2α-Hydroxy-3α-[N-alkyl(aryl)]pinanoamines. Part I. Preparation and nature of some Schiff bases of 2α-hydroxypinan-3-one. Crystal and molecular structure of α-hydroxy-2,6,6-trimethylbicyclo[3.1.1]hepta-3-ylidenaminobenzene

Some Schiff bases of 2-hydroxypinan-3-one, being precursors of 2-hydroxy3-[N-alkyl(aryl)]pinanoamines, were obtained. The crystal structure of racemic 2-hydroxy-2,6,6-trimethylbicyclo-[3.1. 1]hept-3-ylidenaminobenzene was determined. The Schiff bases were obtained in two forms: solid form (racemate) and liquid form (optically pure). As it appeared from crystallographic studies of the racemic form, in the solid state there are intramolecular-H-bonded dimers.     

Reactivity of 6α,7α-epoxyhimachal-2-ene and crystal structures of 2α,3α-dibromocyclopropanehimachal-5,7-diene and 2α,3α-dibromocyclopropane-6α,7α-epoxyhimachalane

We report here the reactivity of 6,7-epoxyhimachal-2-ene with dibromocarbene generated in situ by phase-transfer catalysis. The stereochemistry of products resulting from dibromocyclopropanation has been established by X-ray crystallography. Compound 3 is orthorhombic P2₁2₁2₁ with a = 7.549 (1), b = 8.432 (1), c = 24.469 (1) Å, V = 1559.8 (5) ų, Z = 4 and compound 5 is monoclinic P2₁ with a = 8.779 (1), b = 15.684 (1), c = 12.111 (1) Å, = 91.869 (1)°, V = 1666.7 (4) ų and Z = 4.     

Synthesis and Crystal Structure of 3-Quinuclidinyl α-(Cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate

Abstract The title compound 3-quinuclidinyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate was obtained by the reaction of methyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate with 3-quinuclidinol in n-heptane. Its structure was characterized by ¹H, ¹³C NMR, MS and X-ray single-crystal diffraction techniques: C₂₀H₂₅NO₃, M _r = 327.41, orthorhombic, space group P2₁2₁2₁ with a = 8.547(2), b = 11.428(4), c = 18.288(5) ?, V = 1786.3(9) ?³, Z = 4. The title compound comprises a tertiary α-hydroxy acid and a bicyclo[2.2.2]octan moiety. The crystal structure shows the presence of the intermolecular O(1)–H(1)···N(1) hydrogen bonds. Index Abstract The title compound, 3-quinuclidinyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate was obtained by the reaction of methyl α-(cyclopentyl-1-ene)-α-hydroxy-α-phenylacetate with 3-quinuclidinol in n-heptane and its crystal structure determined. The title compound comprises a tertiary α-hydroxy acid and a bicyclo[2.2.2]octan moiety. The crystal structure shows the presence of the intermolecular O(1)–H(1)···N(1) hydrogen bonds.      

Synthesis and structure analysis of 2-(2′-propanonylthio)-3-(o-methyl phenyl) quinazol-4(3H)-one

The three-dimensional molecular and crystal structure of 2-(2'-propanonylthio)3-(o-methyl phenyl)quinazol-4(3H)-one has been determined by X-ray crystallographic methods. This compound crystallizes in the orthorhombic space group P_bca with unit cell parameters: a=9.649(5), b=30.102(10), c=11.403(9)Å. It has been solved by direct methods and refined to a residual index of 0.054. The magnitude of torsion along C16— C11— N3— C4 bond is 93.5(4)°. The dihedral angle between the plane comprising all the ring atoms of quinazoline moiety and the atoms of the methyl substituted phenyl ring is 94.12(1)°. The crystal structure is stabilized by one intramolecular C— HsO interaction and three intermolecular C— HsN contacts.     

