-2-amino-3-cyano-1,3-dimethyloxycarbonyl-4, 5-di(3,4-methyl-enedioxylphenyl) cyclopentene

The 3,4-trans-4,5-trans-2-amino-3-cyano-1,3-dimethyloxycarbonyl-4,5-di-(3,4-methyl-enedioxylphenyl) cyclopentene has been synthesized and characterized by IR, ¹H NMR, Elemental analysis, and X-ray crystallography. It crystallizes in the monoclinic space group P2₁/n, with a = 10.936(3) Å, b = 10.142(3) Å, c = 20.001(4) Å, = 93.81(2)°, and D _calc = 1.390 g cm^–3 for Z = 4. X-ray analysis reveals that the phenyl groups and the alkoxyl carbonyl group are in the equatorial positions. The dihedral angles between the phenyl groups and the central five-membered ring are 73.08° and 62.15°. In addition, there are intermolecular hydrogen bonds in the crystal lattices.     

Molecular and crystal structures of 1R,4S-2-(4-carbomethoxy)benzylidene-n-menthan-3-one

The molecular and crystal structures of chiral 1R,4S-2-(4-carbomethoxy)benzylidene-n-menthan-3-one (I) are determined by X-ray diffraction analysis. Crystals I are orthorhombic; at 20°C: a = 11.961(3) Å, b = 26.453(8) Å, c = 5.400(2) Å, space group P2₁2₁2₁, and Z = 4 (C₁₉H₂₅O₃). In molecule I, the cyclohexanone ring with the axial methyl and isopropyl substituents adopts a chair conformation. It is found that the enone and arylidene fragments of compound I have a substantially nonplanar structure. The shortened intramolecular contacts between atoms of the arylidene grouping and the α fragment of the cyclohexanone ring and their associated distortions of bond angles at the sp ² carbon atoms are the common structural features of 2-arylidene-n-menthan-3-ones irrespective of the stereochemical configuration of the C(4) chiral center.     

The Synthesis and Crystal Determination of 3-Hydroxy-4-(4-methoxyphenyl)-5-(2-nitrophenyl)furan-2(5H)-one

Abstract  

The title compound, C₁₇H₁₃NO₆, was synthesized and structurally characterized by elemental analysis, MS, ¹H NMR and single crystal X-ray diffraction. It crystallizes in monoclinic system space group C 2/c with a = 27.981(6) ?, b = 12.996(3) ?, c = 8.0900(16) ?, β = 91.06(3)°, V = 2941.4(10) ?³, Z = 8, R ₁ = 0.0675, wR ₂ = 0.1626, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with p-methoxybenzene ring and forms a dihedral angle of 87.2(1)° with the nitrobenzene ring. O–H···O Intermolecular hydrogen bonds link pairs of molecules into centrosymmetric dimers, making a graph set motif of R ₂²(10). The dimers are further assembled into a chain of edge-fused R ₄⁴(34) rings running along the [001] direction. The final three-dimensional supramolecular architecture is stabilized by weak π–π interactions.     

Molecular and crystal structures of 1R,4R-cis-2-(4-hydroxybenzylidene)-p-menthan-3-one

The molecular and crystal structures of chiral 1R, 4R-cis-2-(4-hydroxybenzylidene)-p-menthan-3-one (I) are determined by X-ray diffraction analysis. Single crystals of I are orthorhombic, a = 8.997(2) Å, b = 11.314(2) Å, c = 14.847(3) Å, V = 1511.3(5) ų, Z = 4, and space group P2₁2₁2₁. The cyclohexanone ring in molecules of compound I has a chair-type conformation with the axial methyl and equatorial isopropyl groups. The enone and benzylidene groupings are nonplanar. The considerable distortion of bond angles at the sp ² carbon atoms of the benzylidene grouping and the puckering parameters of the cyclohexanone ring in the structure of I are close to those observed for the previously studied compound with the p-methoxy substituent. In the crystal, molecules I are linked by very short intermolecular hydrogen bonds .     

