Study of antidiabetic activity of two novel Schiff base derived dibromo and dichloro substituted compounds in streptozotocin-nicotinamide-induced diabetic rats: pilot study

Abstract Schiff bases are aldehyde-or ketone-like chemical compounds in which an imine or azomethine group replaces the carbonyl group. Such compounds show various beneficial biological activities, such as anti-inflammation and antioxidants. The present study addresses comprehensiveevaluation of antidiabetic effect of two novel dibromides and dichlorides substituted Schiff bases substituted Schiff bases (2,2'-[1,2-cyclohexanediylbis (nitriloethylidyne)]bis[4-chlorophenol] (CNCP) and 2, 2'-[1,2-cyclohexanediylbis(nitriloethylidyne)]bis[4-bromophenol] (CNBP) with two different doses, high (LD) and low (LD) in streptozotocin and nicotinamide induced diabetic rats. The rats were separated into normal, untreated, treated and reference groups. Except for the normal group, diabetes traits were induced in the rest animals. Insulin level was measured, and the effect of the compounds on biochemical parameters of liver function and lipid profile were evaluated. High glucose and decreased insulin level are observed in the groups. The histological evaluation confirms that the hepatic architecture in the treated animals with a low dose of CNCP is quite similar to that of the normal hepatic structure and characterized by normal central vein, hepatocytes without any fatty alterations and mild red blood cell infiltration. CNCP (LD) and CNBP (HD) are more successful in enhancing cell survival in the diabetic rat's liver and can be responsible for causing much healthier structure and notable morphology improvement.

Two novel Co(II) complexes with two different Schiff bases: inhibiting growth of human skin cancer cells

Using two flexible Schiff bases, H2L1 and H2L2, two new cobalt II (Co(II))-coordination compounds, namely, Py3CoL1 (1) and Py3CoL2 (2) (Py=pyridine, L1=3,5-ClC6H2(O)C=NC6H3(O)-4-NO2, L2=3,5-BrC6H2(O)C=NC6H3(O)-4-NO2) have been synthesized under solvothermal conditions. Single crystal X-ray structural analysis revealed that compounds 1 and 2 are both six-coordinate in a distorted octahedral geometry, and the 1D chain structure was formed by the π…π and C-H…O interactions or C-H…Cl interaction. The in vitro antitumor activities of 1, 2 and their corresponding organic ligands Py, L1, and L2 were studied and evaluated, in which three human skin cancer cell lines (A-431, HT-144 and SK-MEL-30) were used in the screening tests.

[Anticancer effects of some Girard-P reagent-based schiff bases and their Dimethyltin [IV] complexes on malignant glioblastoma cell line in in vitro culture]

Background: Glioblastoma [U-87] is the most common and most malignant of the glial tumors that appeared in the central nervous system. This is the first study that has evaluated the cytotoxic effects of various Girard-P reagent-based Schiff bases and their dimethyltin [IV] complexes on Glioblastoma cell line, U-87, viability

Materials and methods: In this experimental study, U-87 cell line was grown in DMEM supplemented with 10% FBS, penicillin/streptomycin [100 U/ml, 100 micro.g/ml] at 37 °C in 5% CO2, then the effects of different concentrations of complexes on Glioblastoma cell were evaluated by MTT and DAPI staining

Results: Herein, we demonstrated that these compounds had cytotoxicity effects of Glioblastoma cancer cells. In a dose dependent manner, a significant cytotoxicity was observed with increasing of PlMandP3

Conclusion: The results showed that Girard-P reagent-based Schiff bases and their dimethyltin [IV] complexes have the ability to induce cytotoxicity in the Glioblastoma cancer cell line in lower mg/ml concentrations. In conclusion, these findings may introduce a new view on the mode of action and possible application of new compounds in the cancer chemotherapy

Synthesis, pharmacological screening and computational analysis of some 2-[l-Indol-3-yl]-A [[un]substituted phenylmethylidene] acetohydrazides and 2-[l-Indol-3-yl]-7V[[un]substituted benzoyl/2-thienylcarbonyl] acetohydrazides