Structural studies of N-2-(3-picolyl)- and N-2-(4-picolyl)-N′-tolylthioureas

Reactions of 2-aminopicolines with 2- and 4-tolyl isothiocyanates yielded N-2-(4-picolyl)-N-4-tolylthiourea, 1, N-2-(3-picolyl)-N-4-tolylthiourea, 2, and N-2-(4-picolyl)-N-2-tolylthiourea, 3. Compound 1 is monoclinic, of space group P2₁/c with a = 7.456(1) Å, b = 13.135(3) Å, c = 13.959(3) Å, = 104.99(3)°, and V = 1320.5(5) ų with Z = 4, for d _calc = 1.294 g/cm³. Compound 2 is triclinic, of space group with a = 6.877(3) Å, b = 7.590(5) Å, c = 13.213(9) Å, = 78.38(2)°, = 77.96(4)°, = 86.36(4)°, and V = 660.5(7) ų with Z = 2, for d _calc = 1.294 g/cm³. Compound 3 is monoclinic, of space group P2₁/c with a = 12.604(2) Å, b = 15.592(3) Å, c = 6.875(2) Å, = 91.05(2)°, and V = 1350.9(2) ų with Z = 4, for d _calc = 1.265 g/cm³. The three thioureas are found in both solid state and solution in a conformation resulting from intramolecular hydrogen bonding. Compounds 1 and 3 present an intermolecular hydrogen bond involving the thione sulfur and the NH hydrogen, which is not present in 2 owing to the steric hindrance of the methyl group in the phenyl ring. The geometry of the molecule is affected by the position of the methyl groups on the pyridine and aryl rings.     

Structural study of nitrovinylindoles: (I) 2-methyl-3-(2′-methyl-2′-nitrovinyl)indole and (II) 3-(2′-nitrovinyl)indole

Compound (I) is 2-methyl-3-(2-methyl-2-nitrovinyl)indole, C₁₂H₁₂N₂O₂,M _r=216.24, monoclinic,P2₁/n,a=16.710(1),b=7.627(1),c=17.646(1) Å,=104.8(1)°,V=2174.7(1) ų,Z=8.D _x=1.321 g cm^–3, MoK, =0.71073 Å,=0.858 cm^–1,F(OOO)=912, room temperature,R=0.061 for 1956 observed reflections. Compound (II) is 3-(2-nitrovinyl)indole, C₁₀H₈N₂O₂,M _r=188.18, monoclinic,P2₁/n,a=10.178(1),b=10.608(1),c=8.411(1) Å,=105.5(2)°,V=875.0(1) ų,Z=4,D _x=1.4284 g cm^–3, CuK, =1.5418 Å,=8.068 cm^–1,F(000)=392, room temperature,R=0.040 for 1330 observed reflections. Compounds (I) and (II) have a similar geometry, the only significant difference lying in the rotation of the nitrovinyl chain. This feature could be responsible for the difference in biological activity. In both compounds, the molecules are associated, forming charge-transfer complexes.     

Anticancer agent development. 5. X-ray structure and1H nmr spectral analysis of (1α,2α,5α,6α)-2,6-bis(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo[3.3.0]octane-4,8-dione

The title compound, C₂₀H₁₄O₈, Mr=382.3, crystallized from chloroform in the centric space group P¯1 witha=6.516(4),b=6.798(3),c=9.545(7) Å,=85.31(5),=73.87(5), =79.59(4)°,V=399.2 ų, and D_calc=1.59 g cm^–3 forZ=1. Least-squares refinement of 1035 observed [F_o5(F_o)] reflections led to the final agreement index ofR=0.074. The molecule resides on a crystallographic center of inversion and is disordered into two different conformations. This manifests itself as a 50/50 disorder at O(4), C(2), and C(3). The observed structure reveals acis relationship between the bridgehead hydrogen atoms and the aryl rings. The 90 MHz¹H nmr spectrum of the title compound exhibits an AAXX spin system with a H(1)C(2) to H(1)C(3) and H(1)C(2) to H(1)C(3) coupling constant of 2.8 Hz. Computer spectral simulation and Karplus equation analysis are utilized to illustrate a relaxation of the torsion angles between H(1)C(2) and H(1)C(3), and H(1)C(2) and H(1)C(3) is solution.     

