Synthesis and Physico-Chemical Characterizations of Novel Hydrazone Ligands and Their Metal Complexes against Hormone-Dependent and Independent Cancers

This work deals with the synthesis and physicochemical characterizations of a new group of novel retinoidal ligands and their metal complexes. Their in vitro anti-proliferative activities have shown that ligand L1 is effective against human breast cancer BT-20 and MCF-7 cell lines. At the same time, compound L2 exerts its effect on human prostate cancer PC-3 and human breast cancer MDA-MB-231 and MCF-7 cell lines respectively. The retinoid ligands exert their pleiotropic action toward retinoic acid receptors (RARs) than their metal complexes but all compounds exhibit concentration-dependent.

Synthesis and Crystal Structure of Lanthanum Nitrate with Methyl-2-pyridyl Ketone Benzoyl Hydrazone

A novel La complex with methyl-2-pyridyl ketone benzoyl hydrazone has been synthesized and determined by single crystal X-ray diffraction. The crystal is monoclinic with space group C2/c, a =1 7081(3) nm, b =1 5660(3) nm, c =1 3512(3) nm, α=90 00°, β=94 39(1)°, γ=90 00°, V =3 6037(12) nm 3, Z =4 . The complex is a ten-coordinated one with a lanthanum ion surrounded by a N 4O 6 set. The crystal structure is stabilized by hydrogen bonds between water molecules and NO - 3 anions.

Synthesis, Crystal Structure, and Biological Activity of 4-Chlorobenzaldehyde (2-trifluoromethylTrifluoromethyl-5,6,7,8-tetrahydrobenzo[4 ,5]-thieno[2,3-d]pyrimidin-4-yl)hydrazone Monohydrate

The novel title compound 4-chlorobenzaldehyde （2-trifluoromethyl-5,6,7,8- tetrahydro- benzo[4,5]thieno[2,3-d]pyrimidin-4-yl）hydrazone monohydrate （C18H14C1F3N4S.H20, Mr = 428.86） has been synthesized by a condensation reaction of 4-chlorobenzaldehyde with （2-trifuoromethyl-5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4-yl）hydrazine, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 7.4252（7）, b = 26.344（2）, c = 10.3095（9） A, /3 = 109.407（2）~, V= 1902.0（3） A3, Z = 4, Dc = 1.498 g/cm^3, p = 0.356 mm-1, F（000） = 880, the final R = 0.0564 and wR = 0.1681 for 2343 observed reflections with I 〉 2o（/）. X-ray diffraction analysis reveals that the title hydrazone molecule is nearly planar except for the cyclohexene and trifluoromethyl moieties. In the crystal packing, the molecules form stacks by a three-dimensional framework, which results from intermolecular N（3）-H（3）...O（1）, O（1）-H（1B）...N（2）, O（1）- H（1B）...N（4） and O（1）-H（1A）...F（1） hydrogen bonds via water molecules together with π-π stacking interactions. Molecular geometry of the title compound in the ground state optimized by B3LYP functional with 6-311G＊＊ basis sets indicates that the calculations are in agreement with the experimental data. The preliminary bioassay suggested that the title compound exhibits relatively good fungicidal activity against Fusarium oxysporium fsp.vasinfectum and Dothiorella gregaria.

Synthesis and Crystal Structure of a Vanadium(V) Complex with 2-Hydroxy-1-naphthaldehyde Isonicotinoyl Hydrazone

The mononuclear vanadium（V） complex with 2-hydroxyl-l-naphthaldehyde isonicotinoyl hydrazone was synthesized and characterized by single-crystal X-ray diffraction. The crystal is of monocfinic, space group P2 1/n with α = 10.3153（15）, b = 7.4024（11 ）, c = 24.413（4） A, β = 101.911（2）°, V= 1824.0（5） A^3, Z= 4, Mr = 427.28, Dc = 1.556 g/cm^3, F（000） = 880,μ（MoKα） = 0.591, the final R = 0.0372 and wR = 0.0926. The vanadium（V） atom adopts a distorted square-pyramidal geometry coordinated by the tridentate ligand and two oxygen atoms. The hydrogen bonds and strong π-π stacking interactions link the complex molecules into a 3-D network structure.

