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A series of four mixed ligand complexes synthesized by reacting benzoylacetone and salicylaldehyde with different metal chlorides in ethanolic medium, were tested for their antimicrobial studies and indicated that the compounds are active against microorganisms used (Escherichia coli, Staphylococcus aureus, and Candida albicans) when compared with the activity of the reference or standard drugs (Erythromycin and Suptrin).Keywords: Antimicrobial, Synthesis, Ligands, Complexes

Condensation of Ethyl 2-methylacetoacetate and ethylenediamine yield 88.7% of Dimethyl-7,14-Diphenyl-1,4,8,11-Tetraazacyclotetradeca-4,7,11,14-Tetraene with a condense chemical formula as C 18 H 32 N 4 O 2 , and a molecular weight of 336.47. The complexes were prepared by the adsorption of heavy metals (Fe, Cu, Cd, Co and, Pb) from wastewater samples obtained from Kofar sauri, Lambun Dan Lawal and Youth craft village. The compounds were investigated by solubility, conductivity, melting/decomposition point, Atomic Absorption Spectroscopy, Infrared spectroscopy and Uv-visible spectroscopy. The Ligand 003 shows IR peak of υ(C=N) at 1633cm -1 , and a shift was observed to a lower peak as a result of adsorption of the heavy metals by the ligand, which is signifying the formation of the complexes. AAS results indicates high concentration of Cu in each case when compared, the rest of the metals varying at different level of concentration in the compounds. Cu may best fit the center of the ligand cavity having a concentration beyond computing with the rest of the metals. Key words : Schiff base, wastewater, heavy metals

A series of four mixed ligand complexes were synthesized by reacting benzoylacetone and salicylaldehyde with different metal chlorides in ethanolic medium. The complexes have been characterized by molar conductance measurements and spectral techniques such as IR and Uv-visible electronic spectra. Decomposition temperature was also determined. The results indicated that the compounds have bands at 400-500cm-1, with very sharp melting points. This proved the formation of metal-oxygen bond, purity and high thermal stability of the compounds that could lead to a high antimicrobial activity.Keywords: Adduct Synthesis, Ligands, and Complexes

Herein we report the synthesis, characterization and antioxidant activity of the Schiff base ligands (E)-4-bromo-2-((2-piperazine-1-yl)ethylimino)methylphenol and 2,2’-(1E,1E’)-cyclohexane1,2-diylbis(azan-1-yl-1-ylidene))bismethan-1-yl-1-ylidene)bis (4-bromophenol) and their complexes of copper (II) ion. Antioxidant activities of the copper complexes were studied by ferric reducing antioxidant power (FRAP) assay according to the procedure reported by Benzie and Strain 1 which considered the reduction of ferric tripyridyl triazine complex to a ferrous complex at low pH by monitoring the change in absorption at 593nm. The overall results showed an increased in antioxidant activity with the increase in steric crowd. Similarly, the ligands show high activity than the complexes.

The development of metal-based agents has had a tremendous role in the present progress in cancer chemotherapy. One well-known example of metal-based agents is Schiff based metal complexes, which hold great promise for cancer therapy. Based on the potential of Schiff based complexes for the induction of apoptosis, this study aimed to examine the cytotoxic and apoptotic activity of a CdCl2(C14H21N3O2) complex on HT-29 cells. The complex exerted a potent suppressive effect on HT-29 cells with an IC50 value of 2.57 ± 0.39 after 72 h of treatment. The collapse of the mitochondrial membrane potential and the elevated release of cytochrome c from the mitochondria to the cytosol indicate the involvement of the intrinsic pathway in the induction of apoptosis. The role of the mitochondria-dependent apoptotic pathway was further proved by the significant activation of the initiator caspase-9 and the executioner caspases-3 and -7. In addition, the activation of caspase-8, which is associated with the suppression of NF-κB translocation to the nucleus, also revealed the involvement of the extrinsic pathway in the induced apoptosis. The results suggest that the CdCl2(C14H21N3O2) complex is able to induce the apoptosis of colon cancer cells and is a potential candidate for future cancer studies.

