Structure of fruticuline B: A new natural anthracene quinodimethide of abietanoid origin

The title compound is C₁₉H₁₈O₄·1/2 CH₃OH, triclinic,P¯1,a=9.891(2),b=13.273(4),c=13.860(4) Å,a=66.47(2),=86.91(2), and =85.59(2)°. The structure was solved by direct methods and refined by least-squares techniques to anR factor of 0.082 for 2282 observed reflections. The X-ray structure uniquely resolves the one remaining ambiguity, namely the assignment of the correct structure4. There are two crystallographically independent molecules (A and B) and one disordered methanol molecule. Both molecular skeletons show small distortions from planarity with inclinations of 1.7 and 4.0° between the outermost rings A/C in molecules A and B, respectively. Intramolecular hydrogen bonds of the form O(3A)-HO(2A) and O(3B)-HO(2B) are observed in molecules A and B, respectively. The molecules are linked by pairs of O(3A)-HO(2B) and O(3B)-HO(2A) hydrogen bonds. The dimerlike structures are stabilized by intermolecular C-HO interactions and van der Waals forces.     

Molecular structure and some reactivity aspects of 2,6-diamino-4(3H)-pyrimidinone monohydrate

Crystals of C₄H₆N₄O·H₂O are orthorhombic:Pbca,a=16.721(2),b=4.242(1),c=18.293(2)Å,Z=8. The structure has been solved by direct methods and refined by full-matrix least-squares techniques toR=0.046 for 1252 unique reflections. The structure consists of approximately planar molecules of the 3(H)4-one tautomer. Delocalization of the ring and the C=O-electrons, and conjugation of the lone-pair electrons of the amine groups with the pyrimidinone nucleus are observed. The molecules are connected by O-HO, N-HN, and N-HO hydrogen bonds. The molecular structure clarifies the chemical properties of the compound.     

Crystal structure of a nucleoside analogue, 2′,3′-dideoxy-3′-fluoro-5-chlorocytidine

The title compound, 1-(2,3-dideoxy-3-fluoro--d-erythro pentofuranos-1-yl)-5-chlorocytosine, crystallises in the orthorhombic space groupP2₁2₁2₁ witha=5.142(1),b=14.177(2),c=15.721(2) Å,Z=4. The crystal structure was solved by the heavy atom method and refined by full-matrix least-squares method to a finalR value of 0.031 for 1629 unique observed reflections. The N-glycosidic torsion angle is –156.1(2)° and the sugar moiety is anti to the cytosine base. The sugar pucker is ₂ ³ T withP=178.2(1)° and=31(1)°. The atom 05 is in a +sc conformation with respect to the furanose ring. The molecular packing in the crystal is stabilized by N-HN, N-HO, O-HO hydrogen bonds and C-HO close contacts.     

Crystal structure of 4,6-dinitro-1-(5-tetrazolyl)-1H-indazole trihydrate

The title compound, C₈H₄N₈O₄·3H₂O, crystallizes in space groupP¯1 with cell constantsa=7.022(1),b=9.507(2),c=10.906(2) Å,=84.99(1),=71.89(1),=72.56(1)°,Z=2, andV _c =660.2 ų. The structure was solved by direct methods using diffractometer data and was refined by full-matrix least-squares methods to anR value of 0.060 for 2112 observed reflections. The molecule, consisting of a phenyl ring fused to a pyrazole ring with a tetrazole ring connected to it equatorially, is planar except for the N(7) nitro-group oxygen atoms. The structure is stabilized by a three-dimensional network of O-HO, O-HN, and N-HO hydrogen bonds through the water molecules.     

