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1.
Acta Crystallogr C Struct Chem ; 72(Pt 10): 738-742, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27703120

RESUMO

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.

2.
Thromb Haemost ; 116(2): 337-48, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27121899

RESUMO

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.


Assuntos
Anticoagulantes/administração & dosagem , Anticoagulantes/farmacocinética , Farmacogenética/estatística & dados numéricos , Varfarina/administração & dosagem , Varfarina/farmacocinética , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Anticoagulantes/efeitos adversos , Fibrilação Atrial/sangue , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/genética , Estudos de Coortes , Citocromo P-450 CYP2C9/genética , Família 4 do Citocromo P450/genética , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variantes Farmacogenômicos , Valor Preditivo dos Testes , Vitamina K Epóxido Redutases/genética , Varfarina/efeitos adversos , Adulto Jovem
3.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 3): 382-6, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27006813

RESUMO

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.

4.
Acta Crystallogr C Struct Chem ; 72(Pt 2): 105-11, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26846493

RESUMO

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).

5.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 11): 1392-6, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26594518

RESUMO

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.

6.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 6): 671-4, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26090147

RESUMO

The anhydrous salts of 2-(1H-indol-3-yl)ethanamine (tryptamine) with isomeric (2,4-di-chloro-phen-oxy)acetic acid (2,4-D) and (3,5-di-chloro-phen-oxy)acetic (3,5-D), both C10H13N2 (+)·C8H5Cl2O3 (-) [(I) and (II), respectively], have been determined and their one-dimensional hydrogen-bonded polymeric structures are described. In the crystal of (I), the aminium H atoms are involved in three separate inter-species N-H⋯O hydrogen-bonding inter-actions, two with carboxyl-ate O-atom acceptors and the third in an asymmetric three-centre bidentate carboxyl-ate O,O' chelate [graph set R 1 (2)(4)]. The indole H atom forms an N-H⋯Ocarboxyl-ate hydrogen bond, extending the chain structure along the b-axis direction. In (II), two of the three aminium H atoms are also involved in N-H⋯Ocarboxyl-ate hydrogen bonds similar to (I) but with the third, a three-centre asymmetric inter-action with carboxyl-ate and phen-oxy O atoms is found [graph set R 1 (2)(5)]. The chain polymeric extension is also along b. There are no π-π ring inter-actions in either of the structures. The aminium side-chain conformations differ significantly between the two structures, reflecting the conformational ambivalence of the tryptaminium cation, as found also in the benzoate salts.

7.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 12): 1457-61, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26870404

RESUMO

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.

8.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 10): 183-7, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25484647

RESUMO

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)].

9.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 11): 294-7, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25484726

RESUMO

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].

10.
Acta Crystallogr C Struct Chem ; 70(Pt 6): 606-12, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24898967

RESUMO

The two-dimensional polymeric structures of the caesium complexes with the phenoxyacetic acid analogues (4-fluorophenoxy)acetic acid, (3-chloro-2-methylphenoxy)acetic acid and the herbicidally active (2,4-dichlorophenoxy)acetic acid (2,4-D), namely poly[[µ5-(4-fluorophenoxy)acetato][µ4-(4-fluorophenoxy)acetato]dicaesium], [Cs2(C8H6FO3)2]n, (I), poly[aqua[µ5-(3-chloro-2-methylphenoxy)acetato]caesium], [Cs(C9H8ClO3)(H2O)]n, (II), and poly[[µ7-(2,4-dichlorophenoxy)acetato][(2,4-dichlorphenoxy)acetic acid]caesium], [Cs(C8H5Cl2O3)(C8H6Cl2O3)]n, (III), are described. In (I), the Cs(+) cations of the two individual irregular coordination polyhedra in the asymmetric unit (one CsO7 and the other CsO8) are linked by bridging carboxylate O-atom donors from the two ligand molecules, both of which are involved in bidentate chelate Ocarboxy,Ophenoxy interactions, while only one has a bidentate carboxylate O,O'-chelate interaction. Polymeric extension is achieved through a number of carboxylate O-atom bridges, with a minimum Cs···Cs separation of 4.3231 (9) Å, giving layers which lie parallel to (001). In hydrated complex (II), the irregular nine-coordination about the Cs(+) cation comprises a single monodentate water molecule, a bidentate Ocarboxy,Ophenoxy chelate interaction and six bridging carboxylate O-atom bonding interactions, giving a Cs···Cs separation of 4.2473 (3) Å. The water molecule forms intralayer hydrogen bonds within the two-dimensional layers, which lie parallel to (100). In complex (III), the irregular centrosymmetric CsO6Cl2 coordination environment comprises two O-atom donors and two ring-substituted Cl-atom donors from two hydrogen bis[(2,4-dichlorophenoxy)acetate] ligand species in a bidentate chelate mode, and four O-atom donors from bridging carboxyl groups. The duplex ligand species lie across crystallographic inversion centres, linked through a short O-H···O hydrogen bond involving the single acid H atom. Structure extension gives layers which lie parallel to (001). The present set of structures of Cs salts of phenoxyacetic acids show previously demonstrated trends among the alkali metal salts of simple benzoic acids with no stereochemically favourable interactive substituent groups for formation of two-dimensional coordination polymers.

