scholarly journals Synthesis of mono and bis-substituted asymmetrical compounds, (1-(pyridin-2-yl)ethylidene)carbonohydrazide and 1-(2'-hydroxybenzylidene)-5-(1'-pyridylethylidene)carbonohydrazone: Structural characterization and antioxidant activity study

2020 ◽  
Vol 11 (4) ◽  
pp. 285-290
Author(s):  
Thierno Moussa Seck ◽  
Fatou Dieng Faye ◽  
Aissatou Alioune Gaye ◽  
Ibrahima Elhadji Thiam ◽  
Ousmane Diouf ◽  
...  

Carbonohydrazide was used for synthetizing a new dissymmetrical bis-substituted Schiff base 1-(2'-hydroxybenzylidene)-5-(1'-pyridylethylidene)carbonohydrazone (2). A mono substituted compound (1-(pyridin-2-yl)ethylidene)carbonohydrazide (1) was firstly prepared by condensation reaction of carbonohydrazide and 2-acetylpyridine in 1:1 ratio. Secondly, compound 2 was obtained by condensation reaction of compound 1 and salicylaldehyde in 1:1 ratio. The prepared compounds were characterized by elemental analysis, infrared and 1H and 13C NMR spectroscopy techniques, and the structure of compound 2 was determined by single-crystal X-ray diffraction study. The compound 2 (C15H15N5O2) crystallises in the monoclinic space group P21/c with the following unit cell parameters: a = 8.3683(3) Å, b = 13.9986(4) Å, c = 12.1610(4) Å, β = 97.512(3)°, V = 1412.37(8) Å3, Z = 4, T = 100(2) K, μ(MoKα) = 0.098 mm-1, Dcalc = 1.398 g/cm3, 6057 reflections measured (5.708° ≤ 2Θ ≤ 54.962°), 6057 unique (Rsigma = 0.0395) which were used in all calculations. The final R1 was 0.0474 (I > 2σ(I)) and wR2 was 0.1971 (all data). The oxygen atom O1 and the azomethine nitrogen atom N5 adopt cis-configuration relative to the C8-N4 bond, while O1 adopts trans-configuration with the azomethine nitrogen atom N2 relative to C8-N3 bond. The crystal packing of compound 2 is stabilized by intramolecular O(phenol)–H···N(carbohydrazide) and intermolecular N (carbohydrazide)–H···O (carbo-hydrazide) hydrogen bonds which form layers parallel to [010] axis. Additional C–H···O hydrogen bond consolidate the structure. The carbonohydrazide moiety C=N–N–C(O)–N–N=C fragment and the phenyl ring are almost coplanar; with an angle of 1.73(1)° between their means plans. The dihedral angle between the mean planes of the phenyl and the pyridine rings is 22.267(2)°.

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Tetsuji Moriguchi ◽  
Tatsuya Egami ◽  
Akihiko Tsuge

A large calixarene-like metacyclophane, 4′,9′,4″,9″-tetra-tert-butyl-1′,6′,1″,6″-tetramethoxy-2,5-dioxa[3.3]metabiphenylophane, was synthesized by an intermolecular condensation reaction of its corresponding bischloromethyl-biphenyl and bishydroxymethyl-biphenyl precursors. After molecular characterization by 1H NMR spectroscopy and mass spectrometry, the compound generated single crystals by recrystallization from a dichloromethane/hexane mixture, facilitating an exact conformational determination via X-ray diffraction analysis. The crystal was found to belong to the monoclinic space group P21/n with cell parameters a = 19.908(2) Å, b = 9.7193(11) Å, c = 23.350(3) Å, β = 109.594(1)°, and Dcalc=1.150 g/cm3 at 90 K. The compound adopted quite strained 1,2-alternate-like conformations because its biphenyl parts displayed large dihedral angles and rigidity. The crystal did not incorporate any solvent molecule but its molecular cavity and crystal space were effectively filled by the substituents.


Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5320
Author(s):  
Shouting Wu ◽  
Xi Liang ◽  
Fang Luo ◽  
Hua Liu ◽  
Lingyi Shen ◽  
...  

A phenazine-1-carboxylic acid intermediate was synthesized from the reaction of aniline and 2-bromo-3-nitro-benzoic acid. It was then esterified and reacted with hydrazine hydrate to afford phenazine-1-carboxylic hydrazine. Finally, 10 new hydrazone compounds 3a–3j were obtained by the condensation reaction of phenazine-1-carboxylic acid hydrazide and the respective aldehyde-containing compound. The structures were characterized by 1H and 13C NMR spectroscopy, MS and single crystal X-ray diffraction. The antitumor activity of the target compounds in vitro (HeLa and A549) was determined by thiazolyl blue tetrazolium bromide. The results showed that compound (E)-N′-(2-hydroxy-4-(2-(piperidine-1-yl) ethoxy) benzyl) phenazine-1-carbonyl hydrazide 3d exhibited good cytotoxic activity.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Youssef Kandri Rodi ◽  
Santiago V. Luis ◽  
Inés Martí ◽  
Vicente Martí-Centelles ◽  
Younès Ouzidan