Synthesis, Crystal Structure and Antibacterial Activity of Two Hydrazones Derived from 2-Fluorobenzhydrazide

Two new Schiff base benzoyl hydrazone compounds, C14H10FN3O3 （Ⅰ） and C14H10F2N2O （Ⅱ）, have been synthesized and characterized by elemental analysis, IR, UV and X-ray single-crystal diffraction. Both compounds crystallize in monoclinic, space group P21/c with a = 7.0514（14）, b = 25.928（5）, c = 7.7099（15）, β = 111.823（2）°, V = 1308.6（4）3, Z = 4, C14H10FN3O3, Mr = 287.25, Dc = 1.458 g/cm3, μ（MoKα） = 0.115 mm-1, F（000） = 592, the final R = 0.0841 and wR = 0.2489 for 1901 observed reflections （I 2σ（I）） for I; a = 11.232（3）, b =12.735（4）, c = 8.612（2） , β = 90.869（3）°, V = 1231.7（6）3, Z = 4, C14H10F2N2O, Mr = 260.24, Dc = 1.403 g/cm3, μ（MoKα） = 0.111 mm-1, F（000） = 536, the final R = 0.0453 and wR = 0.1085 for 1317 observed reflections （I 2σ（I）） for Ⅱ. The antibacterial activities of both compounds against two bacteria were first studied and one compound showed considerable antibacterial activity against K. Pneumonia and S. aureus.

Studies on Lead(Ⅱ) Complexes of Ferrocenylaldehyde Aroylhydrazones

The complexes of four ferrocenylaldehyde aroylhydrazones with lead(Ⅱ) were synthesized and characterized. Their compositions, bonding forms and properties were researched by means of elemental analysis, IR, UV Vis, 1H NMR spectra, thermal analysis and molar conductance. The free ligands which existed in the keto form coordinated to lead(Ⅱ) in the enol form to form neutral complexes. The molar ratio of the ligand to lead(Ⅱ) is 2∶1 and the thermal stability of the complex is higher than that of the corresponding ligand because of the formation of the stable chelate ring. The ligands and the complexes are all non electrolytes.

Simple, Selective, and Sensitive Spectrophotometric Method for Determination of Trace Amounts of Nickel(Ⅱ), Copper (Ⅱ), Cobalt (Ⅱ), and Iron (Ⅲ) with a Novel Reagent 2-Pyridine Carboxaldehyde Isonicotinyl Hydrazone

A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone（2-PYAINH） was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1：2 yellow-orange, 1：2 yellow-green, 1：2 yellow and 1：1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer＇s law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell＇s sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.

Synthesis, Characterization and Antibacterial Activity of Biologically Important Vanillin Related Hydrazone Derivatives

Hydrazone derivatives of vanillin are found to possess anti-bacterial activities. Based on higher bio-activity of hydrazones, new hydrazone derivatives were synthesized from Piperdine-4-carboxylicacid methyl ester (1). The compounds 1-pyrimidine-2-yl piperidine-4-carboxylicacid(4-hydroxy-3-methoxy benzylidine)-hy- drazide (10), 1-pyrimidine-2-yl piperidine-4-carboxylicacid (3,4-dimethoxy benzylidine) hydrazide (11), 1-pyrimidine-2-yl piperidine-4-carboxylicacid(4-butoxy-3-methoxy benzylidine)-hydrazide (12), 1-pyr- imidine-2-yl piperidine-4-carboxylicacid(3-methoxy-4(2-methoxy ethoxy) benzylidine)-hydrazide (13) were synthesized, purified and characterized by 1HNMR, 13CNMR, LCMS, FT-IR and HPLC techniques. The synthesized hydrazone derivatives were further checked for anti-bacterial activities by paper disc diffusion method against Pseudomonas aeruginosa and Staphylococcus aureus bacterial strains.

