Search tips
Search criteria

Results 1-25 (473529)

Clipboard (0)

Related Articles

1.  6-{5-Amino-3-tert-butyl-4-[(E)-(3-methyl-1,2,4-thiadiazol-5-yl)diazen­yl]-1H-pyrazol-1-yl}-1,3,5-triazine-2,4(1H,3H)-dione–1-methyl­pyrrolidin-2-one–water (1/1/1) 
In the title compound, C13H16N10O2S·C5H9NO·H2O, the entire 1-methylpyrrolidin-2-one (NMP) mol­ecule is disordered over two sites with occupancies of 0.488 (5) and 0.512 (5). The six-membered triazine ring and the two five-membered pyrazole and thiadia­zole rings, together with the diazene (–N=N–) linkage are almost coplanar (r.m.s. deviation for the non-H atoms = 0.0256 Å) with methyl groups from the tert-butyl substituent on the pyrazole ring located above and below the plane. Three intra­molecular N—H⋯N hydrogen bonds contribute to the planarity of the system. The O atom of the NMP mol­ecule is hydrogen bonded to an O—H group of water. In turn, the water mol­ecule is hydrogen bonded to the mono-azo skeleton through inter­molecular N—H⋯O and O—H⋯N hydrogen bonds. At both ends of the long mol­ecular axis of the main mol­ecule there are inter­molecular N—H⋯N hydrogen bonds, arranged in a head-to-tail fashion, between the N—H group of the triazine ring of one mol­ecule and the N atom of the thia­diazole ring of a neighboring mol­ecule. These form a polymeric chain along [110] or [10]. The main mol­ecules are stacked alternately along the b axis, which effectively cancels their dipole moments. In addition, pairs of alternate molecules are dimerized via inter­molecular hydrogen bonds involving the solvent mol­ecules.
PMCID: PMC2983887  PMID: 21580749
2.  Tetra­kis(μ2-4-amino­benzoato)di-μ3-oxido-tetra­kis[dibutyl­tin(IV)] 
The mol­ecule of the title compound, [Sn4(C4H9)8(C7H6NO2)4O2], lies about an inversion centre and is a tetra­nuclear bis­(tetra­butyl­dicarboxyl­ato­distannoxane) complex containing a planar Sn4O2 core in which two μ3-oxide O atoms connect an Sn2O2 ring to two exocyclic Sn atoms. Each Sn atom has a highly distorted octa­hedral coordination. In the mol­ecule, the carboxyl­ate groups of two amino­benzoate ligands bridge the central and exocyclic Sn atoms, while two further amino­benzoate ligands have highly asymmetric bidentate chelation to the exocyclic Sn atoms plus long O⋯Sn inter­actions with the central Sn atoms. Each Sn atom is also coordinated by two pendant n-butyl ligands, which extend roughly perpendicular to the plane of the Sn4O10 core. Only one of the four unique hydrogen-bond donor sites is involved in a classic N—H⋯O hydrogen bond, and the resulting supra­molecular hydrogen-bonded structure is an extended two-dimensional network which lies parallel to the (100) plane and consists of a checkerboard pattern of four-connected mol­ecular cores acting as nodes. The amine groups not involved in the hydrogen-bonding inter­actions have significant N—H⋯π inter­actions with neighbouring amino­benzene rings.