The crystal and molecular structure of 6-bromo-2-(furan-2-yl)-3-(prop-2-ynyl)-3H-imidazo[4,5-b]pyridine (C13H8BrN3O) has been investigated from single crystal X-ray diffraction data. The primary focus is to investigate the molecular geometry of this compound in the solid state along with the associated intermolecular hydrogen bonding and relatedπ-πinteractions present in the crystal packing. This compound crystallizes in the monoclinic space groupP21/nwith cell parameters:a= 4.39655(19) Å,b= 13.5720(5) Å,c= 20.0471(5) Å,β= 94.753(3),V= 1192.10(7) Å3,D= 1.683 g·cm−3, andZ= 4. The crystal structure is stabilized byπ-πinteractions and intermolecular C–H⋯N and C–H⋯O interactions.


2008 ◽  
Vol 3 (2) ◽  
pp. 119-121
Author(s):  
Diana Dragancea ◽  
Vladimir B. Arion ◽  
Sergiu Shova

The new ligand, bis(2-hydroxybenzaldehyde)diaminoguanizone (1) has been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopies. The crystal structure of the compound was determined by X-ray diffraction. The ligand C15H15N5O2·C2H5OH crystallizes in the monoclinic space group P21/c with unit cell parameters a = 8.9102(3), b = 10.0357(3), c = 19.7618(6) Å, β = 98.385(2)°, Z = 4, V = 1748.21(9) Å3, R1 = 0.040. The amino form of the ligand adopts a planar conformation stabilized by two intramolecular hydrogen bonds of the type O–H···N, in which the H atoms of the central amino group are directed to the lone-pair regions of the azomethine nitrogen atoms.


2019 ◽  
Vol 16 (32) ◽  
pp. 812-819
Author(s):  
G. DELGADO ◽  
M. GUILLEN ◽  
A. J. MORA

Polymorphism is known as the ability of a solid material to exist in more than one form or crystal structure, with important applications in the preparation of active pharmaceutical ingredients. Characterization of different polymorphs of the specific metabolite of 4-xylene can contribute to the chemical and pharmaceutical industry. Polymorphism is of particular importance in industrial processes, where different physical properties of polymorphic forms can substantially alter the viability and quality of a manufactured product. This is particularly so for the design and production of drugs in the pharmaceutical industry, as varying physical properties between different polymorphs can affect shelf life and durability, solubility, as well as bioavailability and manufacturing of the drug. The crystallization, spectroscopic and X-ray diffraction characterization of two polymorph and one solvatomorph of 4-methylhippuric acid are presented. These compounds crystallizes in different crystalline systems. Polymorph I (4mH-I) crystalize in an orthorhombic cell with space group P212121. Polymorph II (4mHII) crystallizes in a monoclinic space group P21/c. Solvatomorph (4mH-S) crystallizes in a triclinic P-1 cell. All polymorphs crystallize in neutral form. The crystal packing of the three compounds are governed by hydrogen bonds intermolecular interactions of the type N--H···O and O--H···O forming tridimensional networks.


Author(s):  
Inês B. Trindade ◽  
Bruno M. Fonseca ◽  
Pedro M. Matias ◽  
Ricardo O. Louro ◽  
Elin Moe

Siderophore-binding proteins (SIPs) perform a key role in iron acquisition in multiple organisms. In the genome of the marine bacteriumShewanella frigidimarinaNCIMB 400, the gene tagged as SFRI_RS12295 encodes a protein from this family. Here, the cloning, expression, purification and crystallization of this protein are reported, together with its preliminary X-ray crystallographic analysis to 1.35 Å resolution. The SIP crystals belonged to the monoclinic space groupP21, with unit-cell parametersa= 48.04,b= 78.31,c= 67.71 Å, α = 90, β = 99.94, γ = 90°, and are predicted to contain two molecules per asymmetric unit. Structure determination by molecular replacement and the use of previously determined ∼2 Å resolution SIP structures with ∼30% sequence identity as templates are ongoing.


Author(s):  
M. Rajasekar ◽  
K. Muthu ◽  
A. Aditya Prasad ◽  
R. Agilandeshwari ◽  
SP Meenakshisundaram

