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In this article, four new Schiff base complexes of Mn(II), Co(II), Ni(II) and Cu(II) complexes have been synthesized with two different compositions as [M(L)2Cl2] · nH2O and [M(L)2(H2O)2]Cl2 · nH2O [where L1 = benzoin-o-amino benzoic acid (aromatic β amino acid) and L2 = benzoin bromo-o-amino benzoic acid (aromatic β amino acid); M = MnII, CoII, NiII and CuII; n = 1, 2 and 4]. These Schiff base complexes were discussed by many tool of analyses like elemental analysis, magnetic susceptibility, molar conductance, mass spectra, infrared spectra "IR," proton nuclear magnetic resonance "1H-NMR," electronic spectral and thermogravimetric analysis (TG/DTG). These complexes have an electrolytic nature within range of 78–174 Ω1 cm–1 mol –1 based on conductance measurements. Magnetic moment and electronic spectral results deduced that the geometry of Mn2+, Co2+ and Ni2+ and Cu2+ complexes has an octahedral configuration. The number of coordinated and uncoordinated water molecules for the synthesized complexes were calculated based on the thermal analysis technique. The kinetic thermodynamic data were estimated by using commonly integral equations of Horowitz-Metzger (HM) and Coats-Redfern (CR). In vitro the antimicrobial activity of both free L1 and L2 ligands in comparable with their metal complexes were evaluated. This study was strengthen by molecular docking against three protein receptors, which attributing to selected organisms already used in vitro study.

Synthesis and characterizations of new Mn(II), Co(II), Ni(II), Cr(III) and Fe(III) melatonin drug complexes have been studied. The melatonin ligand act as a monodentate ligand through nitrogen of the deprotonated –NH pyrrole ring. This was confirmed by infrared spectra and microanalytical analysis. The magnetic moments data approved the complexity of Mn(II), Co(III), Ni(III) as a square planar and Cr(III), Fe(III) as an octahedral geometry, respectively. The biological activity of the melatonin free ligand is lower than that of the respected metal complexes. Thus, this indicates that the complexity is more effective than the antimicrobial activities of melatonin ligand.

A new synthesized sodium salt of [2Z,2′Z)-4,4′-(1,2-phenylene bis(azanediyl))bis(4-oxobut-2-enoic acid] (CI) is tested as corrosion inhibitor for carbon steel (CS) in 0.5 M H2SO4 solutions via electrochemical techniques. The results open circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy show that new compound has excellent inhibiting effect for CS corrosion in the corrosive sulfuric acid medium with efficiencies of approximately 99% at an optimum 150 ppm concentration. The results proved that the inhibitor is of a mixed cathodic/anodic type. Density function theory (DFT) is helpful in finding the relevancy of quantum chemical descriptors to the performance of this molecule as corrosion inhibitors. Some quantum descriptors such as EHOMO; energy of the highest occupied molecular orbital, ELUMO; energy of the lowest unoccupied molecular orbital, ΔE; the energy gap, η; Global hardness, S; global softness, I: ionization potential, A: electron affinity, X: absolute electronegativity, ω; global electrophilicity index, ΔEBack-donation; the back donation, f+, f; Fukui indices for local nucleophilic and electrophilic attacks were investigated. The feedback of descriptors calculation proves that the title molecule can perform as a corrosion inhibitor. Keywords: DFT, Quantum chemical descriptors, Fukui function, Local reactivity, Corrosion inhibition, Pickling solution

Mixed ligand vanadyl(II) complexes of orotic acid and six different amino acids (isoleucine, threonine, proline, phenylalanine, lysine, and glutamine) have been synthesized. Vanadyl(II) orotate mixed ligand complexes are studied on the basis of conductivity, FTIR, UV-Vis, TG-DTG-DTA, magnetic moments, solid powder XRD, SEM, and TEM measurements. These non-electrolyte complexes are of 1 : 1 : 1 stochiometry. The major goal of this article is design and synthesis of new insulin alternative anti-diabetic drug. The insulin hormone and blood glucose level, lipid profile, liver and kidney functions, and superoxide dismutase antioxidant (SOD) are the factors to identify efficiency of the new synthesized compounds as antidiabetic drug agents.

