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Isonicotinic acid anthracen-9-ylmethylene-hydrazide (AI), prepared from anthracene-9-carboxaldehyde and isoniazid, exhibited mechano-responsive luminescent emissions; for instance, gentle pressing of the weakly emissive crystals of AI (λem 527 nm) produced a yellow-green emissive material (λem 540 nm). Also, the mechano-luminescent emissions of AI could be easily switched “off” upon exposure to N,N-dimethylformamide. Contrastingly, under the same conditions, benzoic acid anthracen-9-ylmethylene-hydrazide (AB) did not exhibit mechano-responsive luminescent emissions. On the basis of UV–vis, fluorescence, Fourier transform infrared spectroscopy, and powder X-ray diffraction (XRD) studies, we suggest that mechano-luminescent emissions of AI were triggered by mechanically induced deformations in the lattice, which affected the intermolecular interactions and aromatic stacking behavior. Again, the mechano-luminescent emissions of AI were switched off when mixed with oxalic acid, although accompanied by a conco...

Three types of lanthanide coordination polymers based on mixed methylmalonic acid (H2MMA) and isonicotinic acid (HINA), two-dimensional (2D) [Ln2(MMA)2(INA)2(H2O)3]n (Ln = Eu (1); Gd (2)) and [Ln(MMA)(INA)(H2O)2]n (Ln = Gd (3); Tb (4)) as well as one-dimensional (1D) [Dy(MMA)(INA)(H2O)2]n (5), have been hydrothermally synthesized, which can be controlled by the usage amount of H2MMA or the type of Ln3+ ion. Complexes 1 and 2 contain two kinds of 1D lanthanide chain units (wave and linear), which are alternately linked by the MMA2– and INA– ligands to form a 2D layer structure. Complexes 3 and 4 also have a 2D layer structure, consisting of 1D linear lanthanide chain units, MMA2– and INA– linkers. Compound 5 shows a 1D linear chain structure, in which the neighboring Dy3+ ions are fastened by the carboxylate groups from MMA2– and INA– ligands. The magnetic studies reveal the presence of ferromagnetic Gd···Gd coupling in the 1D chain units of 2 and 3, which display significant cryogenic magnetocaloric effec...

Formation of multicomponent crystals (MCCs) of L-tryptophan (TRP) with N-heterocyclic carboxylic acids such as 2-picolinic acid (PA) and its 3- or 4-substituent isomers (nicotinic acid or isonicotinic acid), pyrazinecarboxylic acid (PZCA), 2,3-pyrazinedicarboxylic acid (2,3-PZDCA), 2-quinaldic acid (QA), and its 3-subsituent isomer (3-QA) is investigated in this manuscript. The investigation results in four multicomponent solid forms of the amino acid with coformers where the electron withdrawing functional group (−COOH) is present in the ortho-substituent to N-heterocyclic rings. The isomers of PA or QA having −COOH at the meta- or para- position failed to produce new phases. These solid phases were identified by powder X-ray diffraction results, and the MCCs derived from 2-picolinic acid (1) and 2,3-pyrazinedicarboxylic acids (3) were further characterized with single crystal X-ray diffraction. The crystal structure of TRP-PA (1) reveal a rare form of cocrystal where both the amino acid and the picolini...

Hydrochlorothiazide (HCT) is a diuretic drug with poor solubility and permeability. Physicochemical properties of HCT have been modified by cocrystallization with piperazine (PPZ), tetramethylpyrazine (TMPZ), picolinamide (PCM), isoniazid (INZ), malonamide (MAM), and isonicotinic acid (INIC) using mechanochemical grinding (liquid assisted and neat). The solids obtained were characterized by single crystal X-ray diffraction (SCXRD), powder X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry and subjected to solubility and membrane permeability studies. SCXRD showed that the N-H...O sulfonamide catemer synthons found in the stable polymorph of pure HCT have been replaced by drug-coformer heterosynthons in the cocrystals. HCT-PPZ and HCT-PCM cocrystals showed improvement in solubility and membrane permeability/diffusion compared to the parent active pharmaceutical ingredient. The improved solubility and diffusion rates are due to the drug-coformer interactions in the new solid forms. A structure-property relationship is examined to evaluate the solubility and diffusion rates of the new solid forms. The cocrystal with INIC, which could not be prepared previously by conventional methods, was obtained by prolonged grinding for 6 days.

