Synthesis, 2D NMR and X-ray diffraction studies on Cu(II) and Ni(II) complexes with ligands derived from azobenzene-cored Schiff base: Mesomorphic behaviors of Cu(II)–phenolates and crystal structure of bis[4-(4-alkoxy-2-hydroxybenzylideneamino)azobenzene]copper(II)

2011 ◽  
Vol 999 (1-3) ◽  
pp. 68-82 ◽  
Author(s):  
Guan-Yeow Yeap ◽  
Boon-Teck Heng ◽  
Masaki Kakeya ◽  
Daisuke Takeuchi ◽  
Ewa Gorecka ◽  
...  
2021 ◽  
Author(s):  
SOUMYA SUNDAR MATI ◽  
Dr. SAUGATA KONAR ◽  
BOBY SAMAI

A zinc coordinated rare binuclear complex was synthesised and characterized by elemental analysis and single-crystal X-ray diffraction. Two mononuclear units formed by two Schiff base ligands 2-((2-(pyrimidin-2-yl)hydrazono)methyl)phenol (PHP) coordinated with...


2018 ◽  
Vol 74 (11) ◽  
pp. 1440-1446
Author(s):  
Qi Zhang ◽  
Li Ma ◽  
Zhaoxia Qu ◽  
Guige Hou ◽  
Yanan Wang ◽  
...  

Two new isodaucane-type sesquiterpenoids, namely (1R,4S,5S,6R,7S,10R)-isodauc-6,7,10-triol, C15H28O3, (1), and (1R,4S,5S,6S,7S,10R)-isodauc-6,7,10-triol, (2), and a new eudesmane-type sesquiterpenoid, 1β,4β,5α-trihydroxyeudesmane, (3), were obtained from the rhizomes of homalomena occulta with the aid of column chromatography. Their structures were elucidated based on extensive spectroscopic analyses, including 1D NMR, 2D NMR and HRESIMS. The structure of (1) was confirmed by single-crystal X-ray diffraction and the absolute configuration was assigned with respect to that of the precursor. The single-crystal structure reveals that adjacent molecules of (1) embrace through two groups of intermolecular O—H...O hydrogen bonds to generate a two-dimensional sheet with a 63-net topology. The three compounds were evaluated for their activity against lipopolysaccharide-induced production of nitrogen oxide (NO) in RAW 264.7 cells, and (1) showed an inhibitory effect on NO production, with IC50 values of 5.7±0.22 µM.


2020 ◽  
Vol 76 (11) ◽  
pp. 1005-1009
Author(s):  
Mehdi Khalaj ◽  
Abolfazl Olyaei ◽  
Mahdieh Sadeghpour ◽  
Arash Lalegani ◽  
Janusz Lipkowski ◽  
...  

A novel complex has been prepared using the (E)-4-nitro-N-(pyridin-2-ylmethylidene)aniline bidentate Schiff base ligand and PtCl2, namely, dichlorido[(E)-4-nitro-N-(pyridin-2-ylmethylidene)aniline-κ2 N,N′]platinum(II) acetonitrile hemisolvate, [PtCl2(C12H9N3O2)]·0.5CH3CN, 1. According to the X-ray measurements of the crystal structure, the PtII ion adopts a PtCl2N2 square-planar coordination. The coordination of the Schiff base ligand to the PtII ion occurs in a cyclic bidentate fashion, as a result of which a five-membered metallacycle is formed. Furthermore, in the structure of 1, the neutral molecules form a one-dimensional chain structure through C—H...Cl and C—H...O hydrogen bonds. The characterization of the complex was performed via single-crystal X-ray diffraction, IR spectroscopy and elemental analysis, and the antioxidant activity of the complex was evaluated using spectrophotometry by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method.


2014 ◽  
Vol 79 (5) ◽  
pp. 545-556
Author(s):  
Marija Mirkovic ◽  
Nadezda Nikolic ◽  
Dusan Mijin ◽  
Milka Avramov-Ivic ◽  
Agnes Kapor ◽  
...  

