scholarly journals Novel Quaternary Ammonium Derivatives of 4-Pyrrolidino Pyridine: Synthesis, Structural, Thermal, and Antibacterial Studies

Crystals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 339 ◽  
Author(s):  
Rusi Rusew ◽  
Vanya Kurteva ◽  
Boris Shivachev
Keyword(s):  
Crystal Structures ◽  
Quaternary Ammonium ◽  
Antibacterial Properties ◽  
Bacterial Strains ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Orthorhombic Crystal ◽  
One Pot ◽  
X Ray ◽  
Derivatives Of

Six novel quaternary ammonium derivatives of 4-pyrrolidino pyridine were prepared and isolated via a facile one-pot synthesis and a simple purification procedure. The purity and the molecular structure of the 4-pyrrolidino pyridine derivatives were confirmed with 1H and 13C NMR spectroscopy and powder X-ray diffraction techniques. The crystal structures of the compounds were characterized by single crystal X-ray diffraction (SCXRD) and their thermal properties were studied by Differential Scanning Calorimetry (DSC) analyses. The antibacterial properties of the title compounds against five bacterial strains were evaluated using Kirby–Bauer disk diffusion susceptibility test. The compounds crystallize in the monoclinic or orthorhombic crystal systems (space groups: P21/c, P21/n, or P212121) and their crystal structures are stabilized by a combination of intra- and intermolecular halogen bonding interactions, short contacts and π-π interactions. Above interactions, they contribute to the thermal stability and lack of phase transition effects up to 350 °C. Two of the compounds possess antibacterial effect against E. coli or S. aureus bacterial strains—similar or better than the kanamycin reference.

Phase behaviour and crystal structures of 2′,3′-difluorinated p-terphenyl derivatives

2021 ◽  
Vol 77 (7) ◽  
Author(s):  
Sakuntala Gupta ◽  
Partha Pratim Das ◽  
Przemysław Kula ◽  
Emmanuele Parisi ◽  
Roberto Centore
Keyword(s):  
Crystal Structures ◽  
Crystal Packing ◽  
Phase Behaviour ◽  
Dsc Analysis ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Space Group ◽  
X Ray ◽  
Independent Molecules ◽  
Derivatives Of

The crystal structures of difluorine derivatives of p-terphenyls (nTm) have been determined by single-crystal X-ray diffraction. For the unsymmetrical substituted compounds 2′,3′-difluoro-4-methyl-p-terphenyl (1T0, C19H14F2) and 4-ethyl-2′,3′-difluoro-4′′-methyl-p-terphenyl (1T2, C21H18F2), the crystal structure is disordered, with molecules statistically entering the crystal in up and down orientations, with full superposition of all the atoms, except for those of the terminal groups (H/methyl for 1T0 and methyl/ethyl for 1T2). For triclinic 2′,3′-difluoro-4,4′′-dimethyl-p-terphenyl (1T1, C20H16F2), with the space group P\overline{1}, the two crystallographically independent molecules have the same conformation, which is different from monoclinic 1T0 (space group C2) and 1T2 (space group C2/c). A common feature of the conformation of the three compounds is the noncoplanar twisted arrangement of the three rings of the p-terphenyl moiety. Two-dimensional (2D) Hirshfeld fingerprint plots are consistent with H...H and C...H contacts in the crystal packing. For the three compounds, the phase behaviour has been investigated by POM (Petra/Osiris/Molinspiration) and differential scanning calorimetry (DSC) analysis. 1T2 is mesogenic, with enantiotropic nematic behaviour.

The Crystal Structures at 10 K of the Trigonal Salts KMIII(NH3)6(ClO4)2Cl2, MIII = Os and Cr, and the Possibility of Phase Transitions

1999 ◽  
Vol 52 (3) ◽  
pp. 219 ◽  
Author(s):  
Philip A. Reynolds ◽  
Brian N. Figgis ◽  
Alexander N. Sobolev
Keyword(s):  
Differential Scanning Calorimetry ◽  
Transition Temperature ◽  
Crystal Structures ◽  
Low Temperatures ◽  
Simple Structure ◽  
Alkali Metal Cations ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Threefold Axis ◽  
X Ray

The crystal structures of KOs(NH3)3(ClO4)2Cl2 and KCr(NH3)6(ClO4)2Cl2 were determined at 10 K by X-ray diffraction, and for the osmium salt also at 293 K. At 293 K the osmium salt is trigonal, space group R 3m, with the same simple structure as others of this class of double salt. At 10 K, in agreement with previous radius ratio predictions, both crystals are best described as remaining R 3m. All previously studied members, with larger alkali metal cations, are twinned R 3 at low temperatures, with small, symmetry-breaking rotations of the hexaamminemetal(III) and perchlorate ions about the threefold axis. Differential scanning calorimetry on CsRu(NH3)6(ClO4)2Cl2 suggests that the R 3m to R 3 change is very extended in temperature with only a small discontinuity at the transition temperature.

