Synthesis, structures and Hirshfeld surface analyses of 2-hy-droxy-'-methyl-acetohydrazide and 2-hy-droxy--methyl-acetohydrazide.

The structures of the title compounds 2-hy-droxy-'-methyl-acetohydrazide, , and 2-hy-droxy--methyl-acetohydrazide, , both CHNO, as regioisomers differ in the position of the methyl group relative to the N atoms in 2-hy-droxy-acetohydrazide. In the structure of , the 2-hy-droxy-acetohydrazide core [OH-C-C(=O)-NH-NH] is almost planar and the methyl group is rotated relative to this plane. As opposed to , in the structure of all non-hydrogen atoms lie in the same plane.

Supramolecular architecture of theophylline polymorphs, monohydrate and co-crystals with iodine: study from the energetic viewpoint.

The regularities of crystal structure organization were thoroughly studied in all to date known polymorphic modifications of theophylline (THP) using an energetic approach. The monohydrate and a co-crystal of theophylline with one half equivalent of an iodine molecule were similarly investigated. The calculations of pairwise interaction energies have showed that the crystals studied can be divided into two groups according to their basic structural motifs: or .

Crystal structure and Hirshfeld surface analysis of di-chlorido-[2-(3-cyclo-pentyl-1,2,4-triazol-5-yl-κ )pyridine-κ]palladium(II) di-methyl-formamide monosolvate.

This study presents the synthesis, characterization and Hirshfeld surface analysis of the title mononuclear complex, [PdCl(CHN)]·CHNO. The compound crystalizes in the 2/ space group of the monoclinic system. The asymmetric unit contains one neutral complex Pd(H )Cl [H is 2-(3-cyclo-pentyl-1,2,4-triazol-5-yl)pyridine] and one mol-ecule of DMF as a solvate.

3-Substituted 6-Azabicyclo[3.1.1]heptanes: Nonclassical Piperidine Isosteres for Drug Discovery.

Advanced analogs of piperidine and smaller homologues of tropane─3-substituted 6-azabicyclo[3.1.1]heptanes─were synthesized on a large scale using readily available bulk reagents.

4-Trifluoromethoxy proline: synthesis of stereoisomers and lipophilicity study.

All four stereoisomers of 4-CFO-proline have been synthesized through a fluorodesulfurization approach using the corresponding 4-hydroxyprolines as starting materials. The investigation of their lipophilicity characteristics and comparison with those of other 4-substituted proline analogs demonstrated a similar impact of CF and CFO groups on log .

Synthesis, crystal structure and Hirshfeld surface analysis of the tetra-kis complex NaNdPyr(-PrOH)·-PrOH with a carbacyl-amido-phosphate of the amide type.

The tetra-kis complex of neodymium(III), tetra-kis-{μ--[bis-(pyrrolidin-1-yl)phos-phor-yl]acet-am-id-ato}bis(pro-pan-2-ol)neodymiumsodium pro-pan-2-ol monosol-vate, [NaNd(CHClNO)(CHO)]·CHO or NaNdPyr(-PrOH)·-PrOH, with the amide type CAPh ligand bis(,-tetra-methylene)(tri-chloro-acetyl)phos-phoric acid tri-amide (HPyr), has been synthesized, crystallized and characterized by X-ray diffraction. The complex does not have the tetra-kis-(CAPh)lanthanide anion, which is typical for ester-type CAPh-based coordin-ation compounds. Instead, the NdO polyhedron is formed by one oxygen atom of a 2-propanol mol-ecule and seven oxygen atoms of CAPh ligands in the title compound.

Concomitant polymorphs of 2-imino-2H-chromene-3-carboxylic acid amide: experimental and quantum chemical study.

2-Iminocoumarin-3-carboxamide (2-imino-2 H-chromene-3-carboxylic acid) is a perspective compound for use in the pharmaceutical industry. This compound crystallized from several solvents as two concomitant polymorphic forms. The monoclinic polymorph, crystallized initially, is formed due to strong N-H.

Towards Amplified Probing of Weak Intermolecular Interactions on the External Surfaces of Molecular Capsules.

We report a sensitive method for comparing weak interactions between aryl rings located on the external surfaces of equilibrating homo- and heterodimeric capsules. Two identical self-complementary resorcin[4]arene tetrabenzoate molecules and one tetramethylammonium cation form in CDCl hydrogen-bonded homodimeric capsules whose exteriors are decorated with four tight pairs of weakly interacting aryl rings. The pair wise mixing of six different homodimers establishes their equilibria with the corresponding heterodimeric species in which two types of aryl rings exert on each other some gentle forces.

New Polymorphic Modifications of 6-Methyluracil: An Experimental and Quantum Chemical Study.