Crystal structure of μ-adeninatobis (methylmercury (II)) perchlorate monohydrate

The title compound belongs to the triclinic space groupP¯1,a= 8.189 Å,b = 9.863 Å,c = 10.726 Å, = 69.93 °, = 68.62 °, = 73.66 °, andZ = 2. The structure was refined on 1337 observed reflections to anR factor of 0.042. The crystals contain [adeninato(CH₃Hg)₂]⁺ complex cations in which mercury is linearly bonded to N(7) and N(9) of a deprotonated adenine ring. Centrosymmetrically related complex cations are paired via two N(6)-H(6) N(l) hydrogen bonds. Those planar units are stacked in the crystal with a distance of 3.4 Å between rings. The water molecule and the ClO₄ ^-ion are involved in hydrogen bonding and HgO contacts. This structure identifies N(7) as the best residual coordination site after H(9) has been substituted by CH₃Hg.     

Crystal structure of hexa(3,5-dicarboxypyridine)potassium tetrabromoaurate(III)

The title complex has been prepared, and characterized by X-ray crystallography. The crystals are rhombohedral, space groupR32, witha=20.954(5),c=9.753(1) Å,Z=3, andR _F =0.070 for 680 observed MoK reflections. The structure consists of a packing of hexa(3,5-dicarboxypyridine) potassium cations and tetrabromoaurate(III) anions. The potassium atom is surrounded by equivalent oxygen atoms to form a KO₆ octahedron with a very short K-O distance of 2.56(1) Å. The AuBr ₄ ^– group exhibits orientational disorder with a mean bond length of 2.38(1) Å. Two symmetric strong hydrogen bonds (linear OHO and bent NHN) are found in the crystal structure. The nearly planar organic ligands are interlinked by hydrogen bonds to form parallel sheets which approximately correspond to the (003) family of planes. The potassium atoms lying in between these sheets connect them into a three-dimensional network.On leave from Central Laboratory, Nankai University, Tianjin, China.     

Hydrogen-bonded coordination network in crystal structures of [Cu(3-PM)4Cl2] and [Cu(4-PM)4Cl]Cl, (PM = pyridylmethanol)

The crystal and molecular structures of [Cu(3-PM)₄Cl₂] (1) and [Cu(4-PM)₄Cl]Cl (2) have been determinated by X-ray crystallography. Complex 1 crystallizes in the triclinic system, space group P–1, with lattice parameters a = 7.972(2) Å, b = 8.293(2) Å, c = 10.707(2) Å, = 105.73(3)°, = 90.04(3)°, = 110.38(3)°, and Z = 1 at 100 K. The coordination geometry of each Cu atom is approximately octahedral formed by four nitrogen atoms of pyridine rings of 3-pyridylmethanol molecules in the equatorial plane and two chlorine atoms occupying the axial positions. The O—HsO, C—HsCl, and O—HsCl intermolecular hydrogen bonds and s stacking link the molecules in 3-D hydrogen-bonded coordination network. Complex 2 crystallizes in the tetragonal system, space group P4/n, with lattice parameters a = 10.464(1) Å, c = 11.339(2) Å, and Z = 2 at 217 K and a = 10.352(1) Å, c = 11.201(2) Å, and Z = 2 at 293 K. The coordination geometry of Cu atom in the [Cu(4-PM)₄Cl]⁺ ion is approximately square pyramidal formed by four nitrogen atoms of pyridine rings of 4-pyridylmethanol molecules in equatorial plane and one chlorine atom in axial position. The O—HsCl and C—HsCl intermolecular hydrogen bonds link the molecules in 2-D hydrogen-bonded coordination network.     

Crystal and molecular structure of tetra-n-butylammoniumbis(stilbenedithiolato)-nickelate(III)

The crystal and molecular structure of the title compound, C₄₄H₅₆NS₄Ni, are reported. Crystals are triclinic, space groupP¯1 (No. 2) withZ=2 in a unit cell of dimensionsa=8.874(2) Å,b=9.549(5) Å,c=26.025(7) Å,=97.22(3)°,=95.06(2)°, and=98.75(3)°. The structure was solved by Patterson and Fourier methods and refined by full-matrix least squares toR=0.062 for 2910 unique diffractometer data. The metal atom of the anion has an approximate square-planar configuration and the nitrogen atom of the cation an approximate tetrahedral configuration. The anions as well as the cations are well separated, the closest NiNi and NN approaches being the lattice repeat of 8.874(2) Å.     