Actinide-based metal–organic materials have drawn much attention due to their intriguing 5f bonding properties and promising applications in nuclear fuels and other fields. Introduction of weak interactions, such as halogen bonds, into actinide–organic hybrid materials will provide them with more flexibility and dynamics. The first case of halogen bonded three-dimensional (3D) uranyl–organic supramolecular frameworks with regular nanoscale channels has been obtained from multifunctional halogen-substituted isonicotinic acids. Distinct from conventional halogen bonded uranyl–organic frameworks, the supramolecular networks obtained here consist of three-component cocrystals and have been assemblied by intensive supramolecular networks to obtain an extended 3D geometry. Moreover, secondary “X3” and “X6” halogen–halogen interactions resulting from the driving forces of primary hydrogen bonds have been found and analyzed by quantum chemical calculation, indicating their feature of weak bonding and special geom...

The synthesis and characterization of {[Co9(INA)18(H2O)6]·11DMF·15H2O}∞ (Co9-INA·11DMF·15H2O) (INA- = the anion of isonicotinic acid) is reported. It exhibits a rigid 3D-porous structure with a Co9 repeating unit consisting of four [CoII2(μ-O2CR)2(μ-H2O)] subunits (two unique) linked through bridging INA- ligands to an isolated CoII ion (half unique). The [CoII2] dimers and the isolated CoII ion have assembled to create a trinodal (6,7,8)-coordinated network with point symbol (32.411.56.62)2(32.418.54.64)2(34.44.54.63). Gas sorption studies revealed that Co9-INA exhibits 910 m2 g-1 BET area, 4.2 mmol g-1 CO2 uptake at 273 K/1 bar, and 6.7 CO2/CH4 selectivity at zero coverage. Furthermore, Co9-INA displays capability for exchange of the guest solvent molecules by various organic molecules in a single-crystal to single-crystal fashion. Direct and alternating current magnetic susceptibility studies revealed the existence of dominant antiferromagnetic interactions between the Co2+ ions that result in a paramagnetic ST = 3/2 spin ground state value. Overall, this work emphasizes the potential of relatively simple and inexpensive polytopic ligands, such as isonicotic acid, to stabilize microporous MOFs with significant CO2 sorption capacity. © 2014 American Chemical Society. 15 1 185 193 Cited By :11

A family of polyoxometalate compounds based on 1:13 polyoxoanions [MnV13O38]7–, organic molecules, and lanthanide cations, H[{La2(DMF)5(H2O)4}{MnV13O38}]·DMF·5H2O (1), H[{Ce2(DMF)2(H2O)7}{MnV13O38}]·0.5DMF·5.5H2O (2), H2[{K(H2O)2}2{Nd(DMF)(H2O)3}{MnV13O38}]·5H2O (3), H[{Ln2(C6H5NO2)3(H2O)6}{[MnV13O38}]·C6H5NO2·10H2O (Ln = La 4, Ce 5), and H2.5[{Pr(C6H5NO2)(H2O)3.5}{Pr0.5(H2O)2}{MnV13O38}]·0.5C6H5NO2·10H2O (6) (DMF = N,N-dimethylformamide; C6H5NO2 = isonicotinic acid), have been obtained utilizing a conventional method of aqueous solution and further characterized by elemental analysis, IR spectrum, UV spectrum, thermogravimetric analysis, and single-crystal X-ray diffraction. Compounds 1 and 2 exhibit a one-dimensional extended chain structure constructed by [MnV13O38]7– and lanthanide-organic coordination linkage, while compound 3 reveals three-dimensional (3D) open framework formed by polyoxoanion-lanthanide chains and potassium cations. Compounds 4–6 exhibit 3D supramolecular framework architectures ba...

The isonicotinoylhydrazones and their coordination compounds have antibacterial, antifungal, antitubercular, antitumor, and anticonvulsant activities. A typical method employed in the preparation of isonicotinoylhydrazones involves the usage of the volatile organic solvents during the condensation reaction between isonicotinic acid hydrazide and carbonyl compounds. It has been shown that the solvent-free technique can be applied to obtain crystalline compounds. Reaction of isoniazid with carbonyl compound under solvent-free conditions results in microcrystalline solid state isonicotinoylhydrazones. The influence of solvent effect on the mechanism of condensation reaction was evaluated and the most significant intermediates and transition states, in the gas phase and in the presence of water and methanol were resolved. The solvent has positive effect on the reaction mechanism, but the organic solvent is unnecessary during the synthesis of crystalline isonicotinoylhydrazones derived from aldehydes. Mixing s...

Clofazimine (CFZ), an antibacterial and anti-inflammatory drug, is also recommended by the World Health Organization for the treatment of leprosy in combination with dapsone and rifampicin. It is an iminophenazine derivative and classified as a Biopharmaceutics Classification System (BCS) class II drug because of poor aqueous solubility (10 mg L–1). Despite it being a very classical drug known for more than five decades, there is no systematic study of CFZ salts for solubility and stability enhancement. We report a solid form screen of CFZ with pharmaceutically acceptable coformers/acids. Salts of CFZ with methanesulfonic acid, maleic acid, isonicotinic acid, nicotinic acid, malonic acid, and salicylic acid in an equimolar ratio as well as an amorphous phase of CFZ are reported. All new solid phases were characterized by FT-IR, powder X-ray diffraction, and differential scanning calorimetry, and confirmed by single crystal X-ray diffraction. The acid proton is transferred to the imine nitrogen of CFZ in a...