Polymorphism of 6-methyluracil, which affects the regulation of lipid peroxidation and wound healing, has been studied by experimental and quantum chemical methods. Two known polymorphic modifications and two new crystalline forms were crystallized and characterized by single crystal and powder X-ray diffraction (XRD) methods as well as by the differential scanning calorimetry (DSC) method and infrared (IR) spectroscopy. The calculations of pairwise interaction energies between molecules and lattice energies in periodic boundary conditions have shown that the polymorphic form used in the pharmaceutical industry and two new forms and , which can be formed due to temperature violations, may be considered as metastable.

Crystal structure and Hirshfeld surface analysis of bis-(μ-4--but-oxy-4-oxobut-2-en-2-olato)bis-[(4--but-oxy-4-oxobut-2-en-2-olato)ethano-lzinc(II)].

The mol-ecular and crystal structure of the title binuclear Zn complex, [Zn(CHO)(CHOH)], with enolated anionic -butyl-aceto-acetate and ethanol was analysed. The coordination polyhedra of the Zn atoms are distorted octa-hedra formed by six oxygen atoms that belong to three ligand mol-ecules and a coordinated ethanol mol-ecule. In the crystal phase, alternating layers can be distinguished parallel to the plane.

Synthesis, analysis of mol-ecular and crystal structures, estimation of inter-molecular inter-actions and biological properties of 1-benzyl-6-fluoro-3-[5-(4-methylcyclohexyl)-1,2,4-oxadiazol-3-yl]-7-(piperidin-1-yl)quinolin-4-one.

The title compound, CHNOF, can be obtained a two-step synthetic scheme involving 1-benzyl-6-fluoro-4-oxo-7-(piperidin-1-yl)-1,4-di-hydro-quino-line-3-carbo-nitrile as a starting compound that undergoes substitution with hydroxyl-amine and subsequent cyclization with 4-methyl-cyclo-hexane-1-carb-oxy-lic acid. It crystallizes from 2-propanol in the triclinic space group with a mol-ecule of the title compound and one of 2-propanol in the asymmetric unit. After the mol-ecular structure was clarified using NMR and LC/MS, the mol-ecular and crystalline arrangements were defined with SC-XRD.

Single Crystalline Films of Ce-Doped YMgSiAlO Garnets: Crystallization, Optical, and Photocurrent Properties.

This research focuses on LPE growth, and the examination of the optical and photovoltaic properties of single crystalline film (SCF) phosphors based on Ce-doped YMgSiAlO garnets with Mg and Si contents in x = 0-0.345 and y = 0-0.31 ranges.

Crystal structure of caesium dimethyl--benzoyl-amido-phosphate monohydrate.

The caesium salt of dimethyl--benzoyl-amido-phosphate, namely, aqua-[di-meth-yl (-benzoyl-amido-κ)phospho-nato-κ]caesium, [Cs(CHNOP)(HO)] or Cs·HO, is reported. The compound crystallizes in the monoclinic crystal system in the 2/ space group and forms a mono-periodic polymeric structure due to the bridging function of the dimethyl--benzoyl-amido-phosphate anions towards the caesium cations.

Intramolecular Charge Transfer and Ultrafast Nonradiative Decay in DNA-Tethered Asymmetric Nitro- and Dimethylamino-Substituted Squaraines.

Molecular (dye) aggregates are a materials platform of interest in light harvesting, organic optoelectronics, and nanoscale computing, including quantum information science (QIS). Strong excitonic interactions between dyes are key to their use in QIS; critically, properties of the individual dyes govern the extent of these interactions. In this work, the electronic structure and excited-state dynamics of a series of indolenine-based squaraine dyes incorporating dimethylamino (electron donating) and/or nitro (electron withdrawing) substituents, so-called asymmetric dyes, were characterized.

Exciton Chirality Inversion in Dye Dimers Templated by DNA Holliday Junction.

While only one enantiomer of chiral biomolecules performs a biological function, access to both enantiomers (or enantiomorphs) proved to be advantageous for technology. Using dye covalent attachment to a DNA Holliday junction (HJ), we created two pairs of dimers of bis(chloroindolenine)squaraine dye that enabled strongly coupled molecular excitons of opposite chirality in solution. The exciton chirality inversion was achieved by interchanging single covalent linkers of unequal length tethering the dyes of each dimer to the HJ core.

Synthesis, X-ray diffraction study, analysis of inter-molecular inter-actions and mol-ecular docking of ethyl 1-(3-tosyl-quinolin-4-yl)piperidine-4-carboxyl-ate.

