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1.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 10): 183-7, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25484647

RESUMEN

The structures of the co-crystalline adducts of 3,5-di-nitro-benzoic acid (3,5-DNBA) with 4-amino-salicylic acid (PASA), the 1:1 partial hydrate, C7H4N2O6·C7H7NO3·0.2H2O, (I), and with 2-hy-droxy-3-(1H-indol-3-yl)propenoic acid (HIPA), the 1:1:1 d (6)-dimethyl sulfoxide solvate, C7H4N2O6·C11H9NO3·C2D6OS, (II), are reported. The crystal substructure of (I) comprises two centrosymmetric hydrogen-bonded R 2 (2)(8) homodimers, one with 3,5-DNBA, the other with PASA, and an R 2 (2)(8) 3,5-DNBA-PASA heterodimer. In the crystal, inter-unit amine N-H⋯O and water O-H⋯O hydrogen bonds generate a three-dimensional supra-molecular structure. In (II), the asymmetric unit consists of the three constituent mol-ecules, which form an essentially planar cyclic hydrogen-bonded heterotrimer unit [graph set R 3 (2)(17)] through carboxyl, hy-droxy and amino groups. These units associate across a crystallographic inversion centre through the HIPA carb-oxy-lic acid group in an R 2 (2)(8) hydrogen-bonding association, giving a zero-dimensional structure lying parallel to (100). In both structures, π-π inter-actions are present [minimum ring-centroid separations = 3.6471 (18) Šin (I) and 3.5819 (10) Šin (II)].

2.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 11): 294-7, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25484726

RESUMEN

The structures of the 1:1 co-crystalline adduct C8H6BrN3S·C7H5NO4, (I), and the salt C8H7BrN3S(+)·C7H3N2O7 (-), (II), obtained from the inter-action of 5-(4-bromo-phen-yl)-1,3,4-thia-diazol-2-amine with 4-nitro-benzoic acid and 3,5-di-nitro-salicylic acid, respectively, have been determined. The primary inter-species association in both (I) and (II) is through duplex R (2) 2(8) (N-H⋯O/O-H⋯O) or (N-H⋯O/N-H⋯O) hydrogen bonds, respectively, giving heterodimers. In (II), these are close to planar [the dihedral angles between the thia-diazole ring and the two phenyl rings are 2.1 (3) (intra) and 9.8 (2)° (inter)], while in (I) these angles are 22.11 (15) and 26.08 (18)°, respectively. In the crystal of (I), the heterodimers are extended into a chain along b through an amine N-H⋯Nthia-diazole hydrogen bond but in (II), a centrosymmetric cyclic hetero-tetra-mer structure is generated through N-H⋯O hydrogen bonds to phenol and nitro O-atom acceptors and features, together with the primary R (2) 2(8) inter-action, conjoined R (4) 6(12), R (2) 1(6) and S(6) ring motifs. Also present in (I) are π-π inter-actions between thia-diazole rings [minimum ring-centroid separation = 3.4624 (16) Å], as well as short Br⋯Onitro inter-actions in both (I) and (II) [3.296 (3) and 3.104 (3) Å, respectively].

3.
Acta Crystallogr C ; 69(Pt 9): 1034-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24005516

RESUMEN

The crystal structures of the anhydrous products from the interaction of 5-(4-bromophenyl)-1,3,4-thiadiazol-2-amine with 2-(naphthalen-2-yloxy)acetic acid, viz. the 1:1 adduct C8H6BrN3S·C12H10O3, (I), and with 3,5-dinitrobenzoic acid, viz. the salt 2-amino-5-(4-bromophenyl)-1,2,4-thiadiazol-3-ium 3,5-dinitrobenzoate, C8H7BrN3S(+)·C7H3N2O6(-), (II), have been determined. In adduct (I), a heterodimer is formed through a cyclic hydrogen-bonding motif [graph set R2(2)(8)], involving carboxylic acid-heteroatom O-H···N and amine-carboxylic acid N-H···O interactions. The heterodimers are essentially planar, with a thiadiazole-to-naphthalene ring dihedral angle of 15.9 (2)° and an intramolecular thiadiazole-to-benzene ring angle of 4.7 (2)°. An amine-heteroatom N-H···N hydrogen bond between the heterodimers generates a one-dimensional chain structure extending down [001]. Also present are weak benzene-benzene and naphthalene-naphthalene π-π stacking interactions down the b axis [minimum ring-centroid separation = 3.936 (3) Å]. With salt (II), the cation-anion association is also through a cyclic R2(2)(8) motif but involving duplex N-H···O(carboxylate) hydrogen bonds, giving a heterodimer that is close to planar [dihedral angles between the thiadiazole ring and the two benzene rings = 5.00 (16) (intra) and 7.23 (15)° (inter)]. A secondary centrosymmetric cyclic RR4(2)(8) N-H···O(carboxylate) hydrogen-bonding association involving the second amino H atom generates a heterotetramer. Also present in the crystal structure are weak π-π interactions between thiadiazolium rings [minimum ring-centroid separation = 3.9466 (18) Å], as well as a short Br···O(nitro) interaction [3.314 (4) Å]. The two structures reported here now provide a total of three crystallographically characterized examples of cocrystalline products from the interaction of 5-(4-bromophenyl)-1,3,4-thiadiazol-2-amine with carboxylic acids, of which only one involves proton transfer.


