Browsing by Author "Aydin A."

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2-(6-Oxo-3,4-diphenyl-1,6-dihydro-pyridazin-1-yl)acetic acid
(2007-11-09) Aydin A.; Doǧruer D.; Akkurt M.; Büyükgüngör O.
In the title compound, C18H14N2O3, the pyridazine ring makes dihedral angles of 72.73 (11) and 49.97 (10)° with the two phenyl rings. The dihedral angle between the two phenyl rings is 52.42 (12)°. The crystal structure is stabilized by inter-molecular O - H⋯O and C - H⋯O hydrogen-bonding inter-actions. © International Union of Crystallography 2007.
2-{2-[4-(4-Fluoro-phenyl)piperazin-1-yl]-2-oxoethyl}-6-(morpholin-4-yl) -4-phenyl-pyridazin-3(2H)-one
(2011-03-01) Aydin A.; Şüküroǧlu M.; Akkurt M.; Büyükgüngör O.
In the title compound, C26H28FN5O 3, the morpholine ring adopts a chair conformation. The piperazine ring is puckered [QT = 0.5437 (15) Å, θ = 8.89 (15) and φ = 357.2 (11)°]. The 1,6-dihydropyridazine ring makes dihedral angles of 28.03 (7) and 77.46 (7)° with the phenyl and benzene rings, respectively. In the crystal, molecules are linked along the c axis by C - H⋯O interactions and are flattened parallel to the ac plane. C - H⋯π interactions also contribute to the stability of the structure.
3-(4-Chloro-benzo-yl)-4-(4-chloro-phen-yl)-1-phenethyl-piperidin-4-ol
(2011-06-01) Aydin A.; Akkurt M.; Mete E.; Sahin E.; Gul H.
In the title compound, C26H25Cl2NO 2, the piperidine ring adopts a chair conformation with a cis configuration of the carbonyl and hy-droxy substituents. The dihedral angle between the aromatic rings of the chloro-benzene groups is 24.3 (2)°. The phenyl ring forms dihedral angles of 59.4 (3) and 44.1 (3)° with the benzene rings. In the crystal, mol-ecules are linked by inter-molecular O - H⋯N and C - H⋯O hydrogen bonds and C - H⋯π inter-actions into layers parallel to the bc plane.
3-[6-(2-Chlorobenzoyl)-2-oxo-2,3-dihydro-1,3-benzothiazol-3-yl] propanenitrile
(2006-12-01) Aydin A.; Akkurt M.; Önkol T.; Büyükgüngör O.
The title compound, C17H11ClN2O 2S, crystallizes with two crystallographically independent molecules in the asymmetric unit. In the molecular structure, there are intramolecular weak C-H⋯O hydrogen bonds, which consolidate the molecular conformation. © 2006 International Union of Crystallography All rights reserved.
3-Anilinomethyl-5-chloro-1,3 - Benzoxazol-2(3H)-one
(2012-05-01) Aydin A.; Soyer Z.; Akkurt M.; Büyükgüngör O.
In the title compound, C14H11ClN2O 2, the 2,3-dihydro-1,3-benzoxazole ring system is essentially planar [maximum deviation = 0.009 (2) Å] and makes a dihedral angle of 79.15 (7)°with the phenyl ring. Inter-molecular N - H⋯O and weak C - H⋯Cl hydrogen bonds occur in the crystal structure. © Aydn et al. 2012.
Crystal structure and Hirshfeld surface analysis of 1-(2,4-dichlorobenzyl)-5-methyl- N -(thiophene-2-sulfonyl)-1 H -pyrazole-3-carboxamide
(2018-01-01) Aydin A.; Akkurt M.; Gur Z.T.; Banoǧlu E.
In the title compound, C16 H13 Cl2 N3 O3 S2, the thiophene ring is disordered in a 0.762 (3):0.238 (3) ratio by an approximate 180°rotation of the ring around the S - C bond linking the ring to the sulfonyl unit. The dichlorobenzene group is also disordered over two sets of sites with the same occupancy ratio. The molecular conformation is stabilized by intramolecular C - H...Cl and C - H...N hydrogen bonds, forming rings with graph-set notation S(5). In the crystal, pairs of molecules are linked by N - H...O and C - H...O hydrogen bonds, forming inversion dimers with graph-set notation R 2 2 (8) and R 1 2 (11), which are connected by C - H...O hydrogen-bonding interactions into ribbons parallel to (100). The ribbons are further connected into a three-dimensional network by C - H...π interactions and π-π stacking interactions between benzene and thiophene rings, with centroid-to-centroid distances of 3.865 (2), 3.867 (7) and 3.853 (2) Å. Hirshfeld surface analysis has been used to confirm and quantify the supramolecular interactions.
