Crystal structure and charge distribution for 20 oximino-5α-pregn-16-eno[3, 4,-c]-1′2′5′-oxadiazole (HS998)

The crystal structure of the modified steroid, 20 oximino-5 pregn-eno [3, 4-c] 125 oxadiazole (HS998) using X-ray diffraction is reported. HS998 crystallizes in the orthorhombic space groupP2₁2₁2₁, having cell parametersa=13.465(3),b=18.792(4),c=7.598(2) Å;Z=4. The structure was solved by direct methods and refined by full matrix least squares toR=0.060 for 3478 reflections.     

Crystal structure of 8-(3,4-dimethylphenoxy)-16H dinaphtho[2,1-d:1′,2′-g] dioxaphosphocin 8-oxide

The title compound, C₂₉H₂₃O₄P crystallizes in the triclinic space group witha=9.636(1),b=10.327(1),c=13.406(1) Å, =102.22(1), =100.59(1), =109.84(1)^o.V=1178.1(2) ų,Z=2,D _cal=1.32 M gm^–3, (CuK)=6.16 cm^–1, (CuK)=1.5418 Å andT=295K. The structure was solved by direct methods and refined by full-matrix least-squares method to a finalR=0.052 andwR=0.063 for 2708 reflections withl3(l). The napthalene ring A lies perpendicular to the best plane of the phenyl ring [91.6(1)^o] and the ring B orients at an angle of 55.7(1)^o with this plane and is inclined at an angle of 77.8(1)^o with ring A. The heterocyclic phosphorous eight-membered ring assumes a distorted boat conformation.DCB Contribution No. 822.     

Crystal and Molecular Structure Studies of 1′-Benzyl-8-(4-fluorobenzyl)-8-azaspiro[bicyclo-[3.2.1]octane-3,4′-imidazolodine]-2′,5′-dione

Abstract  

The title compound, C₂₃H₂₃FN₃O₂ has been synthesized and the structure was investigated by X-ray diffraction studies. The compound crystallizes in the triclinic crystal class in the space group P[`1]P\overline{1} with cell parameters a = 9.345(2) ?, b = 10.940(3) ?, c = 11.986(4) ?, α = 72.349(6)°, β = 68.106(18)°, γ = 66.867(5)°, Z = 2 and V = 1027.8(5) ?³. The hydantoin ring adopts a planar conformation and is affected by the π conjugation. The pyrrolidine and piperidine rings in the bicyclo octane moiety adopt envelope and chair conformations respectively. The structure exhibits both inter and intramolecular hydrogen bonds of the type N–H···O, C–H···O and C–H···N. One of the oxygen atoms attached to the hydantoin ring simultaneously accepts two hydrogen bonds to form a three centered hydrogen bonding pattern.     

The molecular structure of acetato[2-(pyridin-2′-yl)phenyl]mercury(II)

The crystal structure of the title compound was determined by X-ray crystallography. The compound crystallizes in the monoclinic crystal system witha=8.152(4),b=17.994(7),c=8.634(9) Å, =108.92(5)°, space group P2₁/c (N:14),V=1198.02 ų,Z=4. The mercuryl(II) atom forms two strong, almost colinear bonds (bond angle 176.1(4)°) with a carbon of the phenyl ring (Hg–C=1.99(1) Å) and one of the acetate oxygen atoms (Hg–O(1)=2.005(7) Å). These primary bonds are supplemented by secondary intramolecular interactions with the pyridine nitrogen (Hg...N=2.727(9) Å) and the other acetate oxygen (Hg...O(2)=2.925(8) Å), although the latter is very weak and the acetate anion therefore practically monodentate. Weak additional intermolecular Hg–C and Hg–O(1)interactions contribute to the lattice structure.     

Crystal structure of 2,5-cyclohexadien-4-one-spiro-3′-(2′-methylthio-5′,5′-dimethyl-1′-pyrroline)

The crystal structure of the pyrrole derivative 2,5-cyclohexadien-4-one-spiro-3′-(2′-methylthio-5′,5′-dimethyl-1′-pyrroline) is determined by X-ray diffraction. Two independent molecules have similar structures and close geometric parameters but differ in configuration of the pyrrole ring and orientation of the thiomethyl group with respect to the pyrrole ring.     