Single crystals of molybdenum-incorporated tris(thiourea)zinc(II) sulfate (MoZTS) are grown by the slow evaporation solution growth technique. Crystal composition as determined by single-crystal X-ray diffraction analysis reveals that it belongs to the orthorhombic system with space groupPca21and cell parametersa= 11.153 (2),b= 7.7691 (14),c= 15.408 (3) Å,V= 1335.14 (4) Å3andZ= 4. The surface morphological changes are studied by scanning electron microscopy. The vibrational patterns in FT–IR are used to identify the functional group and TGA/DTA (thermogravimetric analysis/differential thermal analysis) indicates the stability of the material. The structure and the crystallinity of the material were confirmed by powder X-ray diffraction analysis and the simulated X-ray diffraction (XRD) closely matches the experimental one with varied intensity patterns. The band gap energy is estimated using diffuse reflectance data by the application of the Kubelka–Munk algorithm. The relative second harmonic generation (SHG) efficiency measurements reveal that MoZTS has an efficiency comparable to that of tris(thiourea)zinc(II) sulfate (ZTS). Hirshfeld surfaces were derived using single-crystal X-ray diffraction data. Investigation of the intermolecular interactions and crystal packingviaHirshfeld surface analysis reveal that the close contacts are associated with strong interactions. Intermolecular interactions as revealed by the fingerprint plot and close packing could be the possible reasons for facile charge transfer leading to SHG activity.


1997 ◽  
Vol 52 (10) ◽  
pp. 1229-1236 ◽  
Author(s):  
Dagmar Henschel ◽  
Karna Wijaya ◽  
Oliver Moers ◽  
Armand Blaschette ◽  
Peter G. Jones

The complex compounds 4HN (SO2Me)2 · (diaza-18-crown-6) (1) and Na[N(SO2Ph)2] · 2HN(SO2Ph)2 · 2 (12-crown-4) · 2 MeOH (2) were obtained from their components and characterized by low-temperature X-ray diffraction. Structure 1 (monoclinic, space group P21/n) displays centrosymmetric formula units consisting of a biangular diazonia-18-crown-6 dication, two (MeSO2)2N− anions situated above and below the macrocycle and linked to the NH2+ groups via an N - H ··· O and N -H ··· N bond system, and finally two HN(SO2Me)2 molecules, each forming an N -H ··· O bond to one of the anions. The molecule-anion entity represents an iso form of the [(RSO2)2N -H ··· N (SO2R)2]− homoconjugates previously described. The crystal packing of 1 is stabilized by an extensive and highly organized [H2C -H ··· O(S)] hydrogen bond network. Structure 2 (monoclinic, space group P21/n) exhibits inconspicuous [Na(12-crown-4)2]+ cations and, as a striking feature, supramolecular anions assembled from a central (PhSO2)2N− ion, two MeOH molecules flanking the amide anion, and two HN (SO2Ph)2 molecules bonded to the MeOH moieties. The assembly is held together by two N -H ··· O(H )(Me) bonds, one MeO -H ··· N− bond and one MeO -H ··· O(anion) interaction. For both structures, conformational peculiarities of the N(SO2C)2 groups are discussed.


2005 ◽  
Vol 20 (4) ◽  
pp. 311-315 ◽  
Author(s):  
M. Ramírez-Cardona ◽  
L. Ventolà ◽  
T. Calvet ◽  
M. A. Cuevas-Diarte ◽  
J. Rius ◽  
...  

In the course of our research on normal alkanols, the crystal structure of 1-pentanol has been solved by applying Patterson-search methods to laboratory powder X-ray diffraction data recorded on a curved position-sensitive detector (CPS120) at 183 K. The crystal structure was refined with the rigid-body Rietveld least-squares method. The cell is monoclinic, space group P21∕c, Z=4, and the cell parameters are a=15.592(9) Å, b=4.349(1) Å, c=9.157(1) Å, β=104.7(7)°, V=600.6(3) Å3. There is one molecule in the asymmetric unit with the O–H bond in gauche conformation with respect to the alkyl skeleton. Packing is defined by the hydrogen bonds linking the 1-pentanol molecules along zigzag chains parallel to b.


2015 ◽  
Vol 68 (3) ◽  
pp. 357 ◽  
Author(s):  
Kevin P. Yeagle ◽  
Darryl Hester ◽  
Nicholas A. Piro ◽  
William G. Dougherty ◽  
W. Scott Kassel ◽  
...  

The aluminium complexes {[κ2-N,O-(t-BuNCOPh)]AlMe2}2 (2), [κ2-N,O-(t-BuNCOPh)]2AlMe (3), and [κ2-N,O-(t-BuNCOPh)]3Al (4) were prepared through the protonolysis reaction between trimethylaluminium and one, two, or three equivalents, respectively, of N-tert-butylbenzamide. Complex 2 was also prepared via a salt metathesis reaction between K(t-BuNCOPh) and dimethylaluminium chloride. Complexes 2–4 were characterized using 1H and 13C NMR spectroscopy. Single-crystal X-ray diffraction analysis of the complexes corroborated ligand : metal stoichiometries and revealed that all the amidate ligands coordinate to the aluminium ion in a κ2 fashion. The Al–amidate complexes 2–4 were viable catalyst precursors for the Meerwein–Ponndorf–Verley–Oppenauer reduction–oxidation manifold, successfully interconverting several classes of carbonyl and alcohol substrates.


Sign in / Sign up

Export Citation Format

Share Document