Syntheses, Crystal Structures and Antimicrobial Activities of Vanadium(V) Complexes with Similar Tridentate Hydrazone Ligands

Two hydrazone ligands （E）-N＇-（2-hydroxy-5-methoxybenzylidene）-2-hydroxybenzo- hydrazide （HLa） and （E）-N＇-（3,5-dichloro-2- hydroxybenzylidene）-4-methoxybenzohydrazide （HLb） were prepared and characterized by IR, UV-Vis and 1H NMR spectra. Based on the hydrazone ligands, two new structurally similar vanadium（V） complexes, [VOLaL].CH3OH （1） and [vOLbL] （2）, where L is the monoanionic form of benzohydroxamic acid （HL）, were prepared and characterized by IR and UV-Vis spectra, and single-crystal X-ray diffraction. Complex 1 crystallizes as the monoclinic space group P21/n, with a = 7.5208（10）, b = 15.490（2）, c = 20.8929（18） A, β = 96.373（2）°, V = 2418.9（5） A3, Z = 4, R = 0.0831, wR = 0.2607 and GOOF = 1.061. Complex 2 crystallizes as the monoclinic space group P21/c, with a = 11.8577（18）, b = 16.468（2）, c = 12.2288（18） A, β = 106.064（2）°, V= 2294.7（6） A3, Z = 4, R= 0.0741, wR= 0.1745 and GOOF= 1.014. X-ray analysis indicates that the complexes are mononuclear vanadium （V） species, with the V atoms located in the octahedral coordination. The hydrazone ligands and the complexes were evaluated for their antibacterial （Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Pseudomonas fluorescence） and antifungal （Candida albicans and Aspergillus niger） activities by MTT （3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrazolium bromide） method.

Synthesis and Crystal Structure of a New cis-Dioxovanadium (V) Complex with Pyruvic Acid Isonicotinyl Hydrazone (PAINH)

A new cis-dioxovanadium （V） complex [VO2（C9H8N3O3）]（C5H5N） involving a carboxyl group coordination employing a tridentate Schiff Base derived from pyruvic acid and isonicotinyl hydrazide is reported. This complex crystallizes in triclinic, space group P1^- with a = 7.3522 （12）, b = 7.8376（13）, c = 14.898（2） ,A°, a = 84.010（2）, β = 86.568（2）, γ= 64.586（2）°, V = 771.1（2）A °^3 ,Z = 2, F（000） = 376, Mr = 368.22, D, = 1.586 g/cm^3, g = 0.677 mm ^-1, R = 0.0421 and wR = 0.1253. The vanadium atom of the dioxovanadium （V） is five-coordinated to furnish a distorted trigonal bipyramid geometry.

Syntheses,Crystal Structures and Biological Activities of the 2-Oxo-butyric Acid Salicylacylhydrazone Dibenzyltin Complexes

2-Oxo-butyric acid salicylacylhydrazone dibenzyltin（IV） complexes 1 {[o-OHC6H4（O）C=N-N=C（Et）COO]（CH3OH）[（C6H5CH2）2Sn]}2 and 2 {[o-OH-C6H4（O）C=N-N=C（Et）-COO]（CH3OH）[（2,4-Cl2C6H3CH2）2Sn]}2 have been synthesized. The complexes were characterized by IR, 1H, 13C and 119Sn NMR spectra, elemental analysis and thermal stability analysis, and the crystal structures were determined by X-ray diffraction. The crystal of complex 1 belongs to triclinic system, space group P1 with a = 8.9121（6）, b = 10.3875（7）, c = 14.5658（10） ？, α = 89.534（5）, β = 86.790（5）, γ = 70.103（6）°, Z = 1, V = 1265.85（15） ？3, Dc = 1.488 Mg·m^（-3）, m（Mo Kα） = 1.047 mm-1, F（000） = 576, R = 0.0466 and w R = 0.1054. The crystal of complex 2 belongs to monoclinic system, space group P21/n, a = 12.7165（10）, b = 17.8466（14）, c = 12.8538（10） ？, β = 95.1310（10）°, Z = 2, V = 2905.4（4） ？~3, Dc = 1.612 Mg·m^（-3）, m（Mo Kα） = 1.286 mm-1, F（000） = 1408, R = 0.0369 and w R = 0.0958. In vitro antitumor activities of both complexes were evaluated by the 3-（4,5-dimethylthiazoly-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay against three human cancer cell lines（NCI-H460, HepG2, MCF7） and one human cell line（HL7702）. Two complexes exhibited strong antitumor activity, and then they were expected after further chemical optimization of candidate compounds as anti-cancer drugs. The interaction between complexes and calf thymus DNA were studied by EB fluorescent probe. The interactions of the two complexes with calf thymus DNA were intercalation.