Polymorphism in Dethoxyprone,a steroidal anesthetic. II. Crystal and molecular structure of 11α-dimethylamino-2β-ethoxy-3α-hydroxy-5α-pregnan-20-one (Dethoxyprone,form II)

The crystal and molecular structure of 11-dimethylamino-2-ethoxy-3-hydroxy-5-pregnan-20-one (Dethoxyprone, formII) (C₂₅H₄₃NO₃) has been determined by direct methods, and refined to a finalR of 0.067 for 4508 observed reflections. The compound crystallizes in space groupP2₁2₁2₁ with cell dimensionsa=10.830 (2),b=12.703 (2),c=17.490 (1) Å;Z=4,D _x =1.12 g cm^–3, (CuK )=5.28 cm^–1. The rings of the steroid skeleton are trans connected. Rings A, B, and C have chair conformations, while ring D has a half-chair conformation. The molecules are hydrogen bonded in a head to tail fashion through the hydroxy and keto groups.     

Crystal and molecular structures of the 4-(1H)-pyridone (=L) lanthanide complexes {[GdL(NO3)3(H2O)]·CH3OH}2 and [DyL4(NO3)2](NO3) and of L2HNO3

The crystal structures of the title compounds have been determined by single crystal diffraction methods. Crystals of the dysprosium compound are monoclinic, space groupP2₁/c witha=14.133(4),b=13.438(5),c=14.401 (4)Å,=103.98(2)°,V=2654(1)ų,Z=4,D _c =1.82 g cm^–3, finalR=0.035. The Dy atom is eight-coordinate with a distorted dodecahedral coordination geometry involving two bidentate nitrate groups and four pyridone oxygen atoms. An erbium complex with analogous stoichiometry was also prepared but not structurally characterized. Crystals of the Gd compound are monoclinic, space groupP2₁/n, witha=11.226(2),b=9.075(2),c=16.737(3)Å,=93.88(3)°,V=1701(1)ų,Z=2,D _c =1.91 g cm^–3, finalR=0.042. Each Gd atom is bonded to one pyridone oxygen atom, a water molecule and three bidentate nitrate groups. An oxygen atom of one of the bidentate nitrates additionally serves to bridge pairs of Gd atoms so as to form a dinuclear complex in which each Gd atom is nine-coordinate with a tricapped trigonal prismatic geometry. Crystals of L₂HNO₃ are monoclinic, space groupI2/a witha=12.479(4),b=6.535(2),c=14.297(6)Å,=96.07(3)°,V=1159(1)ų,Z=4,D _c =1.45 g cm^–3, finalR=0.057. The pyridones are linked in pairs by very short (2.44 Å) symmetrical OHO hydrogen bonds. Each pair is further linked via a nitrate ion by means of N-HO(nitrate)H-N hydrogen bonds, so as to form an extended chevron-like pyridone-pyridone-nitrate-pyridone-pyridone array. Adjacent chains are linked via weak C-HO(NO₃) interactions.     

The crystal structure of 2-(α-hydroxy-βββ-trichloroethyl)-4-methylphenol and its relevance to the condensation of chloral hydrate and parasubstituted phenols

The product formed by the condensation ofp-cresol and chloral hydrate in the presence of anhydrous potassium carbonate is shown by single crystal X-ray crystallography to be 2-(-hydroxy--trichloroethyl)-4-methylphenol and its failure to cyclize to form a 1,3-benzdioxin is explained. The title compound is monoclinic, P2₁,/c,Z=4,a=12.316(1),b=8.8668(9),c=10.275(2) Å,=107.90(1)°     

Synthesis and crystal structure of [Y(NO3)3(OH2)3]·(Me2-16-crown-5)·H2O

The complex [Y(NO₃)₃(OH₂)₃]·(Me₂-16-crown-5)·H₂O has been prepared and its crystal and molecular structure determined using single crystal X-ray diffraction. The colorless crystals belong to the monoclinic space group P2₁/n with Z = 4. Lattice parameters are a = 10.420(1), b = 17.257(3), c = 14.646(2) Å, = 96.79(1)°, V = 2615.1(6) ų. The yttrium(III) ion is nine-coordinate, bonded to three bidentate nitrate groups and three water molecules. The average Y–O(nitrate) and Y–O(water) distances are 2.42(3) and 2.33(1) Å, respectively. The average HO–H···O hydrogen bonded separation is 2.767Å.     