Mononuclear Au(III) Schiff base complexes are synthesized by the reaction of 4-aminoantipyrine with hydrazine. The chemical structures of new Schiff bases and their Au(III) complexes are elucidated from their conductance, XRD, and spectroscopic (IR, UV-Vis, 1H, and 13C NMR) data. Au(III) Ion is coordinated with the synthesized Schiff bases via four nitrogen atoms of the antipyrine and azomethine groups. Au(III) Complexes are electrolytes with three uncoordinated Cl− ions, and have a square planar geometry. Their morphology is characterized by SEM and TEM methods. Cytotoxic effect of the complexes is tested against human breast cancer (MCF-7) and hepatocellular carcinoma (HepG-2) cell lines.

Aim: This research paper is aimed at designing a novel insulin alternative for the treatment of diabetes. Materials & methods: Six novel vanadyl(II) compounds, [(AMP−2)(VO+2)(AA n −1)]·NH4 +1, were synthesized from an equimolar ratio of adenosine monophosphate, VOSO4 and amino acids (AA n ). Results: The magnetic moments and electronic spectra revealed the square pyramidal geometrical structure of the complexes. In an in vivo study, the insulin levels, blood glucose levels, lipid profiles and histology of the pancreas and liver of the animals treated with the complexes were similar to those of healthy control animals, unlike the untreated and vanadyl sulfate(II)–treated diabetic ones. Conclusion: The data gathered in the current research illustrated that vanadyl(II)-AMP-amino acid (AA) mixed-ligand complexes can function as antidiabetic agents.

A series of a novel 2, 3'-bipyrrole derivatives was synthesized via the reaction of chalcone, 1-(furan-2-yl)-3-(1H-pyrrol-2-yl) prop-2-enone, with different amino acids in an alkaline medium. The reaction proceeds throughout the condensation of the amino acids with chalcone to give imine intermediate consequent by decarboxylation, and then intramolecular cyclization to yield 2, 3'-bipyrrole derivatives. Antitumor activity of the newly synthesized bipyrrole derivatives was evaluated against different six cancer cell lines, and compounds 3d, 3e, 3c and 3h showed the strongest anticancer activity amongst the studied compounds. Compound 3h showed the broadest spectrum of anticancer activity against all cell lines tested. The results of this work offer a basis for further study of selected 2, 3'-bipyrrole derivatives as antitumor agents.

An operationally simple and efficient method of synthesis of novel 1,5-disubstituted tetrazoles with high yields from easily accessible 2-(2-benzamido-3-arylacrylamido)acetate under mild conditions is developed. Anticancer and anti-microbial tests of the new tetrazole derivatives have been carried out.

A set of 1,2,3-triazole incorporated quinolone antibiotic conjugates 10–15, 17–19 were synthesized via microwave assisted click chemistry technique. Some of the aryl-substituted conjugates 17–19 show promising antibacterial properties against the tested Gram-positive (S. aureus and S. pyogenes) and Gram-negative bacteria (S. typhi) with potency higher than that of the parent antibiotics 1–3. 2D-QSAR modeling supports the observed biological properties.

The experiment was performed in the central laboratory for aquaculture research, Egypt. Experimental fish about 10.2 g Nile tilapia were divided into four different treatments in different ratios, and fed on 25% protein pellets for 120 days at 3% of body weight. Some parameters like some digestive enzymes (amylase and lipase), glucose, cortisol, insulin, growth hormone, iron and total binding iron capacity were measured in blood serum; the 4th treatment showed the minimum value for theses measurements except for glucose and cortisol 153.6±9.2 mg/dl and 176.3±5.2 ng/ml, respectively. Haemoglobin showed the highest and minimum value (7.63±0.03 g/dl & 6.27±0.03 g/dl) in treatments (1and 4) respectively. Erythrocytes count showed the highest value 2.52±0.01(X106/Cmm) in the first treatment, while the lowest value 2.09±0.03 (X106/Cmm) was recorded among treatment (4). Water samples for physico-chemical analysis were monitored bi-weekly during the study period then collected and tabulated in one mean. The growth performance of experimental fishes was significantly decreased with increasing fish density.