The undertaken research was initiated by transforming 2-[l-Indol-3-yl]acetic acid [1] in catalytic amount of sulfuric acid and ethanol to ethyl 2-[l-Indol-3-yl]acetate [2], which was then reacted with hydrazine monohydrate in methanol to form 2-[l-Indol-3-yl]acetohydrazide [3]. Further, The reaction scheme was designed into two pathways where, first pathway involved The reaction of 3 with substituted aromatic aldehydes [4a-o] in methanol with few drops of glacial acetic acid to generate 2-[l-Indol-3-yl]-AD-[[un]substitutedphenylmethylidene]acetohydrazides [5a-o] and in second pathway 3 was reacted with acyl halides [6a-e] in basic aqueous medium [pH 9-10] to afford 2-[l-Indol-3-yl]-AD-[[un]substitutedbenzoyl/2-thienylcarbonyl]acetohydrazides [7a-e]. All The synthesized derivatives were characterized by IR, EI-MS and !H-NMR spectral techniques and evaluated for their anti-bacterial potentials against Gram positive and Gram negative bacterial strains and it was found that compounds 7a-d exhibited antibacterial activities very close to standard Ciprofloxacin. The synthesized derivatives demonstrated moderate to weak anti-enzymatic potential against oc-Glucosidase and Butyrylcholinesterase [BChE] where, compounds 7c and 5c exhibited comparatively better inhibition against these enzymes respectively. Compounds 7a, 7d and 7e showed excellent anti-enzymatic potentials against Lipoxygenase [LOX] and their IC[5]o values were much lower than the reference standard Baicalein. Enzyme inhibitory activities were also supported by computational docking results. Compounds 5c, 7a, 7b and 7c also showed low values of % hemolytic activity as well, showing that these molecules were not toxic, indicating that these molecules can be utilized as potential therapeutic agents against inflammatory ailments

Antimicrobial salicylaldehyde schiff bases: synthesis, characterization and evaluation

As the pathogens soon develop resistance to the existing antibiotics, the demand for new and more effective anti-microbial agents is a continuous phenomenon. In this paper we are reporting synthesis and spectral data of eight Schiff bases of salicylaldehyde with different amines, and evaluation of their anti-microbial activities against different bacterial strains. The bases were synthesized by reflux method, and their structures were determined based FT-IR,[1]HNMR,[13]C-NMR and Mass spectrometric data. The Schiff bases synthesized included 2-[[[Z]-[2-hydroxyphenyl] methylidene] amino]benzoicacid [SB1], 4-[[[Z]-[2-hydroxyphenyl] methylidene] amino] benzoic acid [SB2],2- [[naphthalene-2-ylimino] methyl] phenol [SB3],2-2'-[benzene-1,4- iylbis [nitrilomethylylidene]] diphenol [SB4], 2-2'- [benzene-1,2-diylbis [nitrile-[E]-methylylidene]]diphenol [SB5], 2-[[2- phenylhydrazineylidene] methyl]phenol [SB6], 2- 2'-[ethene-1,2-diylbis[iminomethanediyl]]diphenol [SB7] and 2-[[Z]-[phenylimino] methyl]phenol [SB8]. The antimicrobial activities of synthesized Schiff bases were determined in terms of zones of inhibition and minimum inhibitory concentrations [MICs]. All the bases showed moderate to good activities against all the tested microorganisms. The MICs of most compounds were 100-200microg/mL against different microorganisms. However, it was 50micro g/mL for SB1 against P. aeruginosa [1], SB3 against P. aurantiaca, P. aeruginosa [1], E. coli [2], S. typhi [2] and C. freundii, SB4against E. coli [2], S. typhi [1] and S. maltophilia, SB5 against K. pneumoniae and S. typhi [2], SB6 against P. aeruginosa [3] and C. freundii, SB7 against E. cloacae and A. lipoferum, andSB8against E. coli [2]. Considerably active bases may prove to be potential candidates for future antibiotic drugs