Crystal and molecular structure of 3-dimethylaminobenzoic acid

The title compound C₉H₁₁NO₂ is triclinic, space group P¯1, with the cell dimensionsa=7.022(1),b=7.476(2),c=8.957 (1) Å,=87.02(2),=110.88(1),=99.10(1)°,V=433.8(4) ų,Z=2,M _r =165.2,Do=1.27,Dx=1.26 mg/m³,F(000)=176,T=293 K,R=0.057 for 939 observed reflections. The molecules are packed as centrosymmetric hydrogen bonded dimers with an O-HO distance of 2.626(3) Å. The COOH group is rotated by 1.7(1)° about the exocyclic C(1)-C(7) bond out of the benzene ring plane. The molecules lie on (0 2-1) plane for which thed value is found to be 3.378 Å which is very close to the mean separation between the parallel packed benezene rings [3.347(4) Å]. The entire molecule is planar except for the two methyl groups attached to the nitrogen atom. The N atom is free from any binding of either type C-HN or O-HN.N. C. L. Communication No. 4699.     

Two acetylamino derivatives of 2,4-bis(trichloromethyl)-1,3-benzdioxin showing different types of hydrogen bonding: (a) (C13C)CH⋯O=C and (b) N-H⋯O=C

8-Acetylamino-6-methyl-2,4-bis(trichloromethyl)-1,3-benzdioxin, (I), is monoclinic,P2₁/c,a=15.174(4),b=11.977(7),c=9.911(3)Å,=99.72(2)°. 6-Acetylamino-2,4-bis(trichloromethyl)-1,3-benzdioxin, (II), is monoclinic,P2₁/_n,a=5.927(4),b=40.623(1),c =7.120(3)Å,=91.39(4)°. In compound (I) the imino hydrogen atom is locked in an intramolecular hydrogen bond to the proximate oxygen atom of the heterocyclic ring and is not available for intermolecular hydrogen bonding. Instead the weakly acidic hydrogen atom [Cl₃C-C(2)]H takes part in a hydrogen bond to the carbonyl oxygen atom in another molecule. In compound (II) a normal intermolecular hydrogen bond of the type N-HO=C occurs. The 6-acetylam-ino group is twisted about the (C_Ar-N) bond such that the angles NHO=C, C_ArH_ArO=C, NHOH_ArC_Ar, at the carbonyl oxygen group total 360° (where NH is in the related molecule). The packing in both compounds takes the form of infinite chains and in compound (II) partial overlap of the aromatic ring and the acetylamino group, with very little offset, also occurs.     

Crystal and molecular structure of cesium isothiocyanatotrimethylaluminate,Cs[Al(CH3)3NCS]

The crystal structure of the title compound has been determined from three-dimensional X-ray diffraction data, and refined by full-matrix least-squares techniques. The crystals belong to the monoclinic space groupP2₁/c, witha = 8.849(4),b = 13.798(5),c = 7.943(4) Å, = 102.98(3) °, andD _x = 1.85g cm^–3 forZ = 4. The finalR factor for 1283 observed reflections is 0.046. The aluminum atom is bonded to the nitrogen atom of the thiocyanate ligand, where the Al-N bond length is 1.94(1) Å. The SCN is linear, and the CN-Al angle is 175(1) °. The cesium ion exhibits four contacts less than 3.60 Å: Cs C(thiocyanate) = 3.39(1) Å, Cs C(methyl) = 3.52(1) Å, Cs C.(methyl) = 3.56(1) Å, and Cs N = 3.575(9) Å. The closest Cs S is 3.772(3) Å.     