Crystal Structure and Hirshfeld Surface Analysis of 1-(4-Chlorophenyl)-5-{4-[(2-methylphenyl)methoxy]phenyl}-1H-Pyrazole
(2021-01-01) Aydin A.; Akkurt M.; Turanli S.; Banoglu E.; Ozcelik N.
The aim of the study is to explore the crystal structure and performe Hirshfeld surface analysis of l-(4-chlorophenyl)-5-{4-[(2-methylphenyl)methoxy]phenyl}-1H-pyrazole. In the title compound, C23H19C1N2O, the 4-chlorophenyl, 2-methylphenyl and benzene rings are oriented with dihedral angles of 71.22(10), 31.82(9) and 59.76(9)°, respectively, with respect to the pyrazole ring. Pairs of molecules are linked by intermolecular C-H⋯O hydrogen contacts with R22(8) ring motifs forming sheets lying parallel to (100). Furthermore C-H⋯π interactions also contribute to stabilizing the molecular packing. A Hirshfeld surface analysis has been used to confirm and quantify the supramolecular interactions which indicate that the most important contributions for the crystal packing are from H⋯H (42.5%) and H⋯C/C⋯H (35%) and H⋯Cl/Cl⋯H (12%) interactions.
Crystal structure and Hirshfeld surface analysis of 2-[(1,3-benzoxazol-2-yl)sulfanyl]-N-(2-methoxyphenyl)acetamide
(2019-10-01) Aydin A.; Celikesir S.; Akkurt M.; Saylam M.; Pabuccuoglu V.
In the title compound, C16H14N2O3S, the 1,3-benzoxazole ring system is essentially planar (r.m.s deviation = 0.004Å) and makes a dihedral angle of 66.16(17)° with the benzene ring of the methoxyphenyl group. Two intramolecular N - H⋯O and N - H⋯N hydrogen bonds occur, forming S(5) and S(7) ring motifs, respectively. In the crystal, pairs of C - H⋯O hydrogen bonds link the molecules into inversion dimers with R 2 2(14) ring motifs, stacked along the b-axis direction. The inversion dimers are linked by C - H⋯π and π-π-stacking interactions [centroid-to-centroid distances = 3.631(2) and 3.631(2)Å], forming a three-dimensional network. Two-dimensional fingerprint plots associated with the Hirshfeld surface show that the largest contributions to the crystal packing come from H⋯H (39.3%), C⋯H/H⋯C (18.0%), O⋯H/H⋯O (15.6) and S⋯H/H⋯S (10.2%) interactions.
Crystal structure and Hirshfeld surface analysis of 4-(4-chlorophenyl)-5-methyl-3-{4-[(2-methylphenyl)methoxy]phenyl}-1,2-oxazole
(2021-04-01) Aydin A.; Akkurt M.; Turanli S.; Lengerli D.; Banoglu E.; Ozcelik N.D.
In the title compound, C24H20ClNO2, the mean planes of 4-chlorophenyl, 2-methylphenyl and phenylene rings make dihedral angles of 62.8 (2), 65.1 (3) and 15.1 (2)°, respectively, with the 5-methyl-1,2-oxazole ring. In the crystal, molecules are linked by intermolecular C-H⋯N, C-H⋯Cl, C-H⋯π contacts and π-π stacking interactions between the phenylene groups. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (48.7%), H⋯C/C⋯H (22.2%), Cl⋯H/H⋯Cl (8.8%), H⋯O/O⋯H (8.2%) and H⋯N/N⋯H (5.1%) interactions.
Crystal structure and theoretical study of (2E)-1-[4-hydroxy-3-(morpholin-4-ylmethyl)phenyl]-3-(thiophen-2-yl)prop-2-en-1-one
(2018-01-01) Yesilyurt F.; Aydin A.; Gul H.; Akkurt M.; Ozcelik N.