Synthesis and crystal structure of 1-(1′,3′-dimethyl-5′-chloropyrazol-4′-carbonyl′-3-(2′-chlorophenyl)-5-amino-4-cyanopyrazole

The title compound 1-(1,3-dimethyl-5-chloropyrazol-4-carbonyl)-3-(2-chlorophenyl)-5-amino-4-cyanopyrazole (C₁₆H₁₂Cl₂N₆O) has been synthesized and characterized by X-ray diffraction: Triclinic, space group P1, with a = 8.6712(8) Å, b = 9.5091(10) Å, c = 11.2170(11) Å = 71.531(2)°, = 84.683(2)°, = 74.099(2)° Z = 2; V = 843.7(14) ų. C(10), O(1), C(11), and N(2) atoms are coplanar with the average deviation of 0.0071 Å, which form 11.03° and 43.93° dihedral angles with pyrazole planes (I) and (II), respectively.     

Crystal structure of 17β-hydroxy-17α-methyl-5α-androstano [2,3-C] Furazan (Furazabol)

The crystal and molecular structure of 17-hydroxy-17-5-androstano [2,3-C] Furazan, Furazabol (C₂₀H₂₄N₂O₂), has been determined by direct methods and refined by full matrix least squares to a final R of 0.0528 for 1927 observed reflections and 216 parameters, CuK, = 1.54178 Å. The compound crystallizes with two molecules in the asymmetric unit, Z = 4, Dc = 1.131 Mg m^–3 space group P2₁, with unit cell parameters a = 18.747(3), b = 6.346(5), c = 15.647(4) Å, = 99.96(2)°, V = 1833.9 ų, (CuK) = 0.584 mm^–1. Whilst the two independent molecules have similar overall geometry there are small differences in bond lengths, bond angles and torsion angles in rings A and D and significant conformational differences in ring A. The A ring adopts a half-chair conformation in molecule A and an intermediate between a half-chair and a sofa in molecule B. The D ring in molecule A has a 13/14 half-chair conformation and in molecule B a conformation between an envelope and half-chair.     

The structure of Wallach's compound. Single-crystal X-ray structure determination oftrans-2,5-bis(trichloromethyl)-N-(1′-hydroxy-2′,2′,2′-trichloroethyl)-4-imino-1,3-dioxolane

The structure of Wallach's compound, C₇H₄O₃NCl₉, prepared in 1874 from concentrated aqueous solutions of potassium cyanide and chloral hydrate, has long been undecided. By single crystal X-ray crystallography it has now been established astrans-2,5-bis(trichloromethyl)-N-(1-hydroxy-2,2,2-trichloroethyl)-4-imino-1,3-dioxolane, confirming the tentative assignment by¹H and¹³C NMR spectrography. The title compound is monoclinic,P2₁/c;a=8.445 (1),b=10.948(1),c=17.923(4) Å;=94.36(1)°;Z=4. The structure was solved by direct methods, from data collected at room temperature on an Enraf-Nonius CAD4 diffractometer, and refined by least squares to a finalR value of 0.041 using 2101 reflections.     

Crystal structure of syn-1-acetyl-9′aH-8′- methoxyspiro[indole-3,2′-oxeto[3′,2′:4,5]furo[3,2-g][1] benzopyran]2,6′-dione

The crystal structure of syn-1-acetyl-9a-hydro-8-methoxyspiro[3H-indole-3,2(2aH) oxeto[3,2-g]furo[3,2-g]benzo[ b]pyran-2,6-dione 1 was determined by X-ray diffraction analysis. It possesses P2(1)/c space group symmetry, with a = 12.391(3), b = 15.035(3), c = 9.5435(19) Å, = 93.66(3), and D _calc. = 1.517 Mg/m³ for Z = 4.     