11.
Genome Med ; 5(10): 93, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24134832

RESUMO

Implementation of pharmacogenomics (PGx) in clinical care can lead to improved drug efficacy and reduced adverse drug reactions. However, there has been a lag in adoption of PGx tests in clinical practice. This is due in part to a paucity of rigorous systems for translating published clinical and scientific data into standardized diagnostic tests with clear therapeutic recommendations. Here we describe the Pharmacogenomics Appraisal, Evidence Scoring and Interpretation System (PhAESIS), developed as part of the Coriell Personalized Medicine Collaborative research study, and its application to seven commonly prescribed drugs.

12.
Acta Crystallogr C ; 69(Pt 9): 1034-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24005516

RESUMO

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.


Assuntos
Ácidos Naftalenoacéticos/química , Nitrobenzoatos/química , Sais/química , Tiadiazóis/química , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular
13.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 5): o786-7, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23723930

RESUMO

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.

14.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): o835-6, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23795025

RESUMO

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.

15.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): o884, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23795060

RESUMO

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.

16.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): o941-2, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23795105

RESUMO

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].

17.
Dalton Trans ; 40(23): 6278-88, 2011 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-21409200

RESUMO

Understanding how the size, charge and number of available pores in porous material influences the uptake and release properties is important for optimising their design and ultimately their application. Unfortunately there are no standard methods for screening porous materials in solution and therefore formulations must be developed for each encapsulated agent. This study investigates the potential of a library of radiotracers (nuclear sensors) for assessing the binding properties of hollow silica shell materials. Uptake and release of Cu(2+) and Co(2+) and their respective complexes with polyazacarboxylate macrocycles (dota and teta) and a series of hexa aza cages (diamsar, sarar and bis-(p-aminobenzyl)-diamsar) from the hollow silica shells was monitored using their radioisotopic analogues. Coordination chemistry of the metal (M) species, subtle alterations in the molecular architecture of ligands (Ligand) and their resultant complexes (M-Ligand) were found to significantly influence their uptake over pH 3 to 9 at room temperature. Positively charged species were selectively and rapidly (within 10 min) absorbed at pH 7 to 9. Negatively charged species were preferentially absorbed at low pH (3 to 5). Rates of release varied for each nuclear sensor, and time to establish equilibrium varied from minutes to days. The subtle changes in design of the nuclear sensors proved to be a valuable tool for determining the binding properties of porous materials. The data support the development of a library of nuclear sensors for screening porous materials for use in optimising the design of porous materials and the potential of nuclear sensors for high through-put screening of materials.


Assuntos
Portadores de Fármacos/química , Compostos Aza/química , Cobalto/química , Radioisótopos de Cobalto/química , Complexos de Coordenação/química , Cobre/química , Radioisótopos de Cobre/química , Concentração de Íons de Hidrogênio , Porosidade , Dióxido de Silício/química , Relação Estrutura-Atividade , Temperatura
18.
Acta Crystallogr C ; 66(Pt 7): o324-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20603557

RESUMO

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.


Assuntos
Maleatos/química , Ácidos Ftálicos/química , Ácidos Picolínicos/química , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular
19.
Acta Crystallogr C ; 65(Pt 2): o42-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19190385

RESUMO

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.


Assuntos
Dimetil Sulfóxido/química , Picratos/química , Pirimetamina/química , Pirimidinas/química , Cristalografia , Ligação de Hidrogênio , Modelos Moleculares
20.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): o2122, 2009 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-21577536

RESUMO

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].

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