Asunto(s)
Ácidos Naftalenoacéticos/química , Nitrobenzoatos/química , Sales (Química)/química , Tiadiazoles/química , Cristalografía por Rayos X , Enlace de Hidrógeno , Estructura Molecular
4.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 5): o786-7, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23723930

RESUMEN

In the title squaraine dye solvate, C26H24N2O2·2CHCl3, the dye mol-ecule is essentially planar, except for the methyl groups, having a maximum deviation over the 26-membered delocalized bond system of 0.060 (2) Å. It possesses crystallographic twofold rotational symmetry with the indole ring systems adopting a syn conformation. The mol-ecular structure features intra-molecular N-H⋯O hydrogen bonds enclosing conjoint S7 ring motifs about one of the dioxo-cyclo-butene O atoms, while the two chloro-form solvent mol-ecules are linked to the second O atom through C-H⋯O hydrogen bonds.

5.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): o835-6, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23795025

RESUMEN

In the crystal of the title hydrated mol-ecular salt, C8H12NO(+)·Cl(-)·H2O, the water mol-ecule makes two O-H⋯Cl hydrogen bonds, generating [010] zigzag chains of alternating water mol-ecules and chloride ions. The cation is bonded to the chain by an O-H⋯O hydrogen bond and two weak C-H⋯Cl inter-actions. Weak aromatic π-π stacking [centroid-centroid separation = 3.5175 (15) Å] occurs between the chains.

6.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): o884, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23795060

RESUMEN

In the cation of the title salt, C8H11N2 (+)·Br(-), the dihedral angle between the planes of the pyridinium ring and the allyl group is 79.4 (3)°. In the crystal, N-H⋯Br and weak C-H⋯Br hydrogen bonds link the cations and anions, forming chains of alternating R 2 (1)(7) and R 4 (2)(8) rings, which run parallel to the c-axis direction. The crystal studied was an inversion twin with components in a 0.753 (12):0.247 (12) ratio.

7.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): o941-2, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23795105

RESUMEN

The title salt, C8H12NO(+)·Br(-)·H2O, is isomorphous with the chloride analogue [Seethalakshmi et al. (2013). Acta Cryst. E69, o835-o836]. In the solid state, the cations, anions and water mol-ecules are inter-linked by a network of O-H⋯O, O-H⋯Br and C-H⋯Br inter-actions. The water mol-ecule makes two O-H⋯Br hydrogen bonds, generating [010] zigzag chains of alternating water mol-ecules and bromide anions. The cation is involved in two inter-molecular C-H⋯Cl inter-actions in the chloride salt, whereas three inter-molecular C-H⋯Br inter-actions are observed in the title bromide salt. This additional inter-molecular C-H⋯Br inter-action links the adjacent water and bromide zigzag chains via cationic mol-ecules. In addition, weak π-π stacking inter-actions are observed between pyridinium rings [centroid-centroid distance = 3.5664 (13) Å].

