Direct Formation of 2-Substituted 2H-Indazoles by a Pd-Catalyzed Reaction between 2-Halobenzyl Halides and Arylhydrazines.

A direct and operationally simple method for the regioselective synthesis of 2-aryl-substituted 2H-indazoles is reported. The Pd-catalyzed reaction between easily available 2-bromobenzyl bromides and arylhydrazines employing Cs2CO3 as the base and t-Bu3PHBF4 as the ligand in DMSO at 120 °C in a sealed tube delivers the 2-substituted-2H-indazoles in a single synthetic step with yields up to 79%. The new method is based on a regioselective intermolecular N-benzylation followed by intramolecular N-arylation and oxidation.

A new acetylacetone derivative inhibits breast cancer by apoptosis induction and angiogenesis inhibition.

AIM: Cancer is one of the main causes of death worldwide. High mortality rates were reported among breast cancer patients which makes the development of new anticancer agents targeting breast cancer a priority. The synthesis of the compounds incorporating- N=N- group is an important field of research that may lead to the discovery of new anticancer drug. MATERIALS AND METHODS: In this work, we report the synthesis of a compound has O and N centers with the incorporation of the arylazo group (4-BrC6H4-N=N-) into acetylacetone to synthesize 3-(4-Bromo phenylazo)-2,4-pentanedione. Physical characteristics of the newly synthesized compound were determined by measuring electronic absorption spectra, nuclear magnetic resonances, and the infrared absorption spectrum. The inhibitory effect of the compound against breast cancer cell lines was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Its effect on angiogenesis was evaluated by measuring vascular endothelial growth factor (VEGF) levels in treated cells. The ability of the compound to induce apoptosis in cancer cells was tested by measuring caspase-3 activity, and its capacity to stimulate the immune system was evaluated by measuring the levels of interferon gamma (IFN-γ), interleukin-2 (IL-2), IL-4, and IL-10 cytokines in treated lymphocytes. RESULTS: Significant antiproliferative activity against breast cancer cell lines was observed in treated cells. Low levels of VEGF and high caspase-3 activity were observed in treated cells. Levels of IFN-γ, IL-2, and IL-4 were increased after treating lymphocytes with this compound. CONCLUSION: 3-(4-Bromo phenylazo)-2,4-pentanedione is a promising anticancer agent that can inhibit breast cancer cells through apoptosis induction and angiogenesis inhibition. Further testing is needed to clearly determine the molecular mechanisms of the anticancer effect of this compound.

Variable noninnocence of substituted azobis(phenylcyanamido)diruthenium complexes.

The synthetic chemistry of substituted 4,4'-azobis(phenylcyanamide) ligands was investigated, and the complexes [{Ru(tpy)(bpy)}2(µ-L)][PF6]2, where L = 2,2':5,5'-tetramethyl-4,4'-azobis(phenylcyanamido) (Me4adpc(2-)), 2,2'-dimethyl-4,4'-azobis(phenylcyanamido) (Me2adpc(2-)), unsubstituted (adpc(2-)), 3,3'-dichloro-4,4'-azobis(phenylcyanamido) (Cl2adpc(2-)), and 2,2':5,5'-tetrachloro-4,4'-azobis(phenylcyanamido) (Cl4adpc(2-)), were prepared and characterized by cyclic voltammetry and vis-near-IR (NIR) and IR spectroelectrochemistry. The room temperature electron paramagnetic resonance spectrum of [{Ru(tpy)(bpy)}2(µ-Me4adpc)](3+) showed an organic radical signal and is consistent with an oxidation-state description [Ru(II), Me4adpc(•-), Ru(II)](3+), while that of [{Ru(tpy)(bpy)}2(µ-Cl2adpc)](3+) at 10 K showed a low-symmetry Ru(III) signal, which is consistent with the description [Ru(III), Cl2adpc(2-), Ru(II)](3+). IR spectroelectrochemistry data suggest that [{Ru(tpy)(bpy)}2(µ-adpc)](3+) is delocalized and [{Ru(tpy)(bpy)}2(µ-Cl2adpc)](3+) and [{Ru(tpy)(bpy)}2(µ-Cl4adpc)](3+) are valence-trapped mixed-valence systems. A NIR absorption band that is unique to all [{Ru(tpy)(bpy)}2(µ-L)](3+) complexes is observed; however, its energy and intensity vary depending on the nature of the bridging ligand and, hence, the complexes' oxidation-state description.