In the title compound, C18H19NO3S, the morpholine ring adopts a chair conformation. The thiophene ring forms dihedral angles of 26.04 (9) and 74.07 (10)° with the benzene ring and the mean plane of the morpholine ring, respectively. The molecular conformation is stabilized by an O - H⋯N hydrogen bond. In the crystal, molecules are connected through C - H⋯O hydrogen bonds, forming wave-like layers parallel to the ab plane, which are further linked into a three-dimensional network by C - H⋯π interactions involving the benzene rings and the methylene H atoms of the morpholine rings.
Crystal structure and theoretical study of N, N -bis[(5-chloro-2-oxo-2,3-dihydrobenzo[ d ]oxazol-3-yl)methyl]-2-phenylethanamine
(2018-01-01) Aydin A.; Soyer Z.; Akkurt M.; Büyükgüngör O.
In the molecular structure of the title compound, C24 H19 Cl2 N3 O4, the three C atoms of the central N,N-dimethylmethanamine moiety are bonded to the N atoms of the two 5-chloro-1,3-benzoxazol-2(3H)-one groups and to the methyl C atom of the methylbenzene group. One of the nine-membered 2,3-dihydro-1,3-benzoxazole rings and the phenyl ring are almost parallel to each other, making a dihedral angle of 5.30 (18)°, but they are almost normal to the mean plane of the other nine-membered 2,3-dihydro-1,3-benzoxazole ring, subtending dihedral angles of 89.29 (16) and 85.41 (18)°, respectively. The crystal structure features C - H...O hydrogen bonds and π-π stacking interactions [centroid-to-centroid distances = 3.5788 (19) Å, slippage = 0.438 and 3.7773 (16) Å, and slippage = 0.716 Å].
Crystal Structure and Vibrational Spectra of 3-Chloro-4-Phenyl-6-(Morpholine-4-yl)-Pyridazine by Hartree-Fock and Density Functional Methods
(2015-01-02) Aydin A.; Arslan H.; Şüküroʇlu M.; Akkurt M.; Büyükgüngör O.
The title compound, 3-chloro-4-phenyl-6-(morpholine-4-yl)-pyridazine (I), was prepared and characterized using elemental analysis and FT-IR and 1H NMR spectroscopy studies. The crystal and molecular structure of the title compound was determined from single-crystal X-ray diffraction data. It crystallizes in the orthorhombic space group P212121, Z = 8 with a = 7.5743 (3) Å, b = 14.8922 (8) Å, c = 23.3472 (9) Å, V = 2633.5 (2) Å3, and Dx = 1.391 Mg/m3. The title compound, C14H14ClN3O, crystallizes with two independent molecules A and B in the asymmetric unit, wherein the morpholine ring adopts a distorted chair conformation. The 1,6-dihydropyridazine ring creates dihedral angles of 47.0(3)° (in molecule A) and 47.9(2)° (in molecule B) with the phenyl ring, respectively. The crystal studied was an inversion twin with a 0.56(12):0.44(12) domain ratio. The molecular structure, vibrational frequencies, and intensities of the title compound were calculated using Hartree-Fock and density functional theory methods (BLYP, B3LYP, B3PW91, and mPW1PW91) using the 6-31G(d,p) basis set. The calculated geometric parameters were compared to the corresponding single crystal X-ray structure of the title compound. Comparison of the theoretical and experimental geometries of the title compound show that the X-ray parameters are in good agreement with the optimized molecular structure of the title compound. In addition, the harmonic vibrations computed for this compound using the B3LYP/6-31G(d,p) method are in good agreement with the observed vibrational spectral data. Theoretical vibrational spectra of the title compound were interpreted using PEDs and the VEDA 4 program. The superior performance of these investigated methods was calculated using the PAVF 1.0 program. © 2015
Crystal structure of (E)-2-({4-hydroxy-5-methoxy-3-[(4-methyl-1-piperazinyl)methyl]phenyl} methylidene)-1-indanone, C23H26N2O3
(2017-01-01) Tugrak M.; Aydin A.; Gul H.; Sahin E.; Akkurt M.
C23H26N2O3, triclinic, P1 (No. 2), a = 10.6646(19) Å, b = 10.7784(17) Å, c = 11.150(2) Å, α = 67.787(7)°, β = 64.309(7)°, γ = 64.271(7)°, V = 1011.6(3) Å3, Z = 2, Rgt(F) = 0.0502, wRref(F2) = 0.1481, T = 293 K.