The diimine-dioxime ligand, 4,9-diaza-3,10-diethyl-3,9-dodecadiene-2,11-dione bisoxime (LH2), containing a N4 donor set was prepared by Schiff base condensation of 2-hydroxyimino-3-pentanone and 1,4-diaminobutane in two ways: in protic and in aprotic solvent. Higher yield of (LH2) imine was obtained when the synthesis was carried out using protic solvent (C2H5OH) instead of aprotic benzene (78% and 30%, respectively). Cu(II) metal complex of diimine-dioxime was synthesized in CH3OH from metal salt and LH2 in mole ratio 1:1. The isolated complex was characterized by the elemental analysis, IR spectroscopy and cyclic voltammetry. The structure of [Cu2(LH)2]?(ClO4)2 was determined by the single-crystal X-ray diffraction analysis. Comparison with the structurally related diimine-dioxime Cu(II) complexes revealed the influence of the weak Cu???O(perchlorate) interaction on the geometry of the metallocycle.


1997 ◽  
Vol 62 (10) ◽  
pp. 1623-1630 ◽  
Author(s):  
Radek Marek ◽  
Jaromír Marek ◽  
Jiří Dostál ◽  
Jiří Slavík

(-)-Armepavine, a benzylisoquinoline alkaloid isolated from Papaver caucasicum, was examined by gradient-enhanced 2D NMR spectroscopy and X-ray diffraction analysis. Unambiguous 1H, 13C, and 15N NMR assignment of the title alkaloid is reported.


2013 ◽  
Vol 448-453 ◽  
pp. 2925-2928
Author(s):  
Yan Lin ◽  
Han Feng Cui ◽  
Hao Fan

s: A novel Schiff-base compound based on ferrocene I has been synthesized and characterized by X-ray diffraction. Electrochemical measurements exhibit that this new ferrocenyl schiffbase undergoes a reversible one-electron redox process.


1989 ◽  
Vol 44 (3) ◽  
pp. 307-311 ◽  
Author(s):  
Yuzo Nishida ◽  
Miyuki Masumoto ◽  
Yutaka Mori

The crystal structure of the binuclear copper(II) complex. [Cu2(L)(2-pyridonato)] was determined by X-ray diffraction, where H3(L) represents the Schiff base ligand derived from 1,3-diaminopropane-2-ol and acetylacetone. Two copper(II) ions are bridged by alkoxide and 2-pyridonate groups with a Cu-Cu separation of 3.249(2) Å . Ferromagnetic interaction is found to be operating in this complex, which is attributed to the small dihedral angle (121°) between the two planes containing the copper(II) ion.


Synlett ◽  
2017 ◽  
Vol 28 (17) ◽  
pp. 2247-2252 ◽  
Author(s):  
Norah Bennamane ◽  
Oualid Talhi ◽  
Artur Silva ◽  
Brahim Cherfaoui ◽  
Houria Lakhdari ◽  
...  

The synthesis of 2,3,4,5,10,11-hexahydro-1H-dibenzo[b,e][1,4]diazepin-1-ones was revisited and a catalyst-free method was established, by exploring the reactivity of 3-[(2-aminoaryl)amino]dimedones towards carbonylated electrophiles. 2D NMR and single-crystal X-ray diffraction studies were used to characterize the structures unequivocally and to review the mechanism leading to the formation of supposed positional isomers. The action of 3-[(2-aminoaryl)amino]dimedones on chromene-3-carboxylic acid, fumaryl, and oxalyl chloride has led to dibenzo[b,e][1,4]diazepin-1-one ring opening to produce novel Z-configured enaminone and linear diamides.


RSC Advances ◽  
2019 ◽  
Vol 9 (71) ◽  
pp. 41737-41744 ◽  
Author(s):  
Yaning Guo ◽  
Xiaobing Hu ◽  
Xinli Zhang ◽  
Xiaohua Pu ◽  
Yue Wang

Reaction of a symmetric compartmental Schiff base ligand (HL) with copper(ii) salt in 2 : 1 M ratio in methanol gave rise to a mononuclear copper(ii) complex, which was characterized by single crystal X-ray diffraction studies.


Sign in / Sign up

Export Citation Format

Share Document