A novel schiff base zinc coordination compound inhibits proliferation and induces apoptosis of human osteosarcoma cells / 华中科技大学学报（医学）（英德文版）

Various kinds of schiff base metal complexes have been proven to induce apoptosis of tumor cells. However, it remains largely unknown whether schiff base zinc complexes induce apoptosis in human cancer cells. Here, we synthesized a novel schiff base zinc coordination compound (SBZCC) and investigated its effects on the growth, proliferation and apoptosis of human osteosarcoma MG-63 cells. A novel SBZCC was synthesized by chemical processes and used to treat MG-63 cells. The cell viability was determined by CCK-8 assay. The cell cycle progression, mitochondrial membrane potential and apoptotic cells were analyzed by flow cytometry. The apoptosis-related proteins levels were determined by immunoblotting. Treatment of MG-63 cells with SBZCC resulted in inhibition of cell proliferation and cell cycle arrest at G1 phase. Moreover, SBZCC significantly reduced the mitochondrial membrane potential and induced apoptosis, accompanied with increased Bax/Bcl-2 and FlasL/Fas expression as well as caspase-3/8/9 cleavage. Our results demonstrated that the synthesized novel SBZCC could inhibit the proliferation and induce apoptosis of MG-63 cells via activating both the mitochondrial and cell death receptor apoptosis pathways, suggesting that SBZCC is a promising agent for the development as anticancer drugs.

Design, synthesis and anti-proliferative activity of novel coumarin derivatives linking Schiff base and aryl nitrogen mustard / 药学学报

To explore novel coumarin derivatives with more potent anti-proliferative activity, a series of novel compounds were designed and synthesized by linking Schiff base and N, N-bis (2-chloroethyl) amine pharmacophore of nitrogen mustards to the coumarin's framework. Their structures were confirmed by 1H NMR, MS and element analysis techniques. In vitro anti-proliferative activities were evaluated against HepG2, DU145 and MCF7 cell lines by the standard MTT assay. The results showed that some of the target compounds exhibited strong anti-proliferative activities against selected tumor cells, and compounds 7c, 7f, 7g, 7h and 7q were better than or equal to the activities of positive control, they deserved further development.

A study of in vitro antibacterial activity of lanthanides complexes with a tetradentate Schiff base ligand

<p><b>OBJECTIVE</b>To establish the antibacterial activity of lanthanides complexes with a tetradentate Schiff base ligand L.</p><p><b>METHODS</b>(N, N'-bis (1-naphthaldimine)-o-phenylenediamine) was prepared from the condensation of 2-hydroxy-1-naphthaldehyde with o-phenylenediamine in a molar ratio of 2:1. The antimicrobial activity of the resultant Ln (III) complexes was investigated using agar well diffusion and micro-broth dilution techniques; the latter was used to establish the minimum inhibitory concentrations for each compound investigated.</p><p><b>RESULTS</b>Most of Ln (III) complexes were found to exhibit antibacterial activities against a number of pathogenic bacteria with MICs ranging between 1.95-250.00 µg/mL. Staphylococcus aureus was the most susceptible bacterial species to [LaL(NO3)2(H2O)](NO3) complex while Shigella dysenteriae and Escherichia coli required a relatively higher MIC (250 µg/mL). The complexes La (III) and Pr (III) were effective inhibitors against Staphylococcus aureus, whereas Sm (III) complex was effective against Serratia marcescens. On the other hand, Gd (III), La (III) and Nd (III) were found to be more potent inhibitors against Pseudomonas aeruginosa than two of commonly used antibiotics. The remaining Ln (III) complexes showed no remarkable activity as compared to the two standard drugs used.</p><p><b>CONCLUSIONS</b>Tetradentate Schiff base ligand L and its complexes could be a potential antibacterial compounds after further investigation.</p>