The title compound, CHNOS, can be obtained two synthetic routes. According to our investigations, the most suitable way is by the reaction of ethyl 2-bromo-acetate with sodium tosyl-sulfinate in dry DMF. It was crystallized from methanol into the monoclinic 2/ space group with a single mol-ecule in the asymmetric unit.

Design, Synthesis and Biological Evaluation of Novel Promising Analgesics.

Introduction: An analysis of the literature on the painkillers long used in traditional medicine, which are isolated from plant materials, has shown that many of them are alkylamides of various carboxylic acids. This fact served as the basis for the study of a large group of N-alkyl-4- methyl-2,2-dioxo-1H-2λ,1-benzothiazine-3-carboxamides as potential new analgesics. The objects of the study were synthesized in the traditional way involving the initial conversion of 4-methyl- 2,2-dioxo-1H-2λ,1- benzothiazine-3-carboxylic acid to imidazolide, in which imidazolide was used as an acylating agent.

Polymorphic transition due to grinding: the case of 3-[1-(tert-butoxycarbonyl)azetidin-3-yl]-1,2-oxazole-4-carboxylic acid.

A polymorphic transition as a result of grinding was found for 3-[1-(tert-butoxycarbonyl)azetidin-3-yl]-1,2-oxazole-4-carboxylic acid. The thorough study of polymorphic structures before and after crystal structure transformation has revealed some pre-conditions for a polymorphic transition and regularities of changes in molecular and crystal structure. In metastable polymorph 1a, the conformationally flexible molecule adopts a conformation with the higher energy and forms a less preferable linear supramolecular synthon.

Quantum Chemical Study on Mefenamic Acid Polymorphic Forms.

Three polymorphic structures of mefenamic acid, which is a very popular drug, have been studied using quantum chemical methods. It has been shown that the centrosymmetric dimer formed due to two O-H···O hydrogen bonds is a complex building unit in all of the polymorphic structures under study. On the basis of an analysis of the pairwise interaction energies between molecules, the polymorphic forms and are classified as columnar-layered while the polymorphic form has a columnar structure.

4-[(Benzyl-amino)-carbon-yl]-1-methyl-pyridinium bromide hemihydrate: X-ray diffraction study and Hirshfeld surface analysis.

The hemihydrate of 4-[(benzyl-amino)-carbon-yl]-1-methyl-pyridinium bromide, CHNO·Br·0.5HO, was studied by single-crystal and powder X-ray diffraction methods. In the asymmetric unit, two organic cations of similar conformation, two bromide anions and one water mol-ecule are present.

First-principles studies of substituent effects on squaraine dyes.

Dye molecules that absorb light in the visible region are key components in many applications, including organic photovoltaics, biological fluorescent labeling, super-resolution microscopy, and energy transport. One family of dyes, known as squaraines, has received considerable attention recently due to their favorable electronic and photophysical properties. In addition, these dyes have a strong propensity for aggregation, which results in emergent materials properties, such as exciton delocalization.

Hybrid Cu-Containing Compounds Based on Lacunary Strandberg Anions: Synthesis under Mild Conditions, Crystal Structure, and Magnetic Properties.

A one-pot reaction of a copper source (metallic powder Cu or Cu salts) and bpy (bpy = 2,2'-bipyridine) in the presence of (NH)HPO and (NH)MoO·4HO yields heterometallic hybrid compounds of the general type {[Cu(bpy)(HO)][PMoO]}. The structures exhibit a number of phosphomolybdate POMs including not only a common Strandberg anion [PMoO] but also its unprecedented bi- and trilacunary derivatives [PMoO] and [PMoO]. The structural determinants including the metal source (copper powder copper salts), counterion of the salts, and stoichiometry of the reagents were examined.

4-[(Benzyl-amino)-carbon-yl]-1-methyl-pyridinium halogenide salts: X-ray diffraction study and Hirshfeld surface analysis.

Two salts of 4-[(benzyl-amino)-carbon-yl]-1-methyl-pyridinium () with chloride (CHNO·Cl) and bromide (CHNO·Br) anions were studied and compared with the iodide salt. crystallizes in the centrosymmetric space group 2/ while and form crystals in the Sohncke space group 222. Crystals of are isostructural to those of .

1-Allyl-4-hydroxy-2,2-dioxo-N-(4-methoxyphenyl)-1H-2λ,1-benzothiazine-3-carboxamide: polymorphic transition due to grinding with the loss of the biological activity.

A study of two polymorphic forms of 1-allyl-4-hydroxy-2,2-dioxo-N-(4-methoxyphenyl)-1-2λ,1-benzothiazine-3-carboxamide (a structural analogue of piroxicam) has revealed some regularities in the crystal structure formation due to different evaporation rates from the tested solvents. The monoclinic polymorph crystallized from ethyl acetate is formed due to a large number of very weak C-H..