Crystal and molecular structure of (+)-6,7∶8,9∶10,11-tri-O-isopropylidene-2,3-dideoxy-d-arabino-l-allo-undec-2-enono-1,4-lactone,C20H30O9

The crystal structure of the title lactone, C₂₀H₃₀O₉, a potential precursor of uncommon 11-carbon sugar derivatives, has been determined by single-crystal diffraction methods. The compound crystallizes in the orthorhombic space groupP2₁2₁2₁ witha=15.581(3),b=14.047(2),c=9.888(2) Å, andZ=4. The structure was solved by direct methods and refined by full-matrix least-squares toR=0.054. The absolute configuration of the seven stereogenic carbon atoms was deduced as 4R, 5R, 6R, 7R, 8S, 9R, 10R, being (R)-(+)-glyceraldehyde its progenitor. An intramolecular O-HO hydrogen bond is present. Weak interaction C-HO links the molecules in sheets parallel to the (100) plane.     

Crystal structure and conformation of N-(t-butoxycarbonyl)-L-isoleucyl-L-alanine benzylester

C₂₂N₂O₅H₃₂,M _r =404.5, monoclinic,C2,a=21.781(5),b=5.065(1),c=22.333(4)Å,=112.81(2)°,V=2271.1(9)ų,D _calc=1.148 g cm³, (CuK )=1.5418 Å,=5.89 cm^–1,F(000)=848, room temperature,R=0.058 for 2178 unique reflections [I2.5(I)]. The peptide linkage is in thetrans conformation. The molecule adopts the-sheet structure. The crystal structure is stabilized by a three-dimensional network of N-HO and C-HO hydrogen bonds.DCB Contribution No. 813.     

Structure,magnetic and IR studies of copper(II) diphenylphosphate dihydrate,Cu(DPhP)2·(H2O)2

The title compound has been synthesized, and characterized by means of X-ray, magnetic, and IR-spectroscopic measurements.The crystals of Cu(DPhP)₂(H₂O)₂(DPhP=diphenylphosphate) are monoclinic, space groupI2/c witha=24.126(6),b=8.510(2),c=12.333(3) Å,=90.73(5)° andZ=4. The structure was solved by the heavy-atom technique, and refined by full-matrix least-squares calculations to a finalR of 0.040 for 1494 reflections.The complex is centrosymmetric, and the Cu atom at a center of symmetry is four-fold coordinated with two oxygen atoms from two phosphate groups and two water molecules. The coordination about the Cu atom is square-planar, with Cu-O and Cu-O(W) distances 1.926(3) and 1.912(3) Å, respectively.The O(2) phosphate oxygen is an acceptor of two H bonds; one of them is an intramolecular O(W)-H(2)O(2) of 2.714(4) Å, and the other is an intermolecularO(W)-H(1)O(2ⁱ) of 2.667(4) Å. Their presence is also deduced from the IR spectrum of this compound at 3250 and 3000 cm^–1, respectively.The calculated magnetic moment value of 1.92 B.M. corresponds to that of the monomeric copper(II) complexes including those of some alkyl phosphates.     

Crystal and molecular structure ofp-aminobenzene sulfonacetamide sodium [sulfacetamide sodium] monohydrate

The crystal and molecular structure ofp-aminobenzene sulfonacetamide sodium, C₈H₉N₂NaO₃S·H₂O, an important substituted sulfa drug, has been determined from diffractometric data using MoK radiation. The crystals are monoclinic, witha=6.614(2),b=23.788(6),c=7.012(2) Å,=103.13(2)°, and space groupP2₁/c. The structure was solved by the heavyatom method, and refined by full-matrix least squares to a finalR value of 0.040 with 1435 unique reflections. In packing, the molecules form dimers through pairs of N-HN and N-HO hydrogen bonds. The molecules are further stabilized by O-HO and O-HN hydrogen bonds.     