PMCID: PMC2855585  PMID: 20203395
3.  (2,6-Bis{5-amino-3-tert-butyl-4-[(3-methyl-1,2,4-thia­diazol-5-yl)diazen­yl]-1H-pyrazol-1-yl}-4-oxo-1,4-dihydro-1,3,5-triazin-1-ido)methanol(phenol)sodium phenol tetra­solvate 
The title compound, [Na(C23H28N17OS2)(CH3OH)(C6H5OH)]·4C6H5OH, is a five-coordinate NaI complex. The Na+ cation is bound to three N atoms of the triazinide ligand, two from each pyrazole ring and one from the central deprotonated triazine ring system. O atoms from a methanol and a phenol mol­ecule complete the five-coordinate NaN3O2 coordination environment. The asymmetric unit also includes three complete and two half phenol mol­ecules, four of which are hydrogen bonded to the N atoms of the thia­diazole ring. Two of the phenol solvent mol­ecules are disordered over two discrete inversion centres. The triazinide ligand is essentially planar (mean deviation from the least-squares plane = 0.0524 Å), with the methyl groups of the tert-butyl substituents on the pyrazole rings located above and below the plane. The planarity of this system is further assisted by the formation of four intra­molecular N—H⋯N hydrogen bonds between the N—H bonds of both amino groups on the pyrazole rings and the N atoms of the triazine ring and also from each of the adjacent diazene (–N=N–) bonds. The highly polar mol­ecules are stacked along the a axis through the central Na atom sandwiched by two kinds of alternating inter­molecular hydrogen bonds: O(carbon­yl)⋯H—O(methanol)/Na/O—H(phenol)⋯O(carbon­yl). These inter­actions form two polymer chains per mol­ecule.
PMCID: PMC2983962  PMID: 21580548
4.  Crystal structure of 2-hy­droxy­imino-2-(pyridin-2-yl)-N′-[1-(pyridin-2-yl)ethyl­idene]acetohydrazide 
The mol­ecule of the title compound is approximately planar with the planes of the two pyridine rings inclined to one another by 5.51 (7)°. In the crystal, mol­ecules are linked by bifurcated O—H⋯(O,N) hydrogen bonds, forming inversion dimers, which are in turn linked via C—H⋯O and C—H⋯N hydrogen bonds, forming sheets lying parallel to (502).
The mol­ecule of the title compound, C14H13N5O2, is approximately planar (r.m.s deviation for all non-H atoms = 0.093 Å), with the planes of the two pyridine rings inclined to one another by 5.51 (7)°. The oxime group is syn to the amide group, probably due to the formation of an intra­molecular N—H⋯N hydrogen bond that forms an S(6) ring motif. In the crystal, mol­ecules are linked by pairs of bifurcated O—H⋯(O,N) hydrogen bonds, forming inversion dimers. The latter are linked via C—H⋯O and C—H⋯N hydrogen bonds, forming sheets lying parallel to (502). The sheets are linked via π–π stacking inter­actions [inter-centroid distance = 3.7588 (9) Å], involving the pyridine rings of inversion-related mol­ecules, forming a three-dimensional structure.
PMCID: PMC4257442  PMID: 25552998
crystal structure; hy­droxy­imino; acetohydrazide; pyridyl­ethyl­idene; hydrogen bonding; π–π stacking inter­actions
5.  2-tert-Butyl 4-methyl 3,5-dimethyl-1H-pyrrole-2,4-dicarboxyl­ate 
In the title mol­ecule, C13H19NO4, except for two C atoms of the tert-butyl group, the non-H atoms are almost coplanar (r.m.s. deviation = 0.2542 Å). In the crystal, mol­ecules are linked into centrosymmetric dimers by two inter­molecular N—H⋯O hydrogen bonds, forming an R 2 2(10) ring motif.