Crystal structure of 1-{4-hydroxy-3-[(pyrrolidin-1-yl)methyl]phenyl}-3-phenylprop-2-en-1-one
(2016-05-01) Aydin A.; Akkurt M.; Gul H.; Yerdelen K.; Celik R.
In the title compound, C20H21NO2, the pyrrolidine ring adopts an envelope conformation with the N atom at the flap position. The central benzene ring makes dihedral angles of 21.39(10) and 80.10(15)° with the phenyl ring and the mean plane of the pyrrolidine ring, respectively. The molecular conformation is stabilized by an intramolecular O - H⋯N hydrogen bond, which closes an S(6) ring. A weak C - H⋯π interaction is observed in the crystal.
Crystal structure of 3-(p-bromobenzoyl)-4-(p-bromophenyl)-1-isopropyl-4- piperidinol hydrochloride, C21H24Br2ClNO 2
(2013-10-25) Aydin A.; Akkurt M.; Gul H.; Mete E.; Sahin E.
(Equation presentation) (Table presentation) Source of material Themixture of suitable ketone, paraformaldehyde and isopropylamine hydrochloride in 2:2:1 mol ratios was stirred and heated without solvent in an oil bath. Mono Mannich base, namely 1-pbromophenyl- 3-isopropylamino-1-propanone hydrochloride, and a piperidinol type compound, namely 3-(p-bromobenzoyl)- 4-(p-bromophenyl)-1- isopropylamino-4-piperidinol hydrochloride were produced in the reaction medium at the same time. Corresponding mono Mannich base of the title compound produced in the reactionmedium was removed from the reactionmedium to obtain the title compound. Solution of NaOH (5%) was added on residue. Reaction content was stirred at water bath at 313 K. Stirring was continued for 48 h observing the solidification of oily residue. Purification by crystallization from chloroform-hexane gave a white solid, yield 14 %, m.p. 485-487 K). Although solution of NaOH %5 was used, the elemental analysis result suggested that the salt with N-protonation was obtained. This information was confirmed by X Ray study. [Yield: 14 %, m.p.: 485-487 K]. 1H NMR (400 MHz, CDCl3, ppm) δ 1.44 (d, J = 6.6 Hz, 3H), 1.53 (d, J = 6.6 Hz, 3H), 1.94 (br d, J = 14.3 Hz, 1H), 2.84-2.91 (m, 1H), 3.31-3.51 (m, 5H), 5.01 (d, J = 2.6 Hz, 1H, OH), 5.78 (dd, J = 12.1, 3.7 Hz, 1H), 7.36 (d, J = 8.4 Hz, 2H), 7.43 (d, J = 8.4 Hz, 2H), 7.61 (d, J = 8.4 Hz, 2H), 8.02 (d, J = 8.4 Hz, 2H); 13C NMR (100 MHz, CDCl3, ppm) δ 16.3, 17.6, 36.4, 43.7, 46.1, 47.7, 58.5, 72.2, 122.0, 126.6, 130.9, 131.3, 132.0, 132.3, 133.0, 143.2, 201.2; MS (EI) m/z: 482.4; IR (KBr,cm-1): 1675 (CO). Calcd. for C21H24Br2ClNO2 (517.68): C, 48.72; H, 4.67; N, 2.71. Found: C, 48.74; H, 4.70; N, 2.83. (Table presentation) Discussion The piperidinium ring (N1/C4-C8), (Fig.1), adopts a chair conformation with the puckering parameters [1] of QT = 0.593(4) Å, θ = 174.4(4)°, φ = 179(4)°. The dihedral angle between the benzene rings (C9-C14 and C16-C21) is 61.4(2)°. The O1-C15-C7-C6, O2-C6-C7-C15, C1-C2-N1-C8 and C3-C2-N1-C8 torsion angles are -74.3(5), -56.0(5), 159.8(4) and -74.4(5)°, respectively. The Br-C1 bond lengths are 1885(5) and 1.895(5) Å and the C6-O2 bond length is 1.429(5) Å. The C11-C12-Br1 and C9-C6-O2 bond angles are 119.2(4)° and 107.7(3)°, respectively. The values are in agreement with those in [2] (1.904(2) Å, 1.416(2) Å and 119.66(14)°, 105.76(14)°), respectively. An intramolecular O-H...O hydrogen bond forms a pseudo six-membered ring with S(6) ring motif [3]. The chloride counter anion is connected to the protonated nitrogen atom by a medium strong hydrogen bond. (Table presentation).