New crystal structures in the realm of 5,5′-azotetrazolates

2015 ◽  
Vol 70 (2) ◽  
pp. 125-134 ◽  
Author(s):  
Martin Lampl ◽  
Gerhard Laus ◽  
Doris E. Braun ◽  
Volker Kahlenberg ◽  
Klaus Wurst ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Single Crystal ◽  
Crystal Structures ◽  
Organic Cations ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Diffraction Patterns

AbstractThe preparation of six new 5,5′-azotetrazolates with organic cations is reported. Differential scanning calorimetry of all compounds showed exothermic decompositions. The crystal structures of the six 5,5′-azotetrazolates were determined by single-crystal X-ray diffraction analyses. The phase purities of the bulk samples were confirmed by Pawley fits of the experimental and calculated powder X-ray diffraction patterns.

Adamantane derivatives of sulfonamide molecular crystals: structure, sublimation thermodynamic characteristics, molecular packing, and hydrogen bond networks

CrystEngComm ◽  
2015 ◽  
Vol 17 (4) ◽  
pp. 753-763 ◽  
Author(s):  
German L. Perlovich ◽  
Alex M. Ryzhakov ◽  
Valery V. Tkachev ◽  
Alexey N. Proshin
Keyword(s):  
Hydrogen Bond ◽  
Crystal Structures ◽  
Molecular Crystals ◽  
Thermodynamic Characteristics ◽  
Molecular Packing ◽  
Adamantane Derivatives ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrogen Bond Networks ◽  
Derivatives Of

The crystal structures of six adamantane derivatives of sulfonamides have been determined by X-ray diffraction and their sublimation and fusion processes have been studied.

Comparison of the crystal structures and thermochemistry of a novel soluble guanylate cyclase stimulator riociguat and its solvates

2017 ◽  
Vol 73 (5) ◽  
pp. 891-898 ◽  
Author(s):  
Xinbo Zhou ◽  
Xiurong Hu ◽  
Jianming Gu ◽  
Jianrong Zhu
Keyword(s):  
Crystal Structure ◽  
Thermogravimetric Analysis ◽  
Crystal Structures ◽  
Guanylate Cyclase ◽  
Soluble Guanylate Cyclase ◽  
Crystal Packing ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Soluble Guanylate Cyclase Stimulator

Riociguat (Rio) is the first oral soluble guanylate cyclase stimulator to be approved for pulmonary arterial hypertension. In this study, form (II) of riociguat and three solvates with acetonitrile [form (III)],N,N-dimethylformamide [form (IV)] and ethyl acetate [form (V)] were crystallized. They were identified and characterized by differential scanning calorimetry, thermogravimetric analysis, X-ray powder diffraction, and their crystal structures were determined by single-crystal X-ray diffraction. No crystal structure has previously been reported for the known form (II) of riociguat. Crystal structure determination of Rio and its new solvates revealed that the dimericR22(14) motif is common in both structures. The crystal packing of solvates adopts channel-like patterns, whereas form (II) of riociguat adopts sheet-like patterns. Strong π–π interactions exist in the above four forms. The conformation of the riociguat in one molecule of 0.5-DMF solvate was found to be significantly different from the conformations found in the other solvates. Desolvation of the three solvates was studied by thermogravimetric analysis and X-ray diffraction, and was shown to transform them into form (I) of riociguat.

Synthesis and properties of pyrazine-based oligomeric phthalonitrile resins

2019 ◽  
Vol 31 (9-10) ◽  
pp. 1075-1084 ◽  
Author(s):  
Yao Liu ◽  
Puguang Ji ◽  
Zhenjiang Zhang ◽  
Xiaoyan Yu ◽  
Kimiyoshi Naito ◽  
...  
Keyword(s):  
Complex Viscosity ◽  
Resonance Spectroscopy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
One Pot ◽  
X Ray ◽  
Tetragonal System ◽  
End Capping ◽  
Initial Storage ◽  
Reaction Activation Energy

The pyrazine-based oligomeric phthalonitrile (PN) monomer, 2,6-bis[3-(3,4-dicyanophenoxy)phenoxy]pyrazine (BCPP), was synthesized from the reaction of an excess amount of resorcinol with 2,6-dichloropyrazine in the presence of potassium carbonate, followed by end-capping with 4-nitrophthalonitrile in a two-step, one-pot reaction. 4-(Aminophenoxy)phthalonitrile was applied to promote the curing reaction. The curing behavior was investigated by differential scanning calorimetry and rheological behavior, showing a wide processing window of 94°C, a complex viscosity of less than 1.5 Pa·s and a lower reaction activation energy of 32.57 kJ mol−1. The structure of the BCPP monomer was confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The unit cell was determined to be tetragonal system by wide-angle X-ray diffraction. The monomer was cured to yield cross-linked polymers, which exhibited a high initial storage modulus, excellent glass transition temperature, outstanding thermal stability, and low water uptake.