PMCID: PMC3379292  PMID: 22719490
6.  Poly[[tetra­aqua­bis­(μ3-1H-imidazole-4,5-dicarboxyl­ato)tetra­kis­(μ2-1H-imidazole-4,5-dicarboxyl­ato)tricobalt(II)diytterbium(III)] dihydrate] 
The asymmetric unit of the title compound, {[Co3Yb2(C5H2N2O4)6(H2O)4]·2H2O}n, contains one YbIII ion, two CoII ions (one situated on an inversion centre), three imidazole-4,5-dicarboxyl­ate ligands, two coordinated water mol­ecules and one uncoordinated water mol­ecule. The YbIII ion is seven-coordinated, in a monocapped trigonal prismatic coordination geometry, by six O atoms from three imidazole-4,5-dicarboxyl­ate ligands and one water O atom. Both CoII ions are six-coordinated in a slightly distorted octa­hedral geometry. The CoII ion that is located on an inversion center is coordinated by two O atoms from two water mol­ecules, as well as two O atoms and two N atoms from two imidazole-4,5-dicarboxyl­ate ligands. The second CoII ion is bonded to four O atoms and two N atoms from four imidazole-4,5-dicarboxyl­ate ligands. These metal coordination units are connected by bridging imidazole-4,5-dicarboxyl­ate ligands, generating a three-dimensional network. The crystal structure is further stabilized by N—H⋯O, O—H⋯O and C—H⋯O hydrogen-bonding inter­actions involving the water mol­ecules and the imidazole-4,5-dicarboxyl­ate ligands.
PMCID: PMC3212186  PMID: 22090888
7.  1-(2-Chloro-5-nitro­phen­yl)-3-(2,2-di­methyl­propion­yl)thio­urea 
With the exception of the C atoms of two of the methyl groups of the tert-butyl substituent, all of the non-H atoms of the title compound, C12H14ClN3O3S, lie on a mirror plane. The 2-chloro-5-nitro­phenyl and 2,2-dimethyl­propionyl substituents are, respectively, cis and trans relative to the thio­carbonyl S atom across the two C—N bonds. Intra­molecular N—H⋯O and C—H⋯S hydrogen bonds form S(6) ring motifs, also in the mirror plane. Despite the presence of two N—H subsituents, no inter­molecular hydrogen bonds are observed in the crystal structure. Weak π–π contacts [centroid–centroid distances of 4.2903 (17) Å] involving adjacent aromatic rings link the mol­ecules in a head-to-tail fashion above and below the mol­ecular plane.
PMCID: PMC2977335  PMID: 21583450
8.  4,6-Dimeth­oxy-2-(methyl­sulfan­yl)pyrimidine–4-hy­droxy­benzoic acid (1/1) 
The base mol­ecule of the title co-crystal, C7H10N2O2S·C7H6O3, is essentially planar, with a maximum deviation of 0.0806 (14) Å for all non-H atoms. The acid mol­ecule is also nearly planar, with a dihedral angle of 8.12 (14)° between the benzene ring and the carb­oxy group. In the crystal, the acid mol­ecules form an inversion dimer through a pair of O—H⋯O hydrogen bonds with an R 2 2(8) ring motif. The pyrimidine mol­ecules are linked on both sides of the dimer into a heterotetra­mer via O—H⋯N and C—H⋯O hydrogen bonds with R 2 2(8) ring motifs. The heterotetra­mers are further linked by weak C—H⋯O hydrogen bonds, forming a tape structure along [1-10].
PMCID: PMC3589001  PMID: 23476237
9.  Poly[tetra­deca­aqua­tetra­kis­(μ3-1H-imidazole-4,5-dicarboxyl­ato)tetra-μ3-sulfato-cobalt(II)hexa­gadolinium(III)] 
The asymmetric unit of the title compound, [CoGd6(C5H2N2O4)4(SO4)6(H2O)14]n, contains a CoII ion (site symmetry ), three GdIII ions, two imidazole-4,5-dicarboxyl­ate ligands, three SO4 2− anions, and seven coordinated water mol­ecules. The CoII ion is six-coordinated by two O atoms from water mol­ecules, two O atoms and two N atoms from two imidazole-4,5-dicarboxyl­ate ligands, giving a slightly distorted octa­hedral geometry. The GdIII ions exhibit three types of coordination environments. One Gd ion is eight-coordinated in a bicapped trigonal–prismatic geometry by four O atoms from two imidazole-4,5-dicarboxyl­ate ligands, two O atoms from two SO4 2− anions and two coordinated water mol­ecules. The other Gd ions are nine-coordinated in a tricapped trigonal–prismatic geometry; one of these Gd ions is bonded to four O atoms from two imidazole-4,5-dicarboxyl­ate ligands, three O atoms from three SO4 2− anions and two water O atoms and the other Gd ion is coordinated by one O atom and one N atom from one imidazole-4, 5-dicarboxyl­ate ligand, five O atoms from three SO4 2− anions as well as two coordinated water mol­ecules. These metal coordination units are connected by bridging imidazole-4,5-dicarboxyl­ate and sulfate ligands, generating a three-dimensional network. The crystal structure is further stabilized by N—H⋯O, O—H⋯O, and C—H⋯O hydrogen-bonding inter­actions between water mol­ecules, SO4 2− anions, and imidazole-4,5-dicarboxyl­ate ligands.