The current study described the synthesis and the in vivo acute oral toxicity evaluations in Sprague Dawley rats. The compounds were characterized by elemental analyses, LC-MS, FTIR, (1)H NMR, (13)C NMR and UV-visible spectroscopy. In the acute toxicity study, a single administration of the compounds was performed orally to the rats at the single doses of 2000 mg/kg and they were then monitored for possible side effects, mortality or behavioral changes up to 14 days. The serum level of aspartate (AST), alanine aminotransferases (ALT), alkaline phosphate (ALP), triglyceride, high density lipoprotein (HDL), immunoglobulins (GAM) and the C-reactive proteins did not significantly change. The hematological indices white blood cells (WBC), haematocrit (HCT), red blood cells (RBC), mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC), and mean corpuscular hemoglobin (MCH) were within the normal range. The renal function indices examined were also within the reference range. Generally, the compounds exhibited low toxic effects as required for further in vivo therapeutic studies.

Zinc complexes were reported to have anti-ulcer activity and used as drug for the treatment of gastrointestinal disorders. A novel compound dichlorido-zinc(II)-4-(2-(5-methoxybenzylidene amino)ethyl)piperazin-1-iumphenolate (ZnHMS) was synthesized, characterized and evaluated for its gastroprotective activity against ethanol-induced ulcer in rats. Gross and microscopic lesions, histochemical staining of glycogen storage, biochemical and immunological parameters were taken into consideration. Oral administration of ZnHMS (30 and 60 mg/kg; 14 days) dose-dependently inhibited gastric lesions. It significantly increased the mucus content and total acidity compared to the control group (P < 0.01). Serum levels of aspartate (AST), alanine (ALT) transaminases, pro-inflammatory interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-a) and anti-inflammatory interleukin-10 (IL-10) in the rats exposed to ethanol induced ulceration have been altered. ZnHMS considerably enhances (P < 0.05) the protection of gastric epithelia by modulating the acute alterations of AST, ALT, IL-6, IL-10, TNF-a and stomach glycogen. Interestingly, ZnHMS did interfere with the natural release of nitric oxide. In addition, acute toxicity study revealed no abnormal sign to the rats treated with ZnHMS (2000 mg/kg). These findings suggest that the gastroprotective activity of ZnHMS might contribute in adjusting the inflammatory cytokine-mediated oxidative damage to the gastric mucosa.

The compound dichlorido-copper(II)-4-(2-5-bromobenzylideneamino)ethyl) piperazin-1-ium phenolate (CuLBS) was synthesized, characterized and screened for acute toxicity and protective activity against ethanol-induced gastric mucosal injury in rats. Gross microscopic lesions, biochemical and immunological parameters and histochemcial staining of glycogen storage were taken into consideration. Oral administration of CuLBS (30 and 60 mg/Kg) for two weeks dose-dependently flattened gastric mucosa, significantly increased gastric mucus and total acidity, compared with control group (P < 0.01). Serum levels of liver enzymes aspartate (AST) and alanine transaminases (ALT), pro-inflammatory (IL-6 and TNF-α) and anti-inflammatory (IL-10) cytokines in the rats exposed to ethanol induced ulceration have been altered. Administration of CuLBS showed considerable (P < 0.05) protection against ulceration by modulating the acute alterations of cytokines AST, ALT and stomach glycogen. Interestingly, CuLBS did not interfere with the natural release of nitric oxide. CuLBS alone (60 mg/Kg) did not exhibit any ulcerogenic effect as assessed using Adami’s scoring scale. An acute toxicity study showed that rats treated with CuLBS (1,000 and 2,000 mg/Kg) manifested no abnormal signs. These findings therefore, suggested that the gastroprotective activity of CuLBS might contribute in modulating the inflammatory cytokine-mediated oxidative damage to gastric mucosa.

The development of metal-based agents has had a tremendous role in the present progress in cancer chemotherapy. One well-known example of metal-based agents is Schiff based metal complexes, which hold great promise for cancer therapy. Based on the potential of Schiff based complexes for the induction of apoptosis, this study aimed to examine the cytotoxic and apoptotic activity of a CdCl2(C14H21N3O2) complex on HT-29 cells. The complex exerted a potent suppressive effect on HT-29 cells with an IC50 value of 2.57 ± 0.39 after 72 h of treatment. The collapse of the mitochondrial membrane potential and the elevated release of cytochrome c from the mitochondria to the cytosol indicate the involvement of the intrinsic pathway in the induction of apoptosis. The role of the mitochondria-dependent apoptotic pathway was further proved by the significant activation of the initiator caspase-9 and the executioner caspases-3 and -7. In addition, the activation of caspase-8, which is associated with the suppression of NF-κB translocation to the nucleus, also revealed the involvement of the extrinsic pathway in the induced apoptosis. The results suggest that the CdCl2(C14H21N3O2) complex is able to induce the apoptosis of colon cancer cells and is a potential candidate for future cancer studies.