8.
Acta Crystallogr C ; 66(Pt 7): o324-8, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20603557

RESUMEN

In 2,4-diamino-6-methyl-1,3,5-triazin-1-ium (acetoguanaminium) hydrogen phthalate, C(4)H(8)N(5)(+) x C(8)H(5)O(4)(-), (I), acetoguanaminium hydrogen maleate, C(4)H(8)N(5)(+) x C(4)H(3)O(4)(-), (II), and acetoguanaminium 3-hydroxypicolinate monohydrate, C(4)H(8)N(5)(+) x C(6)H(4)NO(3)(-) x H(2)O, (III), the acetoguanaminium cations interact with the carboxylate groups of the corresponding anions via a pair of nearly parallel N-H...O hydrogen bonds, forming R(2)(2)(8) ring motifs. In (II) and (III), N-H...N base-pairing is observed, while there is none in (I). In (II), a series of fused R(3)(2)(8), R(2)(2)(8) and R(3)(2)(8) hydrogen-bonded rings plus fused R(2)(2)(8), R(6)(2)(12) and R(2)(2)(8) ring motifs occur alternately, aggregating into a supramolecular ladder-like arrangement. In (III), R(2)(2)(8) motifs occur on either side of a further ring formed by pairs of N-H...O hydrogen bonds, forming an array of three fused hydrogen-bonded rings. In (I) and (II), the anions form a typical intramolecular O-H...O hydrogen bond with graph set S(7), whereas in (III) an intramolecular hydrogen bond with graph set S(6) is formed.


Asunto(s)
Maleatos/química , Ácidos Ftálicos/química , Ácidos Picolínicos/química , Cristalografía por Rayos X , Enlace de Hidrógeno , Estructura Molecular
9.
Acta Crystallogr C ; 65(Pt 2): o42-5, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19190385

RESUMEN

In the crystal structures of 2-amino-4,6-dimethoxypyrimidinium 2,4,6-trinitrophenolate (picrate), C(6)H(10)N(3)O(2)(+).C(6)H(2)N(3)O(7)(-), (I), and 2,4-diamino-5-(4-chlorophenyl)-6-ethylpyrimidin-1-ium (pyrimethaminium or PMN) picrate dimethyl sulfoxide solvate, C(12)H(14)ClN(4)(+).C(6)H(2)N(3)O(7)(-).C(2)H(6)OS, (II), the 2-amino-4,6-dimethoxypyrimidine and PMN cations are protonated at one of the pyrimidine N atoms. The picrate anion interacts with the protonated cations through bifurcated N-H...O hydrogen bonds, forming R(2)(1)(6) and R(1)(2)(6) ring motifs. In (I), Z' = 2. In (II), two inversion-related PMN cations are connected through a pair of N-H...N hydrogen bonds involving the 4-amino group and the uncharged N atom of the pyrimidine ring, forming a cyclic hydrogen-bonded R(2)(2)(8) motif. In addition to the pairing, the O atom of the dimethyl sulfoxide solvent molecule bridges the 2-amino and 4-amino groups on both sides of the paired bases, resulting in a self-complementary ...DADA... array of quadruple hydrogen-bonding patterns.


Asunto(s)
Dimetilsulfóxido/química , Picratos/química , Pirimetamina/química , Pirimidinas/química , Cristalografía , Enlace de Hidrógeno , Modelos Moleculares
10.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): o2122, 2009 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-21577536

RESUMEN

The title compound, C(26)H(24)N(2)O(4), consists of a symmetrical mol-ecule that lies across a crystallographic inversion centre. The C-C distance in the triple bond is 1.188 (2) Šand there is also an inter-molecular C-H⋯O contact from a terminal acetyl-ene C-H to one of the dimiide O atoms [3.4349 (19) Å].

11.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): o2184, 2009 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-21577588

RESUMEN

The title compound, C(30)H(30)N(2)O(6), has crystallographic inversion symmetry with the nitro-gen atom and the two oxygen atoms of the naphthalene diimide system deviating by -0.243 (2), 0.109 (3) and 0.247 (2) Å, respectively, from the plane defined by the carbon atoms.

12.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): o2484, 2009 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-21577935

RESUMEN

The planar [maximum deviation 0.0066 (4) Å] symmetrical mol-ecule of the title compound, C(10)H(6)S(2), lies across a crystallographic inversion centre. The thio-phene rings are rotationally disordered about the acetyl-ene bond, with the two pseudo inversion-related S atoms in 0.80:0.20 occupancy sites. The C C bond distance is 1.195 (9) Å.