Ruthenium(II) bipyridine complexes bearing new keto-enol azoimine ligands: synthesis, structure, electrochemistry and DFT calculations.

The novel azoimine ligand, Ph-NH-N=C(COCH3)-NHPh(C≡CH) (H2L), was synthesized and its molecular structure was determined by X-ray crystallography. Catalytic hydration of the terminal acetylene of H2L in the presence of RuCl3·3H2O in ethanol at reflux temperature yielded a ketone (L1=Ph-N=N-C(COCH3)=N-Ph(COCH3) and an enol (L2=Ph-N=N-C(COCH3)=N-PhC(OH)=CH2) by Markovnikov addition of water. Two mixed-ligand ruthenium complexes having general formula, trans-[Ru(bpy)(Y)Cl2] (1-2) (where Y=L1 (1) and Y=L2 (2), bpy is 2.2'-bipyrdine) were achieved by the stepwise addition of equimolar amounts of (H2L) and bpy ligands to RuCl3·3H2O in absolute ethanol. Theses complexes were characterized by elemental analyses and spectroscopic (IR, UV-Vis, and NMR (1D (1)H NMR, (13)C NMR, (DEPT-135), (DEPT-90), 2D (1)H-(1)H and (13)C-(1)H correlation (HMQC) spectroscopy)). The two complexes exhibit a quasi-reversible one electron Ru(II)/Ru(III) oxidation couple at 604 mV vs. ferrocene/ferrocenium (Cp2Fe(0/+)) couple along with one electron ligand reduction at -1010 mV. The crystal structure of complex 1 showed that the bidentate ligand L1 coordinates to Ru(II) by the azo- and imine-nitrogen donor atoms. The complex adopts a distorted trans octahedral coordination geometry of chloride ligands. The electronic spectra of 1 and 1+ in dichloromethane have been modeled by time-dependent density functional theory (TD-DFT).

Design, synthesis, characterization of novel ruthenium(II) catalysts: highly efficient and selective hydrogenation of cinnamaldehyde to (E)-3-phenylprop-2-en-1-ol.

In this contribution, two novel supported and non-supported ruthenium(II) complexes of type [RuCl2(dppme)(NN)] where [dppme is H2C=C(CH2PPh2)2 and NN is N1-(3-(trimethoxysilyl)propyl)ethane-1,2-diamine] were prepared. The NN co-ligand caused release of one of the dppme ligands from [RuCl2(dppme)2] precursor to yield complex 1. The process of substitution of dppme by NN was monitored by 31P{1H}-NMR. Taking advantage of the presence of trimethoxysilane group in the backbone of complex 1, polysiloxane xerogel counterpart, X1, was prepared via sol-gel immobilization using tetraethoxysilane as cross-linker. Both complexes 1 and X1 have been characterized via elemental analysis, CV and a number of spectroscopic techniques including FT-IR, 1H-, 13C-, and 31P-NMR, and mass spectrometry. Importantly, carbonyl selective hydrogenation was successfully accomplished under mild conditions using complex 1 as a homogenous catalyst and X1 as a heterogeneous catalyst, respectively.

Characterization and biological activities of two copper(II) complexes with dipropylenetriamine and diamine as ligands.