Crystal structure of a nucleoside analog, 2′,3′-dideoxy-3′-azido-5-chlorocytidine

The title compound, l-(2,3-dideoxy-3-azido--D-erythro pentofuranos-1-yl)-5-chlorocytosine, crystallizes in the orthorhombic space groupP2₁2₁2₁ witha=5.840(1),b=13.780(1),c=15.396(2)Å,Z=4. The structure was solved by direct methods and refined by full-matrix least-squares calculations to a finalR value of 0.033 for 1688 unique observed reflections. The N-glycosidic torsion angle has a value of –160.8(1)°, in the and range. The sugar pucker is ₂ ³ T withP=180(1)° and=34(1)°. The C4–C5 conformation is +sc with =50.8(2)°. The azido group is nonlinear and oriented trans to the C3–C4 bond. The molecular packing in the crystalline space is stabilized by N-HN, N-HO, O-HO hydrogen bonds and C-HO close contacts.     

Crystal structure of racemic 5-(p-nitrobenzoylamino)-5-methyl-4-oxo-1,3-dioxane

C₁₂H₁₂N₂O₆ crystallized from methanol in the monoclinic space group P2₁/c (Z=4) witha=13.333(4),b=10.154(3),c=9.597(2) Å and=102.37(2)°.M _r=280.24,V=1269.1(6) ų,D _x=1.466 g cm^–3,(Mo K)=0.71069 Å,=1.29 cm^–1,T=295 K. The structure was solved by direct methods and refined by full-matrix least-squares to a finalR (R _w)=0.049 (0.057) for 916 observed reflections. The molecules are linked by strong N-HO(4) hydrogen bonds with NO distance of 2.995(4) Å. The infinite racemic chains run in [001] direction.     

Crystal and molecular structure of (2-amino-4-methyl-1-pyridinio) cyanoborane

The crystal structure of the title compound, C₇H₁₀N₃B, has been determined by X-ray diffraction using CuK radiation. The crystals are monoclinic,P2₁/c witha=6.941(2),b=15.961(3),c=7.739(2) Å,=90.5(2)° andZ=4. The structure was solved by direct methods, and refined by full matrix least squares to a finalR-value of 056 with 833 observed reflections. The molecule is in the elongated form, but is not planar; the torsion angle C(2)-N(1)-B-C(8) is 82.9(4)°. The bond distances N(1)-B=1.587(5) Å; B-C(8)=1.586(6) Å; C(8)N(3)=1.134(5) Å. The B-C-N moiety is slightly [176.9(4)°] nonlinear. The molecules are linked by weak hydrogen bonds N(2)-H(1N)N(3), N(2)-N(3)=3.055(5) Å and N(2)-H(2N)N(3), N(2)-N(3)=3.165 Å.     

Crystal and molecular structure of glycinium diphenylphosphate

The crystal and molecular structure of glycinium diphenylphosphate, C₁₄H₁₆NO₆P, has been determined by X-ray methods. The crystals are orthorhombic:Pbca (No. 61),a=11.412(3),b=24.624(7),c=10.775(3) Å,Z=8. The structure was solved by direct methods and refined to anR value of 0.043 for 1289 nonzero independent amplitudes. The molecule exists in the structure as⁺NH₃CH₂CO₂H,(C₆H₅O)₂PO ₂ ^– and is planar except for the N atom, which deviates by 0.49 Å from the plane defined by C(1), C(2), O(5), and O(6) atoms, respectively. The conformation of the diphenylphosphate anion isgauche with respect to both P-O ester bonds. There are four crystallographically independent hydrogen bonds, three of the N-HO type and one of the O-HO type.     

Crystal structure of a nucleoside analog: 2′,3′-dideoxy-3′-fluoro-5-bromocytidine

The title compound crystallizes in the orthorhombic space groupP2₁2₁2₁ witha=5.084(1),b=14.322(3),c=16.065(2)Å,Z=4. The structure was solved by the heavy atom method and refined by full-matrix least-squares calculations to a finalR value of 0.033 for 1106 unique observed reflections. The N-glycosidic torsion anglex has a value of –153.7(4)°, in the anti-range. The sugar pucker is²T₃ withP=175(1)° and=30(1)°. The C4-C5 conformation is + sc with =46.7(7)°. The structure is stabilized by N-HN, N-HO and O-HO hydrogen bonds and C-HO close contacts.