The crystal and molecular structure of spiro[1-(S)-Br-3-(S)-H-4-(R)-l-(1′ R,2′ S,5′R)-menthyloxy-5-oxo-6-oxa-bicyclo[3.1.0]hexane-2,3′-(R)-(4′-(R)-diphenylmethoxy-5′-l-(1′ R,2′ S,5′ R)-menthyloxy-butyrolactone)]

Crystal structure of C₄₁H₅₃O₇Br has been determined by single-crystal X-ray diffraction. The compound crystalline in the orthorhombic space group P2₁2₁2₁, with a = 11.264(2), b = 12.058(2), c = 29.337(6) Å, Z = 4. The bond angles of cyclopropane moiety in the molecule are approximate to 60° and agree with theoretic values of the internal angles in a cyclopropane, and two chiral menthyloxy groups are located above and under the whole chiral molecule, respectively. The configuration of the pentacyclic lactone is shown as envelope form.     

Crystal and molecular structure of 2-(2′-chloro-5′-nitrostyryl)benzoselenazole

The title compound C₁₅H₉ClN₂O₂Se (nsbse) is orthorhombic, witha=6.823(2),b=7.860(2),c=26.349(5) Å,Z=4,D _x =1.709,(MoK)=28.3 cm^–1,F(000)=720,T=298K in space groupP2₁2₁2₁. The structure was solved by heavy atom and Fourier methods and refined toR=0.045 for 1095 unique observed reflections. The molecule is almost planar, with a dihedral angle of 4.8(2)° between the benzoselenazole and phenyl rings. The C-Se-C angle in the selenazole ring is very small, 84.6(4)°, while the C-N-C angle in that ring is 113.7(7)°.     

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.     

Crystal structure of 5-(2′-aminophenyl)-2-dimethylamino-1,3,4-thiadiazole

The crystal structure of 5-(2′-Aminophenyl)-2-dimethylamino-1,3,4-thiazole is determined by X-ray diffraction. The compound is prepared by an unusual recyclization of 3-N, N-dimethylthioureidoquinazolin-4(3H)-one. The crystal is monoclinic, space group P2₁/c, a = 7.420(2) Å, b = 10.466(5) Å, c = 14.752(9) Å, β = 109.2(4)°, ρ_calcd = 1.359 g/cm³, and Z = 4 for the C₁₀H₁₂N₄S composition. The molecule consists of the thiadiazole and phenyl rings and the dimethylamine N(CH₃)₂ and amine NH₂ groups attached to the rings. The molecule as a whole is planar. The dihedral angle between the rings is 8.9°. The N(1) and N(4) atoms in the molecule are bound through the intramolecular interaction (2.76 Å). Molecules, which are linked in pairs by antiparallel hydrogen bonds, form a framework structure.     

Synthesis and structure of 5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-di(methylthio)-3,3′-biisoquinoline

Title compound, C₂₀H₂₄N₂S₂, crystallizes in the orthorhombic system, space group Pbca, with cell constants a = 5.1968(5) Å, b = 15.6692(11) Å, c = 22.3881(11) Å , Z = 4, T = 293 K, D_cal = 1.299 g cm^–3. The structure was solved by direct methods and refined to R value of 0.0465 for 1566 reflections. Two methylthio-octahydroisoquinoline parts of molecule are related by the center of symmetry and possess the trans conformation. This conformation is more energetically stable than cis but the molecule can rotate about the C(6)–C(6) central bond at room temperature (molecular mechanics calculations). There is a short intramolecular contact C(5)–H(51) N(1) in the molecule. The molecules in the crystal form molecular layers parallel to (001) crystallographic plane and the molecular packing is determined by the van der Waals forces only.     

Molecular and crystal structures of 8,9-dimethoxy-5′,5′-dimethyl-1,2,3,5,6,10b-hexahydropyrrolo[2,1-a]isoquinoline-1-spiro-2′-cyclohexane-3,1′,3′-trione

The crystal and molecular structures of 8,9-dimethoxy-5′,5′-dimethyl-1,2,3,5,6,10b-hexahydropyr-rolo[2,1-a]isoquinoline-1-spiro-2′-cyclohexane-3,1′,3′-trione are studied by X-ray diffraction. The unit cell parameters are a = 9.478(2) Å, b = 9.844(3) Å, c = 11.663(3) Å, α = 111.17(2)°, β = 99.56(2)°, γ = 105.82(2)°, Z = 2, and space group P1ˉ. The structure is solved by the direct method and refined to R = 0.0411 [I > 4σ(I)]. Conformational and geometric characteristics of the compound studied and the molecular packing in the crystal are discussed. __________ Translated from Kristallografiya, Vol. 45, No. 2, 2000, pp. 286–288. Original Russian Text Copyright ? 2000 by Lyakhov, Ivashkevich, Govorova, Mikhal’chuk.     