13.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): o426, 2008 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-21201453

RESUMEN

In the title compound, C(6)H(10)N(3) (+)·C(7)H(3)N(2)O(6) (-)·2H(2)O, the amino-pyrimidine mol-ecule is protonated at one of the pyrimidine N atoms. The carboxyl-ate group of the 3,5-dinitro-benzoate anion inter-acts with the protonated pyrimidine N atom and the 2-amino group through a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) motif. Two inversion-related pyrimidine rings are linked via a pair of N-H⋯N hydrogen bonds, also forming an R(2) (2)(8) ring motif.

14.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o107-8, 2007 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-21200672

RESUMEN

In the title cocrystal, C(6)H(9)N(3)O(2)·C(7)H(7)NO(2), the asymmetric unit contains two crystallographically independent 2-amino-4,6-dimeth-oxy pyrimidine-anthranilic acid adducts. The 2-amino-4,6-dimeth-oxy pyrimidine mol-ecules inter-act with the carboxylic group of the respective anthranilic acid mol-ecules through N-H⋯O and O-H⋯N hydrogen bonds, forming a cyclic hydrogen-bonded motif R(2) (2)(8). The pyrimidine mol-ecules also form base pairs via a pair of N-H⋯N hydrogen bonds, forming another R(2) (2)(8) motif. The typical intra-molecular N-H⋯O hydrogen bond is observed in the anthranilic acid mol-ecules. Furthermore, the crystal structure is stabilized by C-H⋯O hydrogen bonds.

15.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 3): 382-6, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-27006813

RESUMEN

The anhydrous salts of the Lewis base 1,8-di-aza-bicyclo-[5.4.0]undec-7-ene (DBU) with 4-amino-benzoic acid [1-aza-8-azoniabi-cyclo-[5.4.0]undec-7-ene 4-amino-benzoate, C9H17N2 (+)·C7H6NO2 (-) (I)], 3,5-di-nitro-benzoic acid [1-aza-8-azoniabi-cyclo-[5.4.0]undec-7-ene 3,5-di-nitro-benzoate, C9H17N2 (+)·C7H3N2O6 (-), (II)] and 3,5-di-nitro-salicylic acid (DNSA) [1-aza-8-azoniabi-cyclo-[5.4.0]undec-7-ene 2-hy-droxy-3,5-di-nitro-benzoate, C9H17N2 (+)·C7H3N2O7 (-), (III)] have been determined and their hydrogen-bonded structures are described. In both (II) and (III), the DBU cations have a common disorder in three of the C atoms of the six-membered ring moieties [site-occupancy factors (SOF) = 0.735 (3)/0.265 (3) and 0.686 (4)/0.314 (4), respectively], while in (III), there is additional rotational disorder in the DNSA anion, giving two sites (SOF = 0.72/0.28, values fixed) for the phenol group. In the crystals of (I) and (III), the cation-anion pairs are linked through a primary N-H⋯Ocarbox-yl hydrogen bond [2.665 (2) and 2.869 (3) Å, respectively]. In (II), the ion pairs are linked through an asymmetric three-centre R 1 (2)(4), N-H⋯O,O' chelate association. In (I), structure extension is through amine N-H⋯Ocarbox-yl hydrogen bonds between the PABA anions, giving a three-dimensional structure. The crystal structures of (II) and (III) are very similar, the cation-anion pairs being associated only through weak C-H⋯O hydrogen bonds, giving in both overall two-dimensional layered structures lying parallel to (001). No π-π ring associations are present in any of the structures.