Molecular and crystal structures of 1R,4R-cis-2-(4-phenylbenzylidene)-n-menthan-3-one

The molecular and crystal structures of chiral 1R,4R-cis-2-(4-phenylbenzylidene)-n-menthan-3-one (I) have been determined by X-ray diffraction analysis. Crystals I are monoclinic, a = 6.755(3) Å, b = 9.860(3) Å, c = 14.103(6) Å, β = 98.95(1)°, space group P2₁, Z = 2, and R = 0.035 for 1031 reflections. A chair conformation of the cyclohexanone ring in the molecule is substantially distorted toward a “half-chair” conformation. The enone and benzylidene groupings are virtually planar (the torsion angles are equal to 13.0° and 4.9°, respectively). The benzene rings of the biphenyl fragment are rotated with respect to each other through an angle of 40°–43°. Among the compounds under consideration, the distortion of bond angles at the sp ² carbon atoms of the benzylidene grouping as a criterion for the steric stress of molecules is maximum in structure I.     

Crystal Structure and Molecular Conformational Studies of Allyl 6-Amino-5-cyano-4-(4-fluorophenyl)-2-methyl-4H-pyran-3-carboxylate

Crystallography Reports - The allyl 6-amino-5-cyano-4-(4-fluorophenyl)-2-methyl-4H-pyran-3-carboxylate, C17H15FN2O3, compound adopts a triclinic crystal system with the sp. gr. $$P\bar {1}$$, Z =...     

Molecular and crystal structures of chiral 2-(4-phenylbenzylidene)-3-methyl-6-isopropylcyclohexanone 6-bromo derivative

The molecular and crystal structures of chiral 3R, 6S-2-(4-phenylbenzylidene)-3-methyl-6-bromo-6-isopropylcyclohexanone C₂₃H₂₅BrO (Ia) are determined by X-ray diffraction. Crystals Ia are monoclinic, a = 11.005(4) Å, b = 12.229(4) Å, c = 14.376(5) Å, β = 91.37(1)°, Z = 4, and space group P2₁. The geometric parameters of two crystallographically independent molecules are close to each other in magnitude. The cyclohexanone ring adopts a chair-type conformation with an equatorial isopropyl substituent and an axial orientation of the methyl group and the C-Br bond. The 3,6-alkyl groups are in the cis position with respect to the cyclohexanone ring. It is demonstrated that, in the series of 6-bromo substituted compounds, as in their analogues unsubstituted for bromine in the 6-position, the maximum flattening of the cinnamoyl fragment O=C-C=C-C₆H₄ X is observed in the structure with X = C₆H₅.     

Crystal structure of 3-amino-5-acetyl-4,7-dihydro-6-methyl-4-(2-nitrophenyl)-2-cyanothieno[2,3-b]-pyridine and specific features of its molecular packing in crystal

The molecular and crystal structures of 3-amino-5-acetyl-4,7-dihydro-6-methyl-4-(2-nitrophenyl)-2-cyanothieno[2,3-b]-pyridine is determined by X-ray diffraction. The unit-cell parameters are as follows: a = 14.68(1) Å, b = 8.704(5) Å, c = 25.36(1) Å, V = 3241(6) ų, d _calcd = 1.453 g/cm³, Z = 8(1,1), and space group Pna2₁. Theo-nitrophenyl substituent is synperiplanar relative to the hydrogen atom at the C(4) atom of the heterocycle. Two crystallographically independent reference molecules A and B in the structure can be considered a pair of the enantiomers related by an approximate noncrystallographic center of inversion. The degree of approximation of this pseudocenter is discussed. It is shown that the structure can be described as a combination of two systems of translationally equal layers. The pseudosymmetry of the crystal structure and the possibility of forming a similar molecular packing with a higher crystallographic symmetry are considered.     