Synthesis, Spectroscopic, Molecular Modeling and Anti-Fungal Studies of Some Divalent Metal Complexes of 4-Hydroxyacetophenone Isonicotinoyl Hydrazone

A novel ligand N-4-hydroxyacetophenone isonicotinoyl hydrazone and its manganese(II) and nickel(II) metal complexes have been synthesized. The synthesized Schiff base and its metal complexes have been characterized by physical state determination, melting point and solubility measurements in different solvents, infrared, proton nuclear magnetic resonance, mass spectrometric and powder X-ray spectroscopic techniques. The thermal properties of the prepared compounds were obtained from TG/DTG measurements. On the basis of the analytical techniques, the ligand was found to be bidentate in nature coordinating to the metal ions through the azomethine nitrogen and carbonyl oxygen atoms leading to distorted octahedral geometries of the metal complexes which were modeled using MM2 force field. The ligand and its metal(II) complexes were evaluated for antifungal activity against Aspergillus fumigatus, Aspergillus niger, Candida albicans and Rhizopus stolonifera. The antifungal evaluation results revealed an enhanced activity upon coordination of the ligand with the metal(II) ions. The activity of the metal complex to the tested fungal strains was in the order Ni(II) > Mn(II).

Synthesis, Characterization and Properties of Lanthanide Nitrate Complexes with Isonicotinoyl Hydrazone

Some light-lanthanide nitrate complexes were obtained by the reaction of lanthanide nitrate with isonicotinoyl hydrazone (HL = N,N'-diisonicotinoyl-2-hydroxy-5-methyl-isophthalaldehyde dihydrazone) in methanol. The general formula of the complexes is Ln(L) (NO3)(2) . nH(2)O(Ln = La, Ce, Pr, Nd and Sm; n = 0, 1). The complexes were characterized by elemental analyses, conductance, thermal analyses, UV and IR spectra. The results show that the lanthanide ion in each complex is coordinated by oxygen and nitrogen atoms of the ligand (L) and the oxygen atoms of the nitrate. The amide-oxygen atoms of L coordinate to the Ln ions in its keto-form. The magnetic susceptibility of the neodymium complex shows that the magnetic data obey Curie-Weiss law in the range of 75K < T < 300K.

Synthesis and Crystal Structure of Binuclear Ytterbium Complex with Isonicotinoyl Hydrazone

The ytterbium complex of isonicotinoyl hydrazone was synthesized and the structure was determined by X-ray diffraction analysis. The crystal and molecular structure of the title complex [Yb-2(L)(3)](OH)(3) shows that the complex has two identical nine-coordinated ytterbium ions with each surrounded by N3O6 donor set, Two ytterbium ions are bridged by three phenolate oxygen atoms, The geometry around each ytterbium ions can be considered as a three-capped trigonal prism.

Synthesis and Complexation Properties of Novel Chiral Calix[4]-1,3-aza-crown and Calix[4]arene Hydrazone Derivative

Refluxing calix[4]-1,3-substituted benzaldehyde derivative（4） with glycine hydrazide derivative, we obtained a novel calix[4]arene hydrazone derivative（5） via ＂1＋2＂ condensation in a yield of 78%. In the reaction of compound 4 with L-leucine hydrazide derivative at room temperature, lariat calix[4]-1,3-aza-crown（6） with chiral amino acid group as branched chain was synthesized via ＂1＋ 1＂ addition in a yield of 70%. The preliminary extraction experiments suggested that hosting compounds 5 and 6 possessed good complexation abilities for a-amino acids.

Synthesis, Characterization and Antioxidative Activity of Lanthanide Complexes with 3,5-Dibenzyloxybenzoyl-2,4-Dihydroxybenzaldehyde-Hydrazone

In order to study the coordination character of the rare earth elements with hydrazones and the antioxidative activity of the ligand and the complexes, 3,5 dibenzyloxybenzoyl 2,4 dihydroxybenzaldehyde hydrazone (H 2L), a new chelating ligand, and its six lanthanide complexes, Ln (HL)(OAc) 2· n H 2O [Ln=La, Sm, Eu, Gd, Tb, Dy; n =2, 4, 5], were synthesized and characterized on the basis of elemental analyses, IR and 1H NMR spectra, molar conductivity. The results show that the lanthanide ions are coordinated by O, O and N donors of the phenol (Ar OH) without deprotonation, the enol oxygen of the hydrazone group (NCO -) and the azomethine group (CH=N) from the ligand respectively, and by the four carboxylic oxygen from two acetate groups (CH 3COO -) in the bidentate form. The scavenging activity of the ligand and the six lanthanides complexes on the 2,2 Diphenyl 1 picrylhydrazyl (DPPH) free radicals is also evaluated. The results show that both the ligand and the complexes have the scavenging activity on the DPPH radicals, and the scavenging activity of the complexes is better than the ligand.