16.
Acta Crystallogr C Struct Chem ; 72(Pt 2): 105-11, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26846493

RESUMEN

The morpholinium (tetrahydro-2H-1,4-oxazin-4-ium) cation has been used as a counter-ion in both inorganic and organic salt formation and particularly in metal complex stabilization. To examine the influence of interactive substituent groups in the aromatic rings of benzoic acids upon secondary structure generation, the anhydrous salts of morpholine with salicylic acid, C4H10NO(+)·C7H5O3(-), (I), 3,5-dinitrosalicylic acid, C4H10NO(+)·C7H3N2O7(-), (II), 3,5-dinitrobenzoic acid, C4H10NO(+)·C7H3N2O6(-), (III), and 4-nitroanthranilic acid, C4H10NO(+)·C7H5N2O4(-), (IV), have been prepared and their hydrogen-bonded crystal structures are described. In the crystal structures of (I), (III) and (IV), the cations and anions are linked by moderately strong N-H...Ocarboxyl hydrogen bonds, but the secondary structure propagation differs among the three, viz. one-dimensional chains extending along [010] in (I), a discrete cyclic heterotetramer in (III), and in (IV), a heterotetramer with amine N-H...O hydrogen-bond extensions along b, giving a two-layered ribbon structure. With the heterotetramers in both (III) and (IV), the ion pairs are linked though inversion-related N-H...Ocarboxylate hydrogen bonds, giving cyclic R4(4)(12) motifs. With (II), in which the anion is a phenolate rather than a carboxylate, the stronger assocation is through a symmetric lateral three-centre cyclic R1(2)(6) N-H...(O,O') hydrogen-bonding linkage involving the phenolate and nitro O-atom acceptors of the anion, with extension through a weaker O-H...Ocarboxyl hydrogen bond. This results in a one-dimensional chain structure extending along [100]. In the structures of two of the salts [i.e. (II) and (IV)], there are also π-π ring interactions, with ring-centroid separations of 3.5516 (9) and 3.7700 (9) Šin (II), and 3.7340 (9) Šin (IV).

17.
Acta Crystallogr C Struct Chem ; 72(Pt 10): 738-742, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27703120

RESUMEN

The study of ternary systems is interesting because it introduces the concept of molecular preference/competition into the system where one molecule may be displaced because the association between the other two is significantly stronger. Current definitions of a tertiary system indicate that solvent molecules are excluded from the molecule count of the system and some of the latest definitions state that any molecule that is not a solid in the parent form at room temperature should also be excluded from the molecule count. In the structure of the quinoline adduct hydrate of tryptaminium 3,5-dinitrobenzoate, 3C10H13N2+·3C7H3N2O6-·2C9H7N·2H2O, the asymmetric unit comprises multiple cation and anion species which are conformationally similar among each type set. In the crystal, a one-dimensional hydrogen-bonded supramolecular structure is generated through extensive intra- and inter-unit aminium N-H...O and N-H...N, and water O-H...O hydrogen bonds. Within the central-core hydrogen-bonding associations, conjoined cyclic R44(10), R53(10) and R44(12) motifs are generated. The unit is expanded into a one-dimensional column-like polymer extending along [010]. Present also in the crystal packing of the structure are a total of 19 π-π interactions involving both cation, anion and quinoline species [ring-centroid separation range = 3.395 (3)-3.797 (3) Å], as well as a number of weak C-H...O hydrogen-bonding associations. The presence of the two water molecules in the crystal structure is considered to be the principal causative factor in the low symmetry of the asymmetric unit.

18.
Thromb Haemost ; 116(2): 337-48, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27121899

RESUMEN

Pharmacogenomics (PGx) guided warfarin dosing, using a comprehensive dosing algorithm, is expected to improve dose optimisation and lower the risk of adverse drug reactions. As a complementary tool, a simple genotype-dosing table, such as in the US Food and Drug Administration (FDA) Coumadin drug label, may be utilised for general risk assessment of likely over- or under-anticoagulation on a standard dose of warfarin. This tool may be used as part of the clinical decision support for the interpretation of genetic data, serving as a first step in the anticoagulation therapy decision making process. Here we used a publicly available warfarin dosing calculator (www.warfarindosing.org) to create an expanded gene-based warfarin dosing table, the CPMC-WD table that includes nine genetic variants in CYP2C9, VKORC1, and CYP4F2. Using two datasets, a European American cohort (EUA, n=73) and the Quebec Warfarin Cohort (QWC, n=769), we show that the CPMC-WD table more accurately predicts therapeutic dose than the FDA table (51 % vs 33 %, respectively, in the EUA, McNemar's two-sided p=0.02; 52 % vs 37 % in the QWC, p<1×10(-6)). It also outperforms both the standard of care 5 mg/day dosing (51 % vs 34 % in the EUA, p=0.04; 52 % vs 31 % in the QWC, p<1×10(-6)) as well as a clinical-only algorithm (51 % vs 38 % in the EUA, trend p=0.11; 52 % vs 45 % in the QWC, p=0.003). This table offers a valuable update to the PGx dosing guideline in the drug label.