PMCID: PMC3212143  PMID: 22090845
10.  5-Chloro-N-(4,5-dihydro-1H-imidazol-2-yl)-2,1,3-benzothia­diazol-4-amine (tizanidine) 
There are two independent mol­ecules (A and B) with similar conformations in the asymmetric unit of the title compound, C9H8ClN5S. The benzothia­diazole ring systems of both mol­ecules are essentially planar [maximum deviation = 0.021 (2) Å in mol­ecule A and 0.022 (1) Å in mol­ecule B] and make dihedral angles of 68.78 (9) and 54.39 (8)°, respectively, with the mean planes of their 4,5-dihydro-1H-imidazole rings. An intra­molecular N—H⋯Cl hydrogen bond occurs in mol­ecule B. In the crystal, both mol­ecules form centrosymmetric dimers through π-stacking of their benzothia­diazole rings, with inter­planar distances of 3.3174 (7) and 3.2943 (6) Å. These dimers are further linked via pairs of N—H⋯N hydrogen bonds with the dihydro­imidazole rings as the hydrogen-bonding donors and one of the benzothia­diazole N atoms as the acceptors, generating R 2 2(16) ring motifs. The A 2 and B 2 dimers in turn form additional N—H⋯N hydrogen bonds with the secondary amine as the H-atom donor and the dihydro­imidazole N atom as the acceptor. These R 2 2(8)-type inter­actions connect the A 2 and B 2 dimers with each other, forming infinite chains along [11].
PMCID: PMC3100067  PMID: 21754121
11.  Ethyl 5-hy­droxy-6-oxo-4-phenyl-5,6-dihydro-4H-cyclo­penta­[b]thio­phene-5-carboxyl­ate 
In the title mol­ecule, C16H14O4S, the dihydro­cyclo­penta­thio­phenone ring system is almost planar, with an r.m.s. deviation of 0.060 Å from the best fit plane through all nine non-H atoms. The cyclo­penta­none ring adopts a severely flattened envelope conformation with the C atom carrying the OH and ethylcarboxylate substituents at the flap. This atom lies only 0.185 (3) Å from the plane through the other four C atoms. The phenyl substituent is inclined at 43.37 (5)° to the dihydro­cyclo­penta­thio­phenone mean plane. In the crystal, mol­ecules are linked by pairs of O—H⋯O hydrogen bonds, forming inversion dimers with R 2 2(10) ring motifs. Weak C—H⋯O hydrogen bonds also link mol­ecules into chains along c, while an approximately orthogonal set of C—H⋯O contacts form chains along b, resulting in layers lying parallel to (100). Inversion dimers also form through weaker R 2 2(12) C—H⋯S contacts, which combine with C—H⋯O contacts to form stacks along b.
PMCID: PMC3201281  PMID: 22058815
12.  N-tert-Butyl-3-hydr­oxy-5-androstene-17-carboxamide monohydrate 
In the title compound, C24H39NO2·H2O, the A and C rings of the pregnolene derivative sterol adopt chair conformations, with the B ring in a flattened chair conformation and the five-membered ring in an envelope conformation twisted about the C/D ring junction. The N-tert-butyl­carboxamide substituent is equatorial. The 3β-hydr­oxy H atom and one H atom of the water mol­ecule are disordered over two positions with equal occupancies. In the crystal structure, O—H⋯O hydrogen bonds between the 3β-hydr­oxy groups of neighbouring mol­ecules form dimers in the bc plane and these dimers are stacked along the a axis by additional O—H⋯O hydrogen bonds involving the water mol­ecules. The steric effect of the bulky tert-butyl substituent in the carboxamide chain precludes hydrogen-bond formation by the N—H group.