Synthesis of New VO(II), Co(II), Ni(II) and Cu(II) Complexes with Isatin-3-Chloro-4-Floroaniline and 2-Pyridinecarboxylidene-4-Aminoantipyrine and their Antimicrobial Studies

The complexes of tailor made ligands with life essential metal ions may be an emerging area to answer the problems of multi drug resistance. The coordination complexes of VO(II), Co(II), Ni(II) and Cu(II) with the Schiff bases derived from isatin with 3-chloro-4-floroaniline and 2-pyridinecarboxaldehyde with 4-aminoantipyrine have been synthesized by conventional as well as microwave methods. These compounds have been characterized by elemental analysis, molar conductance, electronic spectra, FT-IR, FAB mass and magnetic susceptibility measurements. FAB mass data show degradation of complexes. Both the ligands behave as bidentate and tridentate coordinating through O and N donor. The complexes exhibit coordination number 4, 5 or 6. The Schiff base and metal complexes show a good activity against the bacteria; Staphylococcus aureus, Escherichia coli and Streptococcus fecalis and fungi Aspergillus niger, Trichoderma polysporum, Candida albicans and Aspergillus flavus. The antimicrobial results also indicate that the metal complexes are better antimicrobial agents as compared to the Schiff bases. The minimum inhibitory concentrations of the metal complexes were found in the range 10~40 microg/mL.

Synthesis of benzothiazole derivatives and their binding characteristics with beta-amyloid / 药学学报

Alzheimer's disease (AD) is a progressive neurodegenerative disease endangering human health seriously. Recent reports have revealed that beta-amyloid aggregates play a key role in the pathogenesis of AD. Thus, targeting the Abeta plaques benzothiazole derivatives were synthesized with the scaffold of the most promising imaging agent PIB ([11C]-6-OH-BTA-1, [11C]-2-(4-(methylamino)phenyl)-6-hydroxybenzothiazole) and C = N as linker to study the binding characteristics with the target protein through surface plasmon resonance (SPR) technique. These derivatives were synthesized through simple yet effective method with high yields and characterized by 1H NMR and FTIR. The binding properties (K(D)) were determined with Biacore X-100 instrument according to the fitting-plot curve. Compounds 3a and 3f showed high binding affinity for Abeta1-40. The results suggest that benzothiazole derivatives could be served as a scaffold to develop novel beta-amyloid imaging agents for the diagnosis of AD.

Synthesis and antiproliferative activities of novel 5'-Schiff-base group substituted psoralen derivatives / 药学学报

It was found that psoralen derivative could perform a Friedel-Crafts acylation smoothly with acetic anhydride to give 5'-acetylpsoralen in a 73% yield. In the presence of boron trifluoride etherate, 5'-acetylpsoralen reacted with both aromatic amines and aliphatic amine smoothly to afford 5'-Schiff-base group substituted psoralen derivatives in 72%-92% yields. The novel synthetic method has the advantages of cheap materials, mild reaction conditions, good yields and high regioselectivity in the Friedel-Crafts acylation. Cell viability assay by MTT demonstrates that some of the psoralen derivatives 6 have antiproliferative activities.

Effects of ternary complexes of copper with salicylaldehyde-amino acid Schiff base coordination compounds on the proliferation of BGC823 cells / 癌症