f-Element/crown ether complexes. 20. Synthesis and structure of [Y(NO3)3(OH2)3]·1.5(15-crown-5)·Me2O

The title complex was prepared by the addition of 15-crown-5, dissolved in acetone, to a solution of Y(NO₃)₃·nH₂O in the same solvent. The crystal structure of this complex, determined by single-crystal X-ray diffraction using counter methods, was carried out on a crystal grown by slow evaporation of the reaction mixture at room temperature. [Y(NO₃)₃(OH₂)₃]·1.5(15-crown-5) Me₂CO crystallizes in the acentric space group, P2₁, with unit cell dataa=15.900(5),b=16.530(6),c=11.821(5) Å,=92.12(3)°,D _calc=1.53 g cm^–3 forZ=4. Each unit cell consists of two dimers of the formula unit. One crown molecule bridges two [Y(NO₃)₃(OH₂)₃] units via hydrogen bonding with one water molecule of each. The two remaining water molecules per metal moiety form three hydrogen bonds to another 15-crown-5 molecule and one to an acetone molecule. The average bonding parameters in the nine-coordinate metal complexes are Y-O(NO₃)=2.43(4) Å and Y-O(OH₂)=2.34(5) Å.For Part 19 see Rogers, 1987.     

Crystal and molecular structure of 4-(3-indolyl)butyric acid-picric acid 2/2 π complex

The title compound, IBA-PIC, is 2C₁₂H₁₃NO₂·2C₆H₃N₃O₇, triclinic,P¯1,a=7.137(1),b=15.355(4),c=18.282(5) Å,=79.72(2),=79.85(2), =76.87(2)°. The structure was solved by direct methods and refined by least-squares techniques to anR factor of 0.068 for 3395 observed reflections. The IBA-PIC complex occurs as two independent molecules with different conformations. The crystallographic evidence for a prominent overlapping between the phenyl and indole rings corroborates earlier conclusions from UV spectroscopy. Molecules of both IBA and picric acid lie approximately parallel to (100) in layers and -bonding interactions across the 3.55 Å spacing. The angles between the indole ring and carboxyl-group planes are 82.9 and 86.9° for the A and B molecules, respectively.     

Crystal structure of a (25R)-2α,3α-epoxy-5α-spirostan-6, 23-dione hemi-ethyl acetate solvate

The compound (25R)-2,3-epoxy-5-spirostan-6,23-dione, crystallizes as a hemi-ethyl acetate solvate, having two host molecules of similar conformation per molecule of ethyl acetate, in the asymmetric unit. The O atom of the epoxy group is -oriented. The presence of the epoxy group disturbs the chair conformation in the ring A of the steroidal nucleus. Ring A has a C5,C10 half-chair conformation. The six-membered rings B, C, and F have chair conformation as expected. The D ring adopts a C14-envelope conformation and the E ring is midway between a C22,O3 half-chair and a C22-envelope conformations. The A/B, B/C, and C/D ring junctions are trans. Crystal data: C₂₇H₃₈O₅·1/2C₄H₈O₂, Monoclinic, space group P2₁, a = 7.7363(18) b = 28.769(12) c = 12.038(6) Å, = 90.88(5), V = 2679.0(10) ų, Z = 4. The packing of the molecules is assumed to be dictated by van der Waals interactions and by intermolecular C—H ··· O hydrogen bonds.     