PMCID: PMC2969220  PMID: 21582804
13.  (E)-2-[1-(1-Benzothio­phen-2-yl)ethyl­idene]-N-phenyl­hydrazinecarboxamide 
The title compound, C17H15N3OS, crystallizes with two unique mol­ecules, denoted 1 and 2, in the asymmetric unit. The two mol­ecules are closely similar and overlay with an r.m.s. deviation of 0.053 Å. Both mol­ecules adopt E configurations with respect to the C=N bonds. The dihedral angles between the benzothio­phene groups and N-bound phenyl rings are 36.36 (9)° for mol­ecule 1 and 29.71 (9)° for mol­ecule 2. The C=N—NH—C(O)NH ethyl­idene–hydrazinecarboxamide units are also reasonably planar, with r.m.s. deviations of 0.061 and 0.056 Å, respectively, for the two mol­ecules. The methyl substituents lie 0.338 (3) and 0.396 (3) Å, respectively, from these planes. The C=N—NH—C(O)NH planes are inclined to the phenyl rings at 13.65 (11) and 15.56 (11)°, respectively, in mol­ecules 1 and 2. This conformation is enhanced by weak intra­molecular C—H⋯O hydrogen bonds between ortho-H atoms of the two phenyl rings and the carbonyl O atoms, which generate S(6) rings in each mol­ecule. In the crystal, pairs of mol­ecules are linked by pairs of inter­molecular N—H⋯O hydrogen bonds into dimers. Alternating dimers are further inter­connected by weak C—H⋯O contacts into zigzag rows along b. The rows are stacked along a by C—H⋯π contacts involving the benzene ring from molecule 2 and the thiophene ring from molecule 1 of adjacent benzothio­phene units.
PMCID: PMC3201294  PMID: 22058789
14.  4,4′-[Ethylenebis(nitrilomethylidyne)]dibenzonitrile 
The mol­ecule of the title Schiff base compound, C18H14N4, lies across a crystallographic inversion centre and adopts an E configuration with respect to the azomethine (C=N) bonds. The imino groups are coplanar with the aromatic rings with a maximum deviation of 0.1574 (12) Å for the N atom. Within the mol­ecule, the planar units are parallel, but extend in opposite directions from the dimethyl­ene bridge. In the crystal structure, pairs of inter­molecular C—H⋯N hydrogen bonds link neighbouring mol­ecules into centrosymmetric dimers with R 2 2(10) ring motifs. An inter­esting feature of the crystal structure is the short inter­molecular C⋯C inter­action with a distance of 3.3821 (13) Å, which is shorter than the sum of the van der Waals radius of a carbon atom.
PMCID: PMC2969074  PMID: 21582425
15.  3′-[(1H-Indol-3-yl)carbon­yl]-1′-methyl-2-oxo-4′-(thio­phen-2-yl)­spiro­[indoline-3,2′-pyrrolidine]-3′-carbo­nitrile 
In the title compound, C26H20N4O2S, the central pyrrolidine ring adopts a twist conformation on the C—C bond involving the spiro C atom. Its mean plane makes dihedral angles of 78.83 (14), 65.91 (15) and 44.49 (18)° with the mean planes of the adjacent oxindole ring system, the indole system and the thio­phene ring, respectively. The indole and indoline units are essentially planar, with maximum deviations of 0.019 (3) and 0.090 (3) Å, respectively. In the oxindole fused-ring system, the pyrrole ring adopts an envelope conformation with the spiro C atom as the flap. In the crystal, pairs of N—H⋯O hydrogen bonds link the mol­ecules, forming inversion dimers with an R 2 2(8) ring motif. The dimers are linked by further N—H⋯O hydrogen bonds, forming a two-dimensional network lying parallel to (100).