GLYCINE (Gly) complexes play an important role in human life. Zn(II), Cu(II), Ni(II), Fe(III), Mn(II), and Cr(III) complexes were synthesized with glycine (Gly). These complexes were characterized by infrared spectroscopy (FT-IR). Based on the stoichiometric data, Gly form a chelate complex in a bidentate fashion at a 1:3 ratio with the trivalent metal ions [Cr(III), Fe(III)] and a 1:2 ratio with the divalent ones [Mn(II), Ni(II), Cu(II) and Zn(II)]. Metal oxides were derived from each of the Gly complexes using thermal decomposition at 800°C. FT-IR analysis of the resulting solids revealed their formation in pure form.

Five analogues of Polymyxin E1 antibiotic were synthesized via Fmoc- solid phase peptide synthesis (SPPS) strategy using Biotage® Initiator+Alstra™ microwave peptide synthesizer. The aim of this work is to study the importance of the cyclization conditions of the lactam ring on the purity and yield of the final compounds. For this purpose, replacing L-Thr10 with L-Asp allowed the application of different cyclization methodologies. In all analogues, the Dab5,8,9 residues were replaced with Arg, while the Dab4 residue involved in lactam cyclization was replaced with Lys. Modification of the linear tripeptide tail was applied to two of the analogues. The obtained compounds were characterized with different spectroscopic techniques and will be tested for their antimicrobial activity.

A series of erythropoietin hormone analogues (1–9) were synthesized by a modern method, microwave-assisted modified solid-phase peptide synthesis, on polystyrene polyethylene glycol graft copolymer. Peptide 9 was cleaved from the polymer to give peptide 10. Measurement of haematological data for analogue 10 gave good results comparable with those of the original hormone. The structures of the new peptides were confirmed by amino acid analysis and use of spectroscopic evidence.

The corrosion inhibition efficiency of α-brass was evaluated in unpolluted and sulfide polluted 3.5% NaCl. The Sodium (Z)-4-Oxo-4-p-Tolyl-2-Butenoate (SOTB) has been used as safe organic corrosion inhibitor instead of benzotriazole. The electrochemical methods were used to monitor the effect of inhibitor on corrosion inhibition of brass. The results showed that this inhibitor act as cathodic and anodic inhibitor for the surface of brass in both chloride and sulfide polluted medium. Brass electrodes were subjected to characterization by SEM and EDS to prove the probable mechanism. The inhibition efficiency and the persistence of protective film are depends on the inhibitor concentration in both chloride and sulfide media.

A variety of N -[(ethyl-4,6-diaryl-3-pyridinecarboxylate)-2-yl]amino acid esters 6a – h were synthesized through the reaction of 2-bromonicotinates 4 with a number of primary amino acid ester hydrochlorides 5 in refluxing tetrahydrofuran in the presence of triethylamine as dehydrohalogenating agent. Similarly, reaction of 4 with N -glycylglycine ethyl ester hydrochloride 7 ‘as a representative example of dipeptide derivative’ afforded smoothly the corresponding N -[(ethyl-4,6-diaryl-3-pyridinecarboxylate)-2-yl]- N ′-glycylglycine ethyl ester analogues 8 . However, reaction of 4 with 5 in refluxing pyridine yielded the unexpected 2-aminonicotinate esters 9 . Vasodilation activity screening for the synthesized nicotinate esters was investigated in vitro on the contractile response of vascular thoracic aorta smooth muscle from Wistar rats, where all the tested compounds exhibit considerable vasodilatory properties. In addition, few prepared compounds especially, 6b , 6h and 9b reveal remarkable vasodilation potency (IC 50 ).

A variety of N-[(4,6-diaryl-3-pyridinecarbonitrile)-2-yl] amino acid esters 2-4 were synthesized through the reaction of 2-bromo-3-pyridinecarbonitriles 1 with the appropriate alpha-amino acid ester hydrochloride in refluxing dioxane in the presence of triethylamine as dehydrohalogenating agent. Similarly, N'-glycylglycine analogues 5 were obtained through the reaction of 1 with the dipeptide ester. On the other hand, attempts were made towards the construction of amino acid derivatives 7 through the reaction of 1 with aqueous solution alpha-amino acids 6 in refluxing pyridine, but were unsuccessful, and instead the unexpected 2-amino-3-pyridinecarbonitriles 8 were isolated. The fluorescence properties of the newly synthesized pyridines 2-5 were evaluated. Some of the prepared compounds show considerable antibacterial activity.