Two new mixed-ligand copper(II) complexes, [Cu(dipn)(NN)]Br2(1-2) [dipn=dipropylenetriamine, NN=ethylenediamine (en) (1) and propylenediamine (pn) (2)], have been synthesized. These complexes were characterized by spectroscopic and thermal techniques. Crystal structure for 2 shows a distorted trigonal-bipyramidal geometry around Cu(II) ion with one solvate water molecule. Antimicrobial and antiproliferative assays were conducted to evaluate the biological activities of these complexes. The complexes exhibit a promising antimicrobial effect against an array of microbes at 200µg/mL concentration. The antiproliferative assay shows a high potential of these complexes to target Human keratinocyte cell line with IC50 values of 155 and 152µM. The absorption spectrum of 2 in water was modeled by time-dependent density functional theory (TD-DFT).

Observation on symmetry properties of sodium zinc(II)-2,9,16,23-phthalocyanine tetracarboxylate in water:NaOH solution.

The shift of the Q-band of sodium zinc(II)-2,9,16,23-phthalocyanine tetracarboxylate (ZnPc(COONa)4) to about 800 nm is attributed to the influence of the electron-donating property of the carboxylate groups substituted in the ß-position. ZnPc(COONa)4 which was found to have a symmetry of D 2h characterized by a splitting of the Q transition. This splitting was interpreted by the formation of dianionic symmetric ZnPc(COONa)4 resulting from the dissociation of the pyrrole protons as well as the possibility of Na(+) dissolution of ZnPc(COONa)4 in the aqueous solution of NaOH.

Ruthenium(II) bipyridine complexes bearing quinoline-azoimine (NN'N″) tridentate ligands: synthesis, spectral characterization, electrochemical properties and single-crystal X-ray structure analysis.

Four octahedral ruthenium(II) azoimine-quinoline complexes having the general molecular formula [Ru(II)(L-Y)(bpy)Cl](PF6) {L-Y=YC6H4N=NC(COCH3)=NC9H6N, Y=H (1), CH3 (2), Br (3), NO2 (4) and bpy=2,2'-bipyrdine} were synthesized. The azoimine-quinoline based ligands behave as NN'N″ tridentate donors and coordinated to ruthenium via azo-N', imine-N' and quinolone-N″ nitrogen atoms. The composition of the complexes has been established by elemental analysis, spectral methods (FT-IR, electronic, (1)H NMR, UV/Vis and electrochemical (cyclic voltammetry) techniques. The crystal structure of complex 1 is reported. The Ru(II) oxidation state is greatly stabilized by the novel tridentate ligands, showing Ru(III/II) couples ranging from 0.93-1.27 V vs. Cp2Fe/Cp2Fe(+). The absorption spectrum of 1 in dichloromethane was modeled by time-dependent density functional theory (TD-DFT).

DNA Binding Test, X-Ray Crystal Structure, Spectral Studies, TG-DTA, and Electrochemistry of [CoX 2 (dmdphphen)] (Dmdphphen Is 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline, X = Cl, and NCS) Complexes.

Two new neutral mixed-ligand cobalt(II) complexes, [CoCl2(dmdphphen)] 1 and [Co(NCS)2(dmdphphen)] 2, where dmdphphen is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, were synthesized and characterized by an elemental analysis, UV-Vis, IR, TG/DTA, cyclic voltammetry CV, and single X-ray diffraction. Complex 2 crystallized as monoclinic with a space group P21/c. Co(II) ions are located in a distorted tetrahedral environment. TG/DTA result shows that these complexes are very stable and decomposed through one-step reaction. The two complexes exhibit a quasireversible one-electron response at -550 and 580 mV versus Cp2Fe/Cp2Fe(+), which has been assigned to Co(I)/Co(II) and Co(II)/Co(III) couples. Absorption spectral studies reveal that such complexes exhibit hypochromicity during their interaction with CT-DNA.

Trans/cis isomerization of [RuCl2{H2C=C(CH2PPh2)2)}(diamine)] complexes: synthesis, spectral, crystal structure and DFT calculations and catalytic activity in the hydrogenation of α,ß-unsaturated ketones.