Metallkomplexe mit biologisch wichtigen Liganden, CIV [1]. ortho-Palladierte Komplexe von N,N-Dimethyl-C-phenyl-glycinmethylester. Synthese von α-Aminosäure-Derivaten durch Insertion von Isocyaniden, CO, Alkenen und Alkinen in die Pd-C-Bindung / Metal Complexes of Biologically Important Ligands, CIV [ 1]. ortho-Palladated Complexes of N,N-Dimethyl-C-phenylglycine-methylester. Synthesis of α-Amino Acid Derivatives by Insertion of Isocyanides, CO, Alkenes, and Alkynes into the Pd-C Bond

1998 ◽  
Vol 53 (4) ◽  
pp. 448-458 ◽  
Author(s):  
Andreas Böhm ◽  
Kurt Polborn ◽  
Karlheinz Sünkel ◽  
Wolfgang Beck
Keyword(s):  
Acetic Acid ◽  
Amino Acid ◽  
Metal Complexes ◽  
Crystal Structures ◽  
Trinuclear Complex ◽  
Amino Acid Derivatives ◽  
X Ray Diffraction ◽  
X Ray ◽  
Derivatives Of ◽  
Amine Ligand

Abstract N,N-Dimethyl-C-phenylglycinemethylester reacts with Pd(OAc)2 in acetic acid to give the orthopalladated, acetato bridged complex 1. Treatment of 1 with sodium halide affords the chloro, bromo, and iodo bridged compounds [Me2NC(H)(CO2Me)C6H4PdX]2 (2a -c) (X = halide). From 2a and 1,1′-bis(diphenylphosphino)ferrocene the phosphine bridged trinuclear complex 3 is obtained. Substitution of the amine ligand of 2a by the phosphino group is observed for the reaction of 2a with Ph2PC(Me)C(Me)PPh2. Insertion of 2,6-dimethyl-phenylisocyanide, CO, alkyl-vinyl-ketones, and diphenylacetylene into the Pd-C bond o f 2a -c provides the orthosubstituted organic and organometallic derivatives of phenylglycine 6a -c, 7, 8a -b and 9a -c. The crystal structures of 1, 4a, 6a, 7 and 9a were determined by X-ray diffraction.

Ethene-1,1,2,2-tetracarbonitrile and Methanol in the Methylating Reaction of Tertiary Amines to the Quaternary Ammonium Compounds of 1,1-Dicyano-2-methoxy-2-oxoethane-1-ide

Synlett ◽  
2018 ◽  
Vol 30 (02) ◽  
pp. 173-177
Author(s):  
Vladimir Р. Sheverdov ◽  
Vera Davydova ◽  
Oleg Nasakin ◽  
Maksim Mar’yasov ◽  
Olga Lodochnikova
Keyword(s):  
Diffraction Analysis ◽  
Crystal Structures ◽  
Quaternary Ammonium ◽  
Room Temperature ◽  
Quaternary Ammonium Compounds ◽  
Tertiary Amines ◽  
X Ray Diffraction ◽  
X Ray ◽  
Methanol Solutions ◽  
Ammonium Compounds

We discovered a new method to methylate tertiary amines such as urotropine, triethylamine, pyridine, 2-methylpyridine, 4-acetylpyridine, and isonicotinamide, up to quaternary ammonium compounds, with 1,1-dicyano-2-methoxy-2-oxoethane-1-ide being the counterion. Methyl-1,3,5,7-tetraazaadamantan-1-ium 1,1-dicyano-2-methoxy-2-oxoethane-1-ide, N,N-diethyl-N-methylethanaminium 1,1-dicyano-2-methoxy-2-oxoethane-1-ide, and substituted-methylpyridinium 1,1-dicyano-2-methoxy-2-oxoethane-1-ides were synthesized. Quaternary ammonium compounds of 1,1-dicyano-2-methoxy-2-oxothane-1-ide were synthesized within a single stage by stirring methanol solutions of tertiary amines with ethene-1,1,2,2-tetracarbonitrile (ETCN) at room temperature. In the reaction of ETCN with tertiary amines in methanol, processes occur that form the 1,1-dicyano-2-methoxy-2-oxoethane-1-ide fragment with simultaneous N-methylation. Crystal structures based on X-ray diffraction analysis of the obtained compounds were studied.