PMCID: PMC3790442  PMID: 24098261
16.  2-Amino-5-methyl­pyridinium 1H-pyrazole-3,5-dicarboxyl­ate trihydrate 
In the title compound, 2C6H9N2 +·C5H2N2O4 2−·3H2O, the 1H-pyrazole-3,5-dicarboxyl­ate anion is close to planar [maximum deviation = 0.208 (1) Å]. The two distinct 2-amino-5-methyl­pyridinium cations are also almost planar, with maximum deviations of 0.018 (2) and 0.014 (2) Å. In the crystal, pairs of inter­molecular N—H⋯O and O—H⋯O hydrogen bonds connect neighbouring mol­ecules into dimers, generating R 2 2(8) and R 2 4(8) ring motifs, respectively. Further inter­molecular N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network.
PMCID: PMC3008987  PMID: 21589058
17.  4-(But-3-enylamino)-3-nitro­benzoic acid 
The asymmetric unit of the title compound, C11H12N2O4, contains 12 crystallographically independent mol­ecules, labelled A to L. The nitro and carboxyl groups are twisted slightly out of the plane of the attached benzene ring in all independent mol­ecules except mol­ecules G and D. The nitro group is coplanar with the benzene ring in mol­ecule G and the carboxyl group is coplanar with the benzene ring in mol­ecule D. The orientation of the butyl group with respect to the rest of the mol­ecule is different in some of the independent mol­ecules, with the C—C—C—C torsion angles varying from 104.2 (5) to 126.6 (7)°. In each independent mol­ecule, an intra­molecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal structure, the 12 independent mol­ecules exist as six pairs of O—H⋯O hydrogen-bonded R 2 2(8) dimers. In addition, C—H⋯O hydrogen bonds are observed.
PMCID: PMC2969436  PMID: 21582843
18.  (2Z,2′Z)-Diethyl 3,3′-[butane-1,4-diylbis(aza­nedi­yl)]bis­(but-2-enoate) 
The whole mol­ecule of the title β-enamino­ester, C16H28N2O4, is generated by a crystallographic inversion center, situated at the mid-point of the central C—C bond of the 1,4-diamino­butane segment. There are two intra­molecular N—H⋯O hydrogen bonds that generate S(6) ring motifs. This leads to the Z conformation about the C=C bonds [1.3756 (17) Å]. The mol­ecule is S-shaped with the planar central 1,4-diamino­butane segment [maximum deviation for non H-atoms = 0.0058 (13) Å] being inclined to the ethyl butyl­enonate fragment [C—C—O—C—C=C—C; maximum deviation = 0.0710 (12) Å] by 15.56 (10)°. In the crystal, mol­ecules are linked via C—H⋯O inter­actions, leading to the formation of an undulating two-dimensional network lying parallel to the bc plane.
PMCID: PMC3470214  PMID: 23125658
19.  N-{2-[(4S)-4-tert-Butyl-4,5-dihydro-1,3-oxazol-2-yl]phen­yl}-5,6-diphenyl-1,2,4-triazin-3-amine 
The title compound, C28H27N5O, was synthesized using palladium cross-coupling amination of 3-bromo-5,6-diphenyl-1,2,4-triazine with 2-[(4S)-4-tert-butyl-4,5-dihydro-1,3-oxazol-2-yl]aniline. The oxazoline ring is almost planar, with a maximum atomic deviation of 0.023 (5) Å. The phenyl rings make dihedral angles of 29.0 (1) and 54.6 (1)° with the triazine ring while the benzene ring makes a dihedral angle of 0.6 (1)° with the oxazoline ring. The conformation of the mol­ecule is influenced by strong intra­molecular N—H⋯N and weak C—H⋯N hydrogen bonds. In the crystal, screw-axis related mol­ecules are linked into supra­molecular chains by inter­molecular C—H⋯O hydrogen bonds. π–π stacking is observed between the oxazoline and triazine rings of adjacent mol­ecules, with a centroid–centroid distance of 3.749 (2) Å.