Asunto(s)
Anticoagulantes/administración & dosificación , Anticoagulantes/farmacocinética , Farmacogenética/estadística & datos numéricos , Warfarina/administración & dosificación , Warfarina/farmacocinética , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Anticoagulantes/efectos adversos , Fibrilación Atrial/sangre , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/genética , Estudios de Cohortes , Citocromo P-450 CYP2C9/genética , Familia 4 del Citocromo P450/genética , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variantes Farmacogenómicas , Valor Predictivo de las Pruebas , Vitamina K Epóxido Reductasas/genética , Warfarina/efectos adversos , Adulto Joven
19.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 11): 1392-6, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26594518

RESUMEN

The anhydrous salts morpholinium (tetra-hydro-2-H-1,4-oxazin-4-ium) phen-oxy-acetate, C4H10NO(+)·C8H7O3 (-), (I), morpholinium (4-fluoro-phen-oxy)acetate, C4H10NO(+)·C8H6 FO3 (-), (II), and isomeric morpholinium (3,5-di-chloro-phen-oxy)acetate (3,5-D), (III), and morpholinium (2,4-di-chloro-phen-oxy)acetic acid (2,4-D), C4H10NO(+)·C8H5Cl2O3 (-), (IV), have been determined and their hydrogen-bonded structures are described. In the crystals of (I), (III) and (IV), one of the the aminium H atoms is involved in a three-centre asymmetric cation-anion N-H⋯O,O' R 1 (2)(4) hydrogen-bonding inter-action with the two carboxyl O-atom acceptors of the anion. With the structure of (II), the primary N-H⋯O inter-action is linear. In the structures of (I), (II) and (III), the second N-H⋯Ocarbox-yl hydrogen bond generates one-dimensional chain structures extending in all cases along [100]. With (IV), the ion pairs are linked though inversion-related N-H⋯O hydrogen bonds [graph set R 4 (2)(8)], giving a cyclic hetero-tetra-meric structure.

20.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 12): 1457-61, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26870404

RESUMEN

The crystal structures of two erbium(III) complexes with 4-amino-benzoic acid (4-ABAH), namely bis-(µ2-4-amino-benzoato-κ(2) O:O')bis-[bis(4-amino-benzoato-κ(2) O,O')di-aqua-erbium(III)] dihydrate, [Er2(C7H6NO2)6(H2O)4]·2H2O, (I), and 4-chloro-3-nitro-benzoic acid (CLNBAH), namely poly[hexa-kis-(µ2-4-chloro-3-nitro-benzoato-κ(2) O:O')bis-(dimethyl sulfoxide-κO)dierbium(III)], [Er2(C7H3ClNO4)6(C2H6OS)2] n , (II), have been determined. In the structure of solvatomorphic compound (I), the symmetry-related irregular ErO8 coordination polyhedra in the discrete centrosymmetric dinuclear complex comprise two monodentate water mol-ecules and six carboxyl-ate O-atom donors, four from two bidentate carboxyl-ate O,O'-chelate groups and two from the bis-monodentate O:O'-bridging group of the third 4-ABA anion. The Er-O bond-length range is 2.232 (3)-2.478 (3) Šand the Er⋯Er separation in the dinuclear complex unit is 4.7527 (4) Å. One of the coordinating water mol-ecules is involved in an intra-unit O-H⋯O hydrogen-bonding association with an inversion-related carboxyl-ate O-atom acceptor. In contrast, the anhydrous compound (II) is polymeric, based on centrosymmetric dinuclear repeat units comprising ErO7 coordination polyhedra which involve four O-atom donors from two bidentate O:O'-bridging carboxyl-ate groups, one O-atom donor from the monodentate dimethyl sulfoxide ligand and two O-atom donors from the third bridging CLNBA anion. The latter provides the inter-unit link in the one-dimensional coordination polymer extending along [100]. The Er-O bond-length range in (II) is 2.239 (6)-2.348 (6) Šand the Er⋯Er separation within the dinuclear unit is 4.4620 (6) Å. In the crystal of (I), extensive inter-dimer O-H⋯O and N-H⋯O hydrogen-bonding inter-actions involving both the coordinating water mol-ecules and the solvent water mol-ecules, as well as the amine groups of the 4-ABA anions, give an overall three-dimensional network structure. Within this structure are also weak π-π ring inter-actions between two of the coordinating ligands [ring-centroid separations = 3.676 (3) and 3.711 (2) Å]. With (II), only weak intra-polymer C-H⋯O, C-H⋯Cl and C-H⋯S inter-actions are present.

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