Polymorphism and design of noncentrosymmetric crystals of 4-hydroxybenzaldehyde-4-nitrophenylhydrazone and N′-(2-phenyl-1H-indole-3-aldehyde)-4-nitrophenylhydrazone

The products of crystallization of 4-hydroxybenzaldehyde-4-nitrophenylhydrazone (I) and N′-(2-phenyl-1H-indole-3-aldehyde)-4-nitrophenylhydrazone (II) from different solvents are studied by X-ray diffraction with the aim of examining the polymorphism of hydrazone derivatives. The structural features of the crystals prepared are analyzed. It is shown that, in the case when molecules of organic compounds with a high molecular hyperpolarizability are capable of forming stable acentric supramolecular associates in the crystal, knowledge of their polymorphism offers strong possibilities for designing the noncentrosymmetric crystal structure necessary for a manifestation of the nonlinear optical activity.     

Synthesis and structure determination of 3α-triphenylstannyl-cholest-5-ene

3-Triphenylstannylcholest-5-ene (1) has been synthesised and its molecular structure has been determined by single crystal X-ray diffraction. Refinement in the triclinic space groupP1 witha=7.805(6),b=7.862(5),c=32.351(10)Å, =90.87(8), =94.77(8) and =101.15(4)^o converged atR=0.063. One of the two crystallographically independent molecules in the unit cell has a patially disordered side chain. The bond lengths and valency angles about tin indicate some steric hindrance due to the proximity of one of the phenyl rings with the B ring of the steroid nucleus.     

Crystal and Molecular Structures and Acid–Base Equilibria of N-(4-Chlorophenyl)-2-Benzoylethylamine and Bis[3-(o-Chlorophenyl)-1-Phenylaminopropyl]diazene

Crystallography Reports - N-(Phenyl)-2-benzoylethylamine (I), N-(4-chlorophenyl)-2-benzoylethylamine (II), and N-(2-chlorophenyl)-2-benzoylethylamine hydrazone (III) were synthesized in the...     

Synthesis, Characterization, and Crystal Structures of 3-bromo-N′-(2-methoxybenzylidene)benzohydrazide and N′-(2-methoxybenzylidene)-3,4-methylenedioxybenzohydrazide

Abstract  

Two new hydrazone compounds, 3-bromo-N′-(2-methoxybenzylidene)benzohydrazide (1) and N′-(2-methoxybenzylidene)-3,4-methylenedioxybenzohydrazide (2), have been synthesized and characterized by elemental analysis, IR, and single crystal X-ray diffractions. Compound (1) crystallizes in the triclinic space group P1 with unit cell dimensions a = 8.4088(5) ?, b = 8.5398(5) ?, c = 10.6572(6) ?, α = 90.356(3)°, β = 102.868(3)°, γ = 97.987(3)°, V = 738.28(7) Ǻ³, Z = 2, R ₁ = 0.0406, and wR ₂ = 0.0804. Compound (2) crystallizes in the tetragonal space group P4₁ with unit cell dimensions a = b = 9.792(4) ?, c = 15.788(6) ?, V = 1513.8(10) Ǻ³, Z = 4, R ₁ = 0.0415, and wR ₂ = 0.0818. The molecules of both compounds display E configurations with respect to the C=N double bonds. In the crystal structure of (1), molecules are linked through N–H···O hydrogen bonds, forming chains running along the b axis. In the crystal structure of (2), molecules are linked through N–H···O hydrogen bonds, forming chains running along the c axis.     

Structural and electronic comparative analysis of aminopyridazines showing anti-GABA activity. Crystal structure of 2-(carboxy-3′-propyl)-3-amino-6-cyclohexylpyridazinium bromide.Ab initio Mulliken population analysis of the 6-phenyl-substituted analog compared to GABA

The crystal structure of 2-(carboxy-3-propyl)-3-amino-6-cyclohexylpyridazinium bromide has been determined by single-crystal X-ray diffraction techniques and refined by full-matrix least squares. The compound crystallized in the tri-clinic space groupP ¯1 witha=10.275(1),b=11.215(1),c=7.082(1) Å,=91.84(1),=102.21(1), =106.77(1)°, andZ=2. FinalR-factor is 0.045. The main structural results are very similar to the ones observed for the 6-phenyl analog. These two compounds are GABA-A antagonists.Ab initio molecular orbital calculations, with STO-3G and 4-31G basis sets, suggest that the exocyclic nitrogen accurately mimics the nitrogen atom of GABA.