<p><b>BACKGROUND AND OBJECTIVE</b>The basic structure of salicylaldehyde-amino acid Schiff base compounds includes a C=N chemical bond. These compounds show significant antitumor activities in vitro when combined with a metal ion. This study investigated the effects and possible mechanisms of four salicylaldehyde-amino acid Schiff base copper ternary coordination compounds on the proliferation of human gastric cancer cell line BGC823.</p><p><b>METHODS</b>The BGC823 cells were treated with the four compounds (6B, 7B, 6P, and 7P). Cell proliferation was detected by MTT assay. Apoptosis and changes in the cell cycle were analyzed by flow cytometry. DNA damage was observed using a DNA ladder assay. The expression of p53 protein was determined by immunocytochemistry.</p><p><b>RESULTS</b>The proliferation of BGC823 cells was significantly inhibited by the four compounds and the effect was concentration-dependent. The half maximal inhibitory concentration (IC50) of 6B, 7B, 6P, and 7P for BGC823 cells were 18.10, 27.50, 3.61, and 3.45 micromol/L, respectively. Flow cytometry showed the four drugs induced apoptosis in BGC823 cells, which was confirmed by DNA ladder experiments. Flow cytometry also detected changed phases in the cell cycle from treatment with the compounds. The percent of cells in the G(0)/G(1) phase decreased and that of cells in the G1/S and G(2)/M phases increased, indicating that S-and G2-phase blockages exist. As shown by immunocytochemistry, the expression of p53 decreased in BGC823 cells treated with the four drugs, indicating the involvement of the p53 pathway to BGC823 cell apoptosis.</p><p><b>CONCLUSIONS</b>The four compounds showed significant activities on restraining proliferation of BGC823 cells in vitro, induced apoptosis, and caused changes in the cell cycle. This may be related to the downregulation of p53.</p>

Synthesis, characterization and catalytic activity of copper [II], nickel [II] and cobalt [II] complexes derived from novel hydrazone drivatives of oxamic hydrazide

A series of new coordination complexes of Cu[II], Ni[II] and Co[II] with omaxic hydrazide [L[1]], N,N' - [salicylidene]- oxamic hydrazide [L[2]] and N,N' - bis [naphthalidene] - oxamic hydrazide [L[3]] have been synthesized and characterized by elemental analysis, magnetic moment, IR, UV - Vis spectra nd molar conductance. The thermal behavior of the complexes was investigated by TG A and DTA techniques. The catalytic activity of the complexes to decolorize the Allura-Red [food dye] in presence of H[2]O[2] was studied

Magnesium [II] complexes of schiff bases of two beta- lactum antibiotics: synthesis and spectral characterization

Two Mg [II] complexes have been synthesized by condensing magnesium chloride with schiff bases of two different beta-lactams. In the present study, cephalexin and cefadroxil were the beta-lactams used for the synthesis of complexcs through schiff base formation. The estimation of carbon, hydrogen. nitrogen and sulphur, percentage of magnesium, and measurcments of IR spectra at 400- 4000cm[-1] indicated the formation of coordination compounds. The ratio of 2:1 complex of schiff base ligand to metal was confirmed through Job's of continuous variation. Further characterization of the complexes was carried out using UV spectra, mass spectra and conductance measurement

Antibacterial and Antifungal Studies on Some Schiff Base Complexes of Zinc(II)

Two Schiff base ligands L1 and L2 were obtained by the condensation of glycylglycine respectively with imidazole-2-carboxaldehyde and indole-3-carboxaldehyde and their complexes with Zn(II) were prepared and characterized by microanalytical, conductivity measurement, IR, UV-Vis., XRD and SEM. The molar conductance measurement indicates that the Zn(II) complexes are 1 : 1 electrolytes. The IR data demonstrate the tetradentate binding of L1 and tridentate binding of L2. The XRD data show that Zn(II) complexes with L1 and L2 have the crystallite sizes of 53 and 61 nm respectively. The surface morphology of the complexes was studied using SEM. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species Staphylococcus aureus, Escherichia coli, Klebsiella pneumaniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by the disc diffusion method. A comparative study of inhibition values of the Schiff base ligands and their complexes indicates that the complexes exhibit higher antimicrobial activity than the free ligands. Zinc ions are proven to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium.