This study describes the protective effects of piperazine derived compounds against aspirin induced gastric injuries and evaluated the role of nitric oxide, inflammatory cytokines and serum level of aspartate aminotransaminases (AST), alanine aminotransaminases (ALT), high density lipoprotein (HDL) and malondialdehyde (MDA). The oral administration of the compounds at doses 30 and 60 mg/kg protected the gastric against the nectrotizing effects of aspirin. The level of nitric oxide (NO) was elevated in the group pretreated with the compounds. The results also showed that pre-treatment with piperazine compounds has led to the decrease in the amount of MDA and increased the activity of AST, ALT and HDL. In conclusion, pre-treatment with piperazine derived compounds; (E)-2-(1-(2-(piperazin-1-yl)ethylimino)ethyl)phenol (2HP), (E)-4-(1-(2-(piperazin-1-yl)ethylimino)ethyl) benzene-1,3-diol (DHP) and their zinc complexes has provided a significant protection to the gastric from damaging effects of aspirin.

a b s t r a c t Ethnopharmacological relevance: Turnera diffusa Willd. ex Schult. has been used for the treatment of several human disorders including peptic ulcer. Objectives of the study: The current study is an attempt to evaluate the anti-ulcerogenic activities of arbutin, a major constituent of Turnera diffusa on two ulcer models. The possible involvement of lipid peroxidation, nitric oxide, IL-6, IL-10, TNF- and mucus barrier mechanism has been investigated. Materials and methods: Effects of arbutin on ulcer index, gastric juice acidity, mucus content and histo- chemistry, gross and histological gastric lesions, nitric oxide, cytokines levels (IL-6, IL-10 and TNF-), and thiobarbituric acid reactive substances (TBARS), were evaluated in aspirin or ethanol-induced ulcer in vivo. Acute toxicity of arbutin was also examined in rodent model. MTT assay was used to assess the cytotoxicity of the compound on normal liver cells (WRL-68). Results: Pre-treatment with arbutin or omeprazole protected the gastric mucosa as seen by reduction in ulcer area and mucosal content, reduced or absence of edema, inflammation and leucocytes infiltration on both models. Arbutin significantly (P < 0.05) lowered the elevated TBARS level into gasteric homogenate. Arbutin did not produce significant inhibition of NO. This natural compound has modulated the levels of interleukin-6, interleukin-10 and TNF-. No in vitro or in vivo toxicities for arbutin were observed. Conclusion: Thus it can be concluded that Turnera diffusa possesses anti-ulcer activity, which could be attributed to lipid peroxidation inhibitory, immuno modulatory and anti-oxidant mechanisms of arbutin but not to the intervention with nitric oxide inflammation pathway. © 2012 Elsevier Ireland Ltd. All rights reserved.

In the title compound, [CuCl(2)(C(11)H(17)N(3))], the Cu(II) ion is five-coordinated with a distorted square-pyramidal configuration. The three N atoms of the Schiff base ligand and one Cl atom are located in the basal plane, whereas the other Cl atom is apically positioned.

In the title compound, C6H17N32+·2ClO4−, the piperazine ring adopts a chair conformation with the ethylammonium fragment occupying an equatorial position. In the crystal, the dications and perchlorate anions are linked through N—H...O hydrogen bonding and weak C—H...O hydrogen bonding into a three-dimensional supramolecular network.

In the title compound, [CdCl2(C14H21N3O2)], the Schiff base ligand chelates the CdII ion in an N,N,O-tridentate fashion. Two Cl atoms complete a distorted square-pyramidal coordination environment around the metal atom. In the crystal, adjacent molecules are linked through C—H...π interactions into infinite chains along the a axis. The molecules are further connected into a three-dimensional network via N—H...O, N—H...Cl and C—H...Cl interactions. The ethylene group is disordered over two sets of sites in a 0.520 (10):0.480 (10) ratio.

In the title compound, C(20)H(24)N(4), the cyclo-hexane ring adopts a chair conformation with the two imine groups linked at equatorial positions. The two halves of the mol-ecule are related by a crystallographic twofold rotation axis. The dihedral angle between the pyridine rings is 75.73 (3)°.