Seven complexes based on the ligands 4,6-bis(4-pyridyl)-1,3,5-triazin-2-ol (4-HOBPT) and 4,6-bis(3-pyridyl)-1,3,5-triazin-2-ol (3-HOBPT), namely, [Fe(4-OBPT)2(H2O)2]·6H2O (2), M(4-OBPT)(INA)(H2O) (M = Co(II) (3a), Fe(II) (3b), Zn(II) (3c), HINA = isonicotinic acid), [Co(3-OBPT)2(H2O)2]·H2O (4), and [M(3-OBPT)(NA)(H2O)]·0.5CH3OH (M = Co(II) (5a), Ni(II) (5b), HNA = nicotinic acid), have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction. The thermal stability and coordination model of the ligands are extremely dependent on the reaction temperature and the presence of metal ions. In the range of 90−120 °C, unique complexes 2 and 4 were obtained and the ligands are a N,O-bimonodentate coordination model. At 130 °C, complexes 3 and 5 were afforded in yields of 12−48% depending on the metal ions, in which both of the ligands act as a N,N,O-trimonodentate triangular ligand and the INA and NA anions are generated in situ by hydrolysis of the corresponding parents...

A new flexible bowl-shaped zwitterionic complex, 1,1′,1′′-(2,4,6-trimethylbenzene-1,3,5-triyl)tris(methylene)tris(4-carboxypyridinium) tribromide (H3LBr3) was designed and synthesized, which was subsequently used as an efficient ligand to construct four interesting coordination polymers of [Cu2Cl2L2(H2O)2]·Cl·Br·4H2O (1), [ZnLBr]·NO3·H2O (2), [Cd2L2Br2]·2NO3·4H2O (3), and [Cd2L2(Inic)(H2O)4(MeOH)2]·Br·2NO3·3H2O (Inic = isonicotinlate, 4) by reaction of L ligand with corresponding metal salts or in the presence of isonicotinic acid. In these coordination polymers, L ligands link up metal nodes to form distinct linear networks. Two bowl mouths of two L ligands surround each other to form a ball-shaped building synthon in compounds 1 and 4, while the linear networks in 2 and 3 are in cylinder-shaped configurations. The luminescent spectra of L and compounds 1, 2, 3, and 4 suggested that the potential field around L ligand should be an important factor on the fluorescent emissions. The successful construction...

Hydrothermal reactions of 2-phosphonic isonicotinic acid (pinH3, HOOC-C5H3N-PO3H2) with cupric chloride afford two copper phosphonates: Cu3(pin)2(H2O)2 (1) and Cu(pinH2)2 (2). Compound 1 crystallizes in the monoclinic space group C2/c with a = 15.913(5) A, b = 6.016(2) A, c = 18.043(5) A, β = 90.518(9)°, and V = 1727.2(8) A3. In this structure, dimers of {Cu2O2} are linked by {CuO6} octahedra through O(1W) forming an inorganic chain. The adjacent chains are further connected by {CPO3} tetrahedra to form an undulating inorganic layer. The inorganic layers are pillared by the pyridyl groups of the ligand, resulting in a three-dimensional framework structure. Compound 2 crystallizes in the monoclinic space group C2/c with a = 19.039(3) A, b = 7.185(1) A, c = 12.355(2) A, β = 116.666(3)°, and V = 1510.4(4) A3. It shows a chain structure in which the adjacent {CuN2O4} octahedra are doubly bridged by two phosphonate ligands. Ferromagnetic interactions are found to be mediated between the Cu(II) centers in 1. Ac...

By using linear multifunctional ligands with different geometries, three novel three-dimensional (3D) Ln−M heterometallic coordination polymers, [Nd(H2O)2(CuI)2(nic)3]·H2O (1) (Hnic = nicotinic acid) and [LnCu(inic)2(ox)]·H2O [Ln = Nd (2), Eu (3); Hinic = isonicotinic acid, H2ox = oxalic acid], have been synthesized under hydrothermal conditions. Compound 1 exhibits a novel 3D coordination framework constructed by Cu4I4 clusters, Nd centers, and nic ligands. Our present work represents the first example of 3D Ln−M heterometallic coordination framework incorporating discrete cubane transition metal clusters covalently bonded to lanthanide centers through linear ligands. An unusual chemical rearrangement from Hinic to ox occurs in the formation of 2 and 3. Compounds 2 and 3 are isostructural and possess the first 3D coordination framework based on the linkage of two-dimensional layers constructed by tetranuclear Ln2Cu2 clusters and inic ligands. Furthermore, the luminescent properties of 3 were studied.