Structural studies in the iron(III)/chloride/α,α'-diimine system. II. Ionic derivatives of stoichiometry FeCl3(phen,bpy)1,1.5

1983 ◽  
Vol 36 (10) ◽  
pp. 2043 ◽  
Author(s):  
BN Figgis ◽  
JM Patrick ◽  
PA Reynolds ◽  
BW Skelton ◽  
AH White ◽  
...  
Keyword(s):  
Single Crystal ◽  
Least Squares ◽  
Crystal Structures ◽  
Acetonitrile Solution ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Determinations ◽  
Derivatives Of

The crystal structures of the 1 : 1 adducts of FeCl3 with 2,2'-bipyridine (bpy) (1) and 1,10-phenanthroline (phen) (2), as recrystallized from nitromethane, have been determined by single-crystal X-ray diffraction methods at 295 K, being refined by least squares to residuals of 0.038 and 0.032 for 1341 and 3968 'observed' reflections; the result for (2) is a redetermination. Crystals of (1) are orthorhombic, Pbnb, a 15.013(4), b 13.510(5), c 12.471(3) Ǻ, Z 4. Crystals of (2) are triclinic, P1, a 15.823(5), b 11.021(5), c 8.200(3) Ǻ, α 80.27(3), β 76.78(3), γ 89.64(3)°, Z 2. Both complexes haw the stoichiometry (FeCl3)1(bpy,phen)1, but are formulated as cis-[Fe(bpy,phen)2Cl2] [FeCl4]; in both compounds, the Fe-N distance is c. 2.20, (trans to Cl), 2.1, Ǻ(cis to Cl), while Fe-Cl, c. 2.2, Ǻ, is short. The structure determinations of Fe2Cl6(phen,bpy)3 as [Fe(phen)2Cl2]+ [Fe(phen)Cl4]- (3) and [Fe(bpy)2Cl2]+ [Fe(bpy)Cl4]- (4) are also reported. Compound (3) (from acetonitrile solution) is triclinic, P1, a 16.502(5), b 11.857(3), c 10.653(3) Ǻ, α 84.92(2), β 72.66(2), γ 74.80(2)°, Z 2, and was refined to a residual of 0.034 for 5540 'observed' reflections. The cation geometry is similar to that of (2); in the anion, the two Fe-CI bonds trans to each other are long [2.377(1) and 2.365(1) Ǻ] while those trans to the Fe-N bonds are short [2.287(1) and 2.318(1) Ǻ]. Fe-N distances are 2.216(3) and 2.220(3) A. Compound (4) (as its nitromethane solvate) is also triclinic, P1, a 14.480(7), b 12.645(5), c 10.678(4) Ǻ, α 95.68(3), β 109.21(3), γ 9258(3)°, Z 2; a residual of 0.042 was obtained for 4962 'observed' reflections. Cation and anion metal geometries are similar to those of (3).

scholarly journals Phase Transitions and Crystal Structures of Ni(II) Complexes Determined with X-ray Powder Diffraction Data

Crystals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 106 ◽  
Author(s):  
Hisashi Konaka ◽  
Akito Sasaki
Keyword(s):  
Differential Scanning Calorimetry ◽  
Crystal Structures ◽  
Structural Changes ◽  
Original Form ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Hydrate Form ◽  
X Ray ◽  
Dsc Measurements ◽  
Crystalline Forms

Structural changes of chloride and bromide complexes, [Ni(Et2en)2(H2O)2]Cl2 (designated as 1a) and [Ni(Et2en)2]Br2 (2a), have been investigated by using simultaneous measurements of powder X-ray diffraction (XRD) and differential scanning calorimetry data under the temperature and humidity controls. The hydrate form of chloride complex 1a was transformed into an anhydrate form (1b) by heating at a temperature of 361 K. Then the 1b was reversibly returned to the original 1a by humidification at 25% relative humidity (RH) and temperature of 300 K. On the other hand, the anhydrate form of the bromide complex 2a was first transformed into a hydrate form (2b) at 30% RH and 300 K. On heating, the 2b turned to a new anhydrate form (2c) at 344 K, and then it returned to the original form 2a on further heating. In the present experiments, a series of reactions of 2a proceeded via 2c, which was newly found with the benefit of differential scanning calorimetry (DSC) measurements performed in parallel to the XRD measurements. Crystal structures of new crystalline forms of 1b, 2b, and 2c were determined from the powder XRD data.

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