Crystal structure of 2,2,3-trimethyl-3-(2′,4′,5′-tricyanophenyl) cyclopentyl-1-acetic acid, methyl ester, C20H21N3O2

The title compound crystallizes in space group P2₁/n, with a = 14.600(2), b = 7.091(2), c = 18.211(5) Å, and = 103.67(2)°. Owing to the centric space group, both C(1) and C(3) chiral centers are either R or S. The acetate group is equatorial, the H(1) and the methyl group at C(3) are axial and reciprocally trans.     

Synthesis and crystal structure of 2-trifluoromethyl-1-[(2′-1H-tetrazole-5-yl-biphenyl-4-yl) methyl]benzimidazole

The crystal structure of 2-trifluoromethyl-1-[(2'-1H-tetrazle-5-yl-biphenyl-4-yl) methyl]-benzimidazole and a methylene chloride have been determined by X-ray crystallography. The compound crystallizes in the monoclinic space group, P2 ₁/n with cell dimensions a = 10.931(2) Å, b = 12.31(3) Å, c = 17.901(4) Å, = 102.45(3)°, V = 2352.9(8) ų, D _calc = 1.427 g/cm³, Z = 4, = 0.324 mm^–1, and F(000) = 1032, and its structure was refined to R ₁ = 0.0663 and wR ₂ = 0.1668 for 1910 observed reflections I > 2(I)). Intermolecular hydrogen bonds were identified between the N and H atoms of intermolecular benzimidazole group and tetrazole group.     

Crystal and molecular structure of [Pd(η5-C5H5) (bis-1,2-diphenylphosphinoethane)] [CF3SO3]

The crystal structure of the complex [Pd( ⁵-C₅ H₅) (PPh₂) CH₂CH₂PPh₂]⁺ [CF₃SO₃]^– has been determined from single crystal X-ray data and refined by least-squares methods toR=0.046. The monoclinic crystals have unit cell dimensionsa=9.832(3),b=12.104(4),c=13.765(4)Å,=111.22(3)°, space group P2₁, andz=2. In the cationic complex the palladium atom is coordinated to the ⁵-cyclopentadienyl moiety and to the phoshorus atoms of the chelating diphosphine. The arrangement of the two phosphorus atoms and the centroid of the cyclopentadienyl ring is approximately trigonal.     

Crystal structure of 4-phenyl-3,5-dioxacyclohexyl-1, 1′-cyclopentane-2′,3″-(1,5,8,11-tetraoxacyclotridecane)

The structure of the title compound is determined by X-ray diffraction (DAR-UMB diffractometer, θ-θ/2θ scan mode, MoK _α radiation, direct method). The crystal is monoclinic, a = 24.582(6) Å, b = 22.812(8) Å, c = 8.647(3) Å, γ = 60.64(2)°, ρ _calcd = 1.232 g/cm³ space group A2/a, and Z = 8 for C₂₂H₃₂O₆. The molecule consists of four fragments: 13-crown-4 (A), 1,3-dioxane (B), a five-membered ring (C) acting as a bridge between fragments A and B, and a phenyl ring (D). Introduction of the bulky ring C as a bridge into the molecule results in significant deviations (up to ±0.014 Å) of the ether O atoms from planarity. The conformation of the macrocyclic fragment is [3433] according to the Dale notation. The C—H?O 1,4-interactions, which are energetically favorable occur in the propylene part of 13-crown-4: the C(2)?O(5) and C(4)?O(1) distances are 2.82 Å. The molecules in the structure form planar networks parallel to the xy plane. The intermolecular contacts correspond to the van der Waals interactions.