Crystal structure of 3-(thiophen-2-yl-carbonyl)-4-(thiophen-2-yl)-1- isopropyl-4-piperidinol, C17H21NO2S2
(2013-10-25) Aydin A.; Akkurt M.; Gul H.; Mete E.; Sahin E.
(Equation presentation) (Table presentation) Source of material A mixture of a suitable ketone, paraformaldehyde and isopropylamine hydrochloride in the 2:2:1 ratio was stirred and heated without solvent in an oil bath. Mono Mannich base type, namely 1-(thiophen-2-yl)-3-isopropylamino-1-propanone hydrochloride, and a piperidinol type compound, namely 3-(thiophen-2-ylcarbonyl)- 4-(thiophen-2-yl)-1-isopropylamino-4-piperidinol hydrochloride were produced in the reaction medium at the same time. Corresponding mono Mannich base of the title compound produced in the reaction medium together with the title compound was removed from the reaction. A solution of NaOH (5%) was added on the residue. The reaction content was stirred at water bath at 313 K. Stirring was continued for 48 h observing the solidification of oily residue. Compound (I) was purified by crystallization from methanol-ether. [Yield: 11 %, mp.: 416-417 K]. 1H-NMR (400 MHz, CDCl3, ppm) δ: 1.09 (d, J = 6.2 Hz, 6H), 2.00-2.05 (m, 2H), 2.75-2.98 (m, 5H), 4.04 (br d, J = 8.8 Hz, 1H), 5.44 (s, 1H, OH), 6.82 (dd, J = 4.6, 3.3Hz, 1H), 6.91 (br d, J = 3.3 Hz, 1H), 7.07 (d, J = 4.6 Hz, 1H), 7.12 (dd, J = 4.8, 3.7 Hz, 1H), 7.67 (d, J = 4.8 Hz, 1H), 7.80 (d, J = 3.7 Hz, 1H); 13C-NMR (100 MHz, CDCl3, ppm) δ: 18.6, 18.8, 41.6, 44.4, 49.1, 54.4, 54.9, 72.9, 122.2, 123.9, 127.0, 128.8, 133.5, 135.8, 143.8, 153.4, 196.9; MS (EI) m/z: 335.2; IR (KBr,cm-1): 1635 (CO). Calcd. for C17H21NO2S2 (335.48): C, 60.86; H, 6.31; N, 4.18; S, 19.12. Found: C, 60.55; H, 6.55; N, 4.18; S, 19.47. Experimental details All H atoms were positioned geometrically and treated as riding on their parent atoms, with O-H = 0.82 (hydroxyl), C-H = 0.93 (aromatic), 0.97 Å (methylene), respectively, and with Uiso(H) = 1.5Ueq(C, O) for methyl and hydroxyl andUiso(H) = 1.2Ueq(C) for the others. One of the two thiophene rings is disordered over two positions, corresponding to rotation of approximately 180° about the single C-C bond, with site occupancy factors of 0.676(3) and 0.324(3). The atoms of the isopropyl group are also disordered over two positions [occupancies = 0.605(8):0.395(8)]. Discussion In the title structure (Fig.) the piperidine ring (N1/C6-C10) adopts a chair conformation which is evident from the puckering parameters [1]: QT= 0.585(4) Å, θ = 178.0(4)° and φ = 162(10)°, respectively. The plane of the thiophene ring (S1/C1-C4) makes dihedral angles of and 81.9(3)° and 79.0(6)°, respectively, with the planes of the major and minor components (S2A/C11/C12A-C14A and S2B/C11/C12B-C14B) of the disordered thiophene ring, while these disordered thiophene rings form a dihedral angle of 8.0(6)° with each other. The bond lengths and angles are within normal ranges and comparable with those observed in the similar structures [2]. The C14A-S2A and C1-S1 bond lengths are 1.690(8) Å, and 1.682(5) Å, respectively. The C14A-S2A-C11 and C1-S1-C4 bond angles are 93.0(3)° and 91.9(2)°, respectively and the values are in agreement with those in [3] (1.697(2) Å, 1.704(2) Å and 93.6(1)°, 92.2(1)°), respectively. The molecular conformation is stabilized by intramolecular O2-H2A...O1 hydrogen bond, with a S(6) ring motif [4]. Semiempirical AM1 calculations of the title structure were carried out with WinMopac 7.2 software [5, 6]. The dihedral angle between the thiophene rings is 49.08° and is different from that in the x-ray result. The dipole moment, the HOMO and LUMO energy levels are calculated as about 2.530 Debye, -9.1202 and -0.0523 eV, respectively.Wemay state that the theoretical calcu- lation supports the suggestion that the present intra and intermolecular interactions influence the molecular geometry. (Table presentation).