PMCID: PMC3052057  PMID: 21522403
20.  5,8-Bis[bis­(pyridin-2-yl)amino]-1,3,4,6,7,9,9b-hepta­aza­phenalen-2(1H)-one dimethyl sulfoxide monosolvate dihydrate 
In the asymmetric unit of the title compound, C26H17N13O·C2H6OS·2H2O, there is one independent hepta­zine-based main mol­ecule, one dimethyl sulfoxide mol­ecule and two water mol­ecules as solvents. The tri-s-triazine unit is substituted with two dipyridyl amine moieties and a carbonylic O atom. As indicated by the bond lengths in this acid unit of the hepta­zine derivative [C=O = 1.213 (2) Å, while the adjacent C—N(H) bond = 1.405 (2) Å] it is best described by the keto form. The cyameluric nucleus is close to planar (r.m.s. deviation = 0.061 Å) and the pyridine rings are inclined to its mean plane by dihedral angles varying from 47.47 (5) to 70.22 (5)°. The host and guest mol­ecules are connected via N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds, forming a four-membered inversion dimer-like arrangement enclosing an R 4 4(24) ring motif. These arrangements stack along [1-10] with a weak π–π inter­action [inter-centroid distance = 3.8721 (12) Å] involving adjacent pyridine rings. There are also C—H⋯N and C—H⋯O hydrogen bonds and C—H⋯π inter­actions present within the host mol­ecule and linking inversion-related mol­ecules, forming a three-dimensional structure.
PMCID: PMC3998556  PMID: 24826156
21.  6-Amino-8-(2-bromo­phen­yl)-1,7,8,8a-tetrahydro-3H-isothio­chromene-5,7,7-tricarbonitrile dimethyl­formamide solvate 
In the title compound, C18H13BrN4S·C3H7NO, the thio­pyran ring and the adjacent six-numbered ring adopt distorted boat conformations. The mol­ecules, lying about inversion centers, form hydrogen-bonded dimers involving one of the H atoms on the amino group with the N atom of a cyano group of an adjacent mol­ecule, resulting in a 12-membered ring system [R 2 2(12) ring motif]. The other H atom of the amino group forms an inter­molecular hydrogen bond with the O atom of the dimethyl­formamide (DMF) mol­ecule. Another lone pair of electrons on the same carbonyl O atom of DMF mol­ecule forms a non-classical C—H⋯O inter­molecular hydrogen bond, resulting in a chain of mol­ecules.
PMCID: PMC2971116  PMID: 21578244
22.  n-Butyl­dichlorido(2-{(1E)-1-[2-(pyridin-2-yl)hydrazin-1-yl­idene]eth­yl}phenolato)tin(IV) 
Two independent mol­ecules comprise the asymmetric unit of the title compound, [Sn(C4H9)(C13H12N3O)Cl2]. The Sn atom in each is coordinated by the tridentate ligand via the phenoxide O, hydrazine N and pyridyl N atoms, forming five- and six-membered chelate rings. The approximately octa­hedral coordination geometry is completed by the α-C atom of the n-butyl group (which is trans to the hydrazine N atom) and two mutually trans Cl atoms. Differences between the mol­ecules are evident in the relative planarity of the chelate rings and in the conformations of the n-butyl groups [C—C—C—C = 177.2 (5) and −64.4 (11)°]. Significant differences in the Sn—Cl bond lengths are related to the formation of N—H⋯Cl hydrogen bonds, which link the mol­ecules comprising the asymmetric unit into dimeric aggregates. These are consolidated in the crystal packing by C—H⋯Cl contacts. The structure was refined as an inversion twin; the minor twin component is 37 (3)%.