Three novel porous coordination polymers based on lead(II) and isonicotinic acid N-oxide, [Pb(INO)2]2·7H2O (1), [Pb(INO)2]·nH2O (2), and [Pb4(OH)4(INO)4]·nH2O (3) (HINO = isonicotinic acid N-oxide), have been synthesized and characterized through single-crystal X-ray diffraction. Compound 1 features a most remarkable and unique three-dimensional (3D) framework with two distinct kinds of channels showing different sizes and shapes, which are occupied by two kinds of water clusters, according to the size and shape of the channels. Compound 2 possesses a 3D framework built up from one-dimensional (1D) Pb−O chains and INO ligands with 1D rectangular channels, in which lattice water molecules are located. The structure of 3 consists of [Pb4(OH)4]4+ cluster inorganic building blocks, which connect with μ4-INO ligands through oxygen atoms from N-oxide moieties and carboxylate groups of INO to form 8.7 × 8.7 A2 rhombic channels running along the c-axis. In addition, the photoluminescence properties of coordinatio...

By control of mixed ligands with particular coordination sites, three novel three-dimensional (3D) 4d−4f heterometallic coordination polymers, [Ln4(H2O)2Ag(1,3-bdc)4(inic)5]·nH2O (Ln = Nd (1), n = 0.25; Eu (2), n = 0; 1,3-H2bdc = 1,3-benzenedicarboxylic acid and Hinic = isonicotinic acid) and [Nd(H2O)Ag(1,2-bdc)(inic)2] (3) (1,2-H2bdc = 1,2-benzenedicarboxylic acid), have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR, thermogravimetric (TG) analysis, and single-crystal X-ray diffraction. Compounds 1−3 crystallize in the monoclinic system, space group C2/c. Compounds 1 and 2 are isostructural and exhibit novel 3D coordination frameworks constructed from two-dimensional (2D) wavelike lanthanide carboxylate layers and Ag(inic)4 complexes. To the best of our knowledge, they represent the first examples of 3D 4d−4f heterometallic coordination frameworks, in which the transition metal complexes bond to a 3D lanthanide carboxylate supramolecular framework with nanomet...

To investigate the influences of the geometries of pendant carboxylate ligands and some intramolecular/intermolecular weak interactions on the structures of transition metal complexes, five new Cd(II) complexes, Cd2(HL1)2(L2)4 (1), Cd2(HL1)2(L3)4 (2), {[Cd2(HL1)(L4)4(H2O)2](H2O)}∞ (3), [Cd(L1)(L5)]∞ (4), and Cd2(L1)2(HL1)2(L4)2 (5) (HL1 = 3-(2-pyridyl)pyrazole, HL2 = benzoic acid, HL3 = naphthalene-carboxylic acid, HL4 = 9-anthracene-carboxylic acid, and HL5 = isonicotinic acid), have been synthesized and structurally characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analyses. 1 and 2 have a similar dinuclear structure, which is further assembled to form a one-dimensional (1D) chain by π···π stacking and/or hydrogen-bonding interactions. 3 possesses a 1D chain structure that is further interlinked via intermolecular π···π stacking, resulting in a two-dimensional (2D) network, while 4 has a 2D (4,4) network with channel dimension of 9.34 × 9.34 A2 and further assemb...

The three-dimensional Cu(II) coordination polymers [Cu(isonicotinate)2][EtOH] (1) and Cu(nicotinate)2 (2) were synthesized by treating copper nitrate with isonicotinic acid and nicotinic acid under hydro(solvo)thermal conditions, respectively. X-ray single-crystal structure determinations reveal that the Cu(II) centers in 1 adopt a slightly distorted square pyramidal geometry, while the Cu(II) centers in 2 exhibit a coordination geometry intermediate between square pyramid and trigonal bipyramid. The Cu(II) centers in 1 and 2 coordinate to both the pyridyl and carboxylate functionalities of the isonicotinate and nicotinate bridging ligands, respectively, to result in complicated 3-D framework structures. Compound 1 exhibits rhombic open channels that are occupied by removable ethanol molecules. Magnetic measurements indicated that 1 is a simple paramagnet with only very weak antiferromagnetic interactions, while 2 exhibits more pronounced antiferromagnetic interactions with J/k = −6.4 K. Crystal data for ...

One novel 3d−4f polymer, namely Gd3(IN)10(μ-OH2)6Cu5(μ2-Cl)4(H2O) (1) (HIN = isonicotinic acid), has been synthesized hydrothermally and characterized by X-ray diffraction analysis. The overall str...