Crystal structure of 3-{5-[(2-chlorophenyl)carbonyl]-2-oxo1,3-benzothiazol- 3(2H)-yl}propanoic acid, C17H12ClNO4S
(2010-10-07) Aydin A.; Akkurt M.; Önkol T.; Büyükgüngör O.
C17H12ClNO4S, monoclinic, Pl2 1/cl (no. 14), a = 13.1203(8) Å, b = 16.6201(9) Å,c = 7.7539(4) Å, β = 103.559(5)°, V= 1643.7 Å3, Z = 4, Rgt(F) = 0.046, wRref(F2) = 0.131, T=296 K. © by Oldenbourg Wissenschaftsverlag, München.
Crystal structure of 4-(4-chlorophenyl)-6-(morpholin-4-yl)pyridazin-3(2H)-one
(2015-01-01) Aydin A.; Akkurt M.; Şüküroǧlu M.; Büyükgüngör O.
In the title compound, C14H14ClN3O2, the morpholine ring adopts a chair conformation, with the exocyclic N-C bond in an equatorial orientation. The 1,6-dihydropyridazine ring is essentially planar, with a maximum deviation of 0.014 (1) Å, and forms a dihedral angle of 40.16 (7)° with the plane of the benzene ring. In the crystal, pairs of centrosymmetrically related molecules are linked into dimers via N-H···O hydrogen bonds, forming R22(8) ring motifs. The dimers are connected via C-H···O and C-H···Cl hydrogen bonds, forming a three-dimensional network. Aromatic π-π stacking interactions [centroid-centroid distance = 3.6665 (9) Å] are also observed. Semi-empirical molecular orbital calculations were carried out using the AM1 method. The calculated dihedral angles between the pyridizine and benzene rings and between the pyridizine and morpholine (all atoms) rings are 34.49 and 76.96°, respectively·The corresponding values obtained from the X-ray structure determination are 40.16 (7) and 12.97 (9)°, respectively. The morpholine ring of the title compound in the calculated gas-phase seems to have a quite different orientation compared to that indicated by the X-ray structure determination.
Crystal structure of methyl (6-(2-fluorobenzoyl)-5-chloro-2-benzoxazolinon-3-yl)-acetate, C17H11ClFNO5
(2006-04-01) Aydin A.; Diindar Y.; Akkurt M.; Büyükgüngör O.; Sahin M.F.
C17H11ClFNO5, monoclinic, P121/c1 (no. 14), a = 7.489(5) Å, b = 18.367(5) Å, c = 11.752(5) Å, β = 94.222(5)°, V = 1612.1 Å3, Z = 4, Rgt(F) = 0.032, wRref(F2) = 0.083, T = 293 K. © 2014 Oldenbourg Wissenschaftsverlag GmbH, Rosenheimer Str. 145, 81671 München. All rights reserved.
Methyl [6-(2-chlorobenzoyl)-2-oxo-2,3-dihydro-1,3-benzoxazol-3-yl]acetate
(2007-02-01) Aydin A.; Dündar Y.; Akkurt M.; Büyükgüngör O.; Şahin M.F.
In the molecular structure of the title compound, C17H 12ClNO5, the 1,3-benzoxazole ring system makes a dihedral angle of 72.96 (7)° with the benzene ring of the 2-chlorobenzoyl group. In the crystal structure, two intra-molecular C-H⋯O hydrogen bonds influence the molecular conformation. © 2007 International Union of Crystallography All rights reserved.