Three complexes of the general formula trans/cis-[Ru((II))(dppme)(N-N)Cl2] {dppme is H2C=C(CH2PPh2)2 and N-N is 1,2-diaminocyclohexane (trans/cis-(1)) and 1-methyl-1,2-diaminopropane (trans-(2)} were obtained by reacting trans-[RuCl2(dppme)2] with an excess amount of corresponding diamine in CH2Cl2 as a solvent. The complexes were characterized by an elemental analysis, IR, (1)H, (13)C and (31)P{1H} NMR, FAB-MS and UV-visible. The trans-(1) (kinetic product) readily isomerizes to the cis-(1) (thermodynamic product) and this process was followed by using (31)P{(1)H} NMR, cyclic voltammetry and UV-vis spectroscopy. The electrochemical studies on complex (1) reveal that the Ru(III)/Ru(II) couples are sensitive to the isomer (trans/cis) formed. The cis-(1) was confirmed by X-ray structure and (31)P{(1)H} NMR. Transfer-hydrogenation reactions for reduction of trans-4-phenyl-3-butene-2-one were conducted using complexes trans/cis-(1) and trans-(2). The electronic spectra of cis/trans-(1) in dichloromethane were calculated with the use of time-dependent DFT methods.

Heterotrimetallic Ru(II)/Pd(II)/Ru(II) complexes: synthesis, crystalstructure, spectral characterization, DFT calculation and antimicrobial study.

New ruthenium(II) mononuclear complexes of the type [RuCl2(PPh3)2(η(2)-triamine)] (2) [RuCl(PPh3)2(η(3)-triamine)]Cl (5) (triemine=N(1)-(2-aminoethyl)-1,2-ethanediamine) have been synthesized by reacting [RuCl2(PPh3)3] (1) with one mole equivalent of N(1)-(2-aminoethyl)-1,2-ethanediamine in dichloromethane. Reaction of (2) with half-equivalent of (PhCN)2PdCl2 or Pd(OAc)2 in dichloromethane as a solvent afforded two novel heterotrimetallic Ru(II)-Pd(II)-Ru(II) complexes, [Ru(II)Cl2(PPh3)2(triamine)]2[Pd(II)X2](X=Cl, OAc) (3 and 4), bearing bioactive ligand. The progress of the undertaken reactions was monitored by (31)P{1H} NMR and FTIR. Crystal structure of complex 2 was confirmed by X-ray diffraction. The absorption spectrum of 2 in dichloromethane was modeled by time-dependent density functional theory (TD-DFT). The in vitro antimicrobial studies of complex 2-5 against an array of microorganisms (bacteria and fungi) were conducted. Complexes 3 and 4 exhibit high dual antibacterial and antifungal activity inhibiting microorganisms possibly via hydrolytic pathway which further evidenced by electrochemical analyses. The complexes 3 and 4 show a high inhibitory activity at 200 µg/ml concentration, suggesting that complexes 3 and 4 are two efficient catalytic inhibitor of microorganisms and further, they should be tested against cancer strains.

One step synthesis of NiO nanoparticles via solid-state thermal decomposition at low-temperature of novel aqua(2,9-dimethyl-1,10-phenanthroline)NiCl2 complex.

[NiCl2(C14H12N2)(H2O)] complex has been synthesized from nickel chloride hexahydrate (NiCl2·6H2O) and 2,9-dimethyl-1,10-phenanthroline (dmphen) as N,N-bidentate ligand. The synthesized complex was characterized by elemental analysis, infrared (IR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy and differential thermal/thermogravimetric analysis (TG/DTA). The complex was further confirmed by single crystal X-ray diffraction (XRD) as triclinic with space group P-1. The desired complex, subjected to thermal decomposition at low temperature of 400 °C in an open atmosphere, revealed a novel and facile synthesis of pure NiO nanoparticles with uniform spherical particle; the structure of the NiO nanoparticles product was elucidated on the basis of Fourier transform infrared (FT-IR), UV-vis spectroscopy, TG/DTA, XRD, scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDXS) and transmission electron microscopy (TEM).

rac-(E,E)-N,N'-Bis(2-chloro-benzyl-idene)cyclo-hexane-1,2-di-amine.