Antimicrobial Activity of Some Schiff Bases Derived from Benzoin, Salicylaldehyde, Aminophenol and 2,4 Dinitrophenyl Hydrazine

The antibacterial and antifungal activities of three schiff bases were evaluated against some pathogenic bacteria and fungi. Parallel experiments were also carried out with standard drugs (Kanamycin for bacteria and Nystatin for fungi). Two compounds [N-(1-phenyl-2-hydroxy-2phenylethylidine)-2',4' dinitrophenyl hydrazine, abbreviated as PDH and N-(2-hydroxy benzylidine)-2'-hydroxy imine, abbreviated as HHP] showed significant antimicrobial activities. The rest one [N-(1-phenyl 2-hydroxy-2 phenyl ethylidine) 2'-hydroxy phenyl imine, abbreviated as PHP] showed moderate activity. All these three compounds were found to possess pronounced cytotoxic effect. These compounds can be considered as potent antimicrobial agents.

Synthesis of some novel 1, 3, 5-trisubstituted [1,2,4] triazole derivatives as potential antibacterial agents

In the present work, some new l,3,5-trisiubstituted [l,2,4]-triazole derivatives and their Schiff's bases were synthesized. The chemical structure of the target compounds was confirmed by IR, [1]H-NMR, [13]C-NMR, FAB-MS, EI-HRMS spectra and elemental analyses. The title compounds were tested for their in vitro antibacterial activity against Gram-positive and Gram-negative ones using ampicillin and nalidixic acid as reference drugs. Some of them showed antibacterial activity more significant than the reference drugs

Thermal stability of Ni [II] and cu [II] mixed ligand complexes derived from biologically important schiff bases, azoles and morpholine

Thermogravimetry [TG] and differential thermogravimefty [DTG] have been applied to the investigation of the thermal behavior of six mixed ligand complexes of Ni[II] and Cu[II] comprising the Schiff bases: o-hydroxyacetophenoneethanolimine [OHAE], N-salicylidene-o-iminophenol [SOP] and N-salicylidene-o-toluidine [SOT] as well as morpholine [Morph] and certain azotes. The azoles used are: 2-amino-thiazole [2-Atz], benzothiazole [Btz], 2-methylbenzothiazole [2-Mbtz], 3-methyl-2-selenoxobenzothiazole [3-Msbtz] and thiabendazole [Tbdz]. Heating the compounds first results in a release of the morpholine or the azoles. Kinetics of the decomposition reactions were studied using non-mechanistic equations

Synthesis and antitumor activity of C3 heterocyclic-substituted fluoroquinolone derivatives (I): ciprofloxacin aminothiodiazole Schiff-bases / 药学学报

To discover a novel antitumor lead compound derived from fluoroquinolone, C3 carboxyl group of ciprofloxacin (1) was replaced with heterocyclic ring to form cyclopropyl fluoroquinolone aminothiadiazole scaffold (2), then reacted with aromatic aldehydes to give the Schiff bases compounds (3a-3j). The structures of new compounds were characterized by element analysis and spectral data, and their in vitro antitumor activity against SMMC-7721, HL60 and L1210 cell lines was evaluated by MTT assay via the respective IC50 values. The bioactive assay showed that eleven thiadiazole-substituted ciprofloxacin derivatives displayed potential cytotoxicity against the tested cancer cell lines, where the IC50 values of compounds 3d and 3f reached micromolar concentration. Therefore, the C3 carboxyl group of fluoroquinolone is not necessary to antitumor activity. Functionally modified heterocycle-substituted fluoroquinolone as potent antitumor lead compound is valuable for further study.

Synthesis and antitumor activity of anthracene-9-carbaldehyde amino-s-triazole Schiff-bases with side-chain of S-acetic acid / 药学学报

To find out a novel lead compound from heterocyclic amine Schiff bases for developing new antitumor agents, each of (4-amino-5-substituted-s-triazol-3-ylthio) -acetic acids 2a-j was condensed with anthracene-9-carbaldehyde to obtain Schiff-bases of [4-(anthracen-9-yl methylene) amino] -5-substituted-s-triazol-3-ylsulfanyl] -acetic acids 3a-j. The structures of new compounds synthesized were characterized by elemental analysis and spectral data, and in vitro antitumor activity was also evaluated against CHO, HL60 and L1210 cell lines by MTT assay.