Photo-isomerization of Aromatic α-Hydroxy Hydrazone

Photo-isomerization of aromatic α-hydroxy hydrazone was reported. We investigated the structures of salicylaldehyde phenylhydrozone（SP） in the ground state using density functional theory（DFT） with the B3LYP functional and the 6-311＋G（d） basis set. All nine possible isomers of SP in the ground state consist of seven phenol forms and two ketone forms. Intrisic reaction coordinate（IRC） analysis discloses the existence of a cycle driven by the two proton transfer processes in the ground and excited states of SP, which suggests that no ketonic form could exist in the ground state. Further theoretical studies of the potential energy surfaces support a trans-cis conversion followed by a relaxation to the stable form of SP in the excited states.

Synthesis and Characterization of Three Vanadium(Ⅴ) Complexes Incorporating Tridentate Hydrazone Ligands of Thiophene-2-carboxylic Hydrazide and 2-Furoic Acid Hydrazide

Divanadium（Ⅴ） complex [VO（aptch）（μ-OCH3）]2（1） and two monovanadium（Ⅴ） complexes [VO（apfah））（OEt）]（2a and 2b,H2aptch = 2-hydroxyacetophenone thiophene-2-car-boxylic hydrazone,H2apfah = 2-hydroxyacetophenone 2-furoic acid hydrazone） have been synthesized and characterized.Single-crystal X-ray diffraction studies reveal that 1 is a cen-trosymmetric dimer bridged by two methoxido O-atoms.Complex 1 crystallizes in the monoclinic crystal system,space groups P21/c with a = 7.4825（4）,b = 17.0928（11）,c = 11.6961（7） ,β = 98.172（4）o,Z = 2,F（000） = 728,μ = 0.829 mm-1,the final R = 0.0457 and wR = 0.1137 for 2654 observed reflections with I 〉 2（I）.The vanadium（V） is coordinated to the tridentate ligand,ethanol molecule to form a distorted square-pyramidal geometry,complexes 2a and 2b.Although 2a and 2b have the same asymmetric unit,they belong to different space groups.Complex 2a crystallizes in the monoclinic crystal system,space groups P21/n with a = 10.2293（2）,b = 15.6660（3）,c = 10.6298（2） ,β = 116.259（1）o,Z = 4,μ = 0.676 mm-1;complex 2b crystallizes in the triclinic crystal system,space groups P with a = 8.2808（4）,b = 9.4704（5）,c = 10.0819（5） ,α = 86.133（3）,= 81.956（3）,γ = 80.248（3）o,Z = 2 and μ = 0.670 mm-1.The hydrogen bonds are found to exist in 2b only.The crystal structure is stabilized by intermolecular hydrogen bonds of C-H···O.

Synthesis, Crystal Structure and Properties of a Novel Vanadium(Ⅴ) Oxoperoxo Complex Incorporating a Tridentate Hydrazone Ligand

A novel vanadium（V） oxoperoxo complex [VOO2（APTCH）（CH3OH）] （HAPTCH = 2-acetylpyridine thiophene-2-carboxylic hydrazone） has been synthesized and characterized by IR, TGA and X-ray single-crystal structure determination. The complex crystallizes in the monoclinic system, space group P21/c with a = 11.232（2）, b = 10.762（2）, c = 112.613（3）, β = 99.44（3）°, V = 1504.1（5）3, Dc = 1.657 g·cm-3, Z = 4, F（000） = 768, μ = 0.827 mm-1, the final R = 0.0392 and wR = 0.1073 for 2266 observed reflections with I 〉 2σ（I）. Single-crystal X-ray diffraction studies reveal that the vanadium（V） is coordinated by a tridentate ligand, methanol molecule and peroxo group to form a pentagonal-bipyramidal geometry. The crystal structure is stabilized by intermolecular hydrogen bonds of O-H···N and C-H···O.