In the title racemic Schiff base ligand, C20H20Cl2N2, which was prepared by the condensation of 2-chloro-benzaldehyde and cyclo-hexane-1,2-di-amine, the cyclo-hexane ring adopts a chair conformation and the dihedral angle between the aromatic rings of the 2-chloro-phenyl substituent groups is 62.52 (8)°. In the structure, there are two short intra-molecular methine C-H⋯Cl inter-actions [C⋯Cl = 3.066 (2) and 3.076 (3) Å], and in the crystal there are also weak inter-molecular aromatic C-H⋯Cl [3.464 (3), 3.553 (3) and 3.600 (3) Å] and Cl⋯Cl [3.557 (3) and 3.891 (3) Å] contacts.

2-Phen-oxy-ethyl benzoate.

In the title compound, C15H14O3, the dihedral angle between the benzene rings is 75.85 (7)°. In the crystal, centrosymmetrically related mol-ecules are weakly associated through pairs of inter-actions between a benzene ring and an O atom of the ester group [ring centroid⋯O = 3.952 (7) Å], and through pairs of inter-actions between the other benzene ring and an O atom of the phen-oxy group [ring centroid⋯O = 3.912 (7) Å], giving chains extending along [110].

Dichlorido(2,9-dimethyl-1,10-phenanthroline-κ(2)N,N')mercury(II).

The title compound, [HgCl(2)(C(14)H(12)N(2))], consists of one 2,9-dimethyl-1,10-phenanthroline (dmphen) ligand chelating the Hg(II) ion and two chloride ligands coordinating to the Hg(II) ion, forming a distorted tetra-hedral environment. The dmphen ligand is nearly planar (r.m.s. deviation = 0.0225 Å). The dihedral angle between the normal to the plane defined by the Hg(II) atom and the two Cl atoms and the normal to the plane of the dmphen ring is 81.8 (1)°.

N'-[(E)-2-Chloro-benzyl-idene]thio-phene-2-carbohydrazide.

There are two independent mol-ecules in the asymmetric unit of the title compound, C12H9ClN2OS, a Schiff base derived from hydrazide, in which the dihedral angles between the thio-phene and benzene rings are 3.6 (3) and 7.3 (3)°. In the crystal, the two independent mol-ecules are arranged about an approximate non-crystallographic inversion center and are connected by two N-H⋯O hydrogen bonds. Weak C-H⋯Cl contacts are also present. Conversely, there are neither significant aromatic stacking inter-actions nor contacts involving S atoms.

3,6-Diacetyl-1,4-diphenyl-1,4-dihydro-1,2,4,5-tetra-zine.

In the title compound, C(18)H(16)N(4)O(2), the central six-membered ring has a boat conformation.

Outer sphere perturbation of delocalized mixed-valence complexes.

The complexes [[Ru(ttp)(bpy)](2)(micro-adpc)][PF(6)](2) and [[Ru(ttp)(bpy)](2)(micro-dicyd)][PF(6)](2), where ttp is 4-toluene-2,2':6',2' '-terpyridine, bpy is 2,2'-bipyridine, adpc(2)(-) is azodi(phenylcyanamide), and dicyd(2)(-) is 1,4-dicyanamidebenzene, were prepared and characterized by IR and NIR, vis spectroelectrochemistry, and cyclic voltammetry. The crystal structure of the complex, [[Ru(ttp)(bpy)](2)(micro-adpc)][PF(6)](2).6DMF, revealed a planar bridging adpc(2)(-) ligand with the cyanamide groups adopting an anti configuration. IR and comproportionation data are consistent with delocalized mixed-valence complexes, and a spectroscopic analysis assuming C(2)(h) microsymmetry leads to a prediction of multiple MMCT transitions with the lowest energy transition equal to the resonance exchange integral for the mixing of ruthenium donor and acceptor orbitals with a bridging ligand orbital (the preferred superexchange pathway). The solvent dependence of the MMCT band energy that is seen for [[Ru(ttp)(bpy)](2)(micro-adpc)](3+) is due to a ground state weakening of metal-metal coupling because of solvent donor interactions with the acceptor azo group of the bridging ligand.