Crystal and molecular structures of 2-amino-5-(m-nitrophenyl)-1,3,4-Thiadiazole

2-Amino-5-(m-nitrophenyl)-1,3,4-thiadiazole (C₈H₆N₄O₂S) is studied using IR and ¹H NMR spectroscopy and X-ray diffraction (CAD4 automated diffractometer, λMoK _α, graphite monochromator, 957 unique reflections, Patterson method, R = 0.0326). The crystals are monoclinic, a = 11.832 Å, b = 9.862 Å, c = 8.353 Å, β = 110.40(3)°, V = 913.6(3) ų, d _calcd = 1.212 g cm^?3, μ(MoK _α) = 0.253 mm^?1, Z = 4, and space group P2₁/c. In the crystal, the C₈H₆N₄O₂S molecules form infinite layers parallel to the xz plane. Each layer contains aromatic rings with nitro groups that deviate from the layer plane on either side of the layer. In the packing, the aromatic rings with nitro groups of one layer fill spaces between aromatic rings with nitro groups of the adjacent layers.     

Anticancer agent development. 4. X-ray crystal structure and intermolecular crystal lattice interactions of methyltrans-4,5-dihydro-4-acetoxymethyl-5-(3,4,5-trimethoxyphenyl)-2-(3,4-methylenedioxyphenyl)-3-furancarboxylate

The title compound, C₂₅H₂₆O₁₀,M ^r=486.48, crystallized from methanol in the acentric space group P2₁,2₁2₁, witha=7.617(3),b, 12.703(3),c=24.408(3) Å,V=2362 ų,D ^calc=1.37 g cm^–3 and=0.66 cm^–1 forZ=4. Least-squares refinement of 1417 observed [F ^o5(F ^o)] reflections led to the final agreement index ofR=0.044. The observed structure reveals atrans relationship for the 4-acetoxymethyl and 5-aryl substituents. The 4,5-dihydrofuran ring system assumes a slight envelope conformation. Several intermolecular van der Waals interactions of note occur in this compound.     

Solid-phase synthesis and crystal structure of 5(3-nitrophenyl)-3,7-diphenyl-4H,6H-1,2-diazepine

The title compound, 5-(3-nitrophenyl)-3,7-diphenyl-4H,6H-1,2-diazepine (C₂₃H₁₉N₃O₂), was synthesized, in 76% yield, by one-pot multicomponent solid-phase reaction of 3-nitrobenzylidene phenyl ketone, acetophenone and hydrazine, using the catalyst bismuth nitrate, co-catalyst ZnCl₂, adsorbed on neutral alumina, at 110°C. The compound was characterized by spectral methods and X-ray diffraction studies. The crystals are monoclinic, space group P2₁/c: a = 12.186(2), b = 14.769(3), c = 11.046(2) Å, β = 115.023(3)°, Z = 4; R = 0.0418 for 2576 observed reflections. The diazepine ring assumes a twist chair conformation. The dihedral angles between the mean planes through the diazepine ring and the nitrophenyl rings and two phenyl are: 89.19(5)°, 45.85(5)° and 20.80(6)°, respectively. The crystal structure is stabilized by C-H…N, C-H…O, C-H…π hydrogen bonds and π-π-stacking interactions.     

Crystal Structure and Computational Study of 5-Ethyl-4-(4-Methoxyphenethyl)-4,5-Dihydro-3H-1,2,4-Triazol-3-One and 4-(4-Methoxyphenethyl)-5-Propyl-4,5-Dihydro-3H-1,2,4-Triazol-3-One

Crystallography Reports - Molecular structures of compounds 5-ethyl-4-(4-methoxyphenethyl)-4,5-dihydro-3H-1,2,4-triazol-3-one, (C13H17N3O2) (I) and...     

Molecular and crystal structure of 2-amino-4-(tricyclo[3.3.1.1.3,7]decyl-1)-6-N-methyl-piperazino-1,3,5-triazine

The crystal and molecular structure of the title compound has been determined by X-ray diffraction. The compound crystallizes in the rhombohedral space groupR3 witha=b=c=17.804(9)Å,===116.48(2)° andZ=6. The structure was solved by direct methods and a full-matrix least-squares refinement converged to a finalR=0.061 for 1922 unique reflections. The adamantyl moiety is statically disordered in the crystal structure, and adopts two conformations related by the rotation of approximately 60° about the C(4)-C(9) bond. A hydrogen bond between N(7)N(21) arranges molecules into hexamers stacked along the threefold axis and provides for empty hydrophobic channels bounded by the adamantyl groups.