PMCID: PMC3009310  PMID: 21588842
23.  1-(2-Chloro­phen­yl)-3-(2-ethyl­hexa­noyl)thio­urea 
In the title compound, C15H21ClN2OS, the central chromophore moiety (C2N2OS) is approximately planar, with a maximum deviation of −0.027 (1) Å, and is oriented at a dihedral angle of 86.7 (1)° with respect to the chloro­phenyl ring. An intra­molecular N—H⋯O hydrogen bond stabilizes the mol­ecular conformation. In the crystal, mol­ecules associate via N—H⋯S hydrogen bonds, forming inversion dimers with motif R 2 2(8). These dimers are further connected by N—H⋯O hydrogen bonds, forming R 2 2(12) dimers. As a result, hydrogen-bonded chains running along [110] are formed. C—H⋯S inter­actions also occur. The terminal two C atoms of the butyl chain are disordered over two positions with an occupancy ratio of 0.54:0.46.
PMCID: PMC3793726  PMID: 24109313
24.  (1Z,2E)-N′-{1-[2-(4-Bromo­phen­yl)hydrazin-1-yl­idene]-1-chloro­propan-2-yl­idene}thio­phene-2-carbohydrazide 
In the title compound, C14H12BrClN4OS, the thienyl ring is disordered over two orientations with a site-occupancy ratio of 0.853 (2):0.147 (2). The mol­ecule is roughly planar, with the dihedral angles between the thienyl and benzene rings being 6.24 (16) and 9.7 (11)° for the major and minor components, respectively. The central fragment is almost planar [r.m.s. deviation = 0.0275 (2) Å for the ten non-H atoms]. The mean plane through this middle unit makes a dihedral angle of 2.71 (7)° with the benzene ring, whereas these values are 4.46 (15) and 7.7 (11)° for the major and minor components of the thienyl ring, respectively. In the crystal, mol­ecules are linked into dimers by pairs of N—H⋯O hydrogen bonds, forming R 2 2(8) ring motifs. These dimers are arranged into sheets parallel to the ac plane.
PMCID: PMC3344617  PMID: 22590379
25.  Bis[4-(4-pyridyl)pyridinium] μ-4,4′-bipyridine-bis­[tetra­aqua­(4,4′-bipyridine)manganese(II)] bis­(5-sulfonatobenzene-1,3-dicarboxyl­ate) 4,4′-bipyridine solvate penta­deca­hydrate 
The crystal structure of the title compound, (C10H9N2)2[Mn2(C10H8N2)3(H2O)8](C8H3O7S)2·C10H8N2·15H2O, consists of dinuclear MnII complex cations, sulfonato­benzene­dicarboxyl­ate trianions, 4-(4-pyridyl)pyridinium cations, uncoordin­ated 4,4′-bipyridine and uncoordinated water mol­ecules. One 4,4′-bipyridine mol­ecule bridges two Mn atoms, forming a centrosymmetric dinuclear complex; the mid-point of the C—C bond linking the pyridine rings of the bridging ligand is located on an inversion center. Each MnII atom is coordinated by four water and two 4,4′-bipyridine mol­ecules in a distorted octa­hedral geometry. The MnII atom deviates by 0.591 (5) and 0.209 (2) Å from the mean planes of the coordinated pyridine rings. In the 4-(4-pyridyl)pyridinium cation, the two pyridine rings are twisted with respect to each other, making dihedral angle of 34.78 (17)°. The uncoordinated bipyridine mol­ecule is also centrosymmetric. One of uncoordinated water mol­ecules has site symmetry 2, and the other uncoordinated water mol­ecule is located close to an inversion center and its one H atom is disordered equally over two sites. Extensive π–π stacking between pyridine rings is observed and an extensive hydrogen-bonding network of the types N—H⋯N, O—H⋯N and O—H⋯O is present.
PMCID: PMC2977419  PMID: 21583419

Results 1-25 (473529)