Kinetic H/D exchange study of Co(III) coordination compounds of diazines using NMR spectroscopy

The Co(III) diazines complexes having composition (NH3) 5CoPhtz)(ClO4), (1) (Phtz = phthalazine), (NH 3)5CoPydz)(ClO4)3 (2) (Pydz = pyradazine), (NH3)5Co(3-Me-Pydz)(ClO4) 3 (3) (3-Me-Pydz = 3-methyl pyradazine) and (NH3) 5Co(3-MePhtz)(ClO4)3 (4) (3-MePhtz = 3-methyl phthalazine), (NH3)5Co(ImH)(ClO4), (5) (ImH = imidazole), (NH3)5Co(NMeIm)(ClO4) 3 (6) (N-MeIm = N-methylimidazole) undergo OD--catalyzed H/D exchange at the ortho position of the coordinated site. Rate constants for H/D exchange of these complexes at 25°C or 60°C were obtained in alkaline D2O solution using NMR spectroscopy. Reaction rate for (NH3)5CoPhtz)(ClO4)3, (NH 3)5CoPydz)(ClO4)3, (NH 3)5Co(3-MePydz)(ClO4)3 and (NH3)5Co(3-MePhtz)(ClO4)3 at 25°C are faster compared to (NH3)5Co(ImH)(ClO 4)3, (NH3)5Co(N-MeIm)(ClO 4)3 (7). However (NH3) 5CoImCo(NH3)5Br5 complex does not H/D exchange at 60°C even in strong alkaline D2O solution

Synthesis of Some Benzimidazole-substituted Benzotriazoles

2-Alkylsubstituted benzimidazoles (3a–h) were prepared from the acid-catalyzed reaction of 4-methyl-1,2-phenylenediamine with corresponding carboxylic acids. Addition of these benzimidazoles to N-chloromethylbenzotriazole in the presence of sodium amide under reflux conditions gave the novel benzimidazole-substituted benzotriazoles (5a–f). IR and 1HNMR spectroscopy and elemental analysis were used for the identification of these compounds.Keywords: Phenylenediamine, benzimidazole, benzotriazol

Lemon Juice as a Natural Catalyse for Synthesis of Shiff’s base: A Green Chemistry Approach

The advantages of the use of natural catalysts are eco-friendly, inexpensive, high yields, nonhazardous and short reaction times. The utilization of green chemistry techniques is the elimination of solvents during chemical processes or the replacement of hazardous solvents with environmentally friendly solvents. Green chemistry has used for the synthesis of Schiff bases. Synthesis of Schiff base is carried out the mixture of aldehyde (or ketone) and amine in organic medium with or without an acid catalyst. He presents study Uses Lemon juice as a natural and eco-friendly catalyst in the green chemistry investigated. The synthesized product was characterized by its physical properties, melting point, TLC and then subjected to the in vitro antibacterial activities against gram-positive and gram-negative strains of microbes

Synthesis and biological activity of some heterocyclic compounds contains N-benzylidene heterocycle and beta-lactam moiety

A number of N-benzylidene heterocycle derivatives have been synthesized and their antibacterial activities tested. The new chemical structures synthesized compounds were verified on the basis of spectral and elemental methods of analyses.the antimicrobial activity of the compounds was done by disc diffusion method We synthesized two different types of compounds, a combination of compounds based on the structure of isatin and other compounds based on the structure of thiazole. Synthesis of thiazole was performed using green chemistry method and a three-step reaction was used in the synthesis of isatin compounds. We used the Stoell-Becker method to synthesize compounds based on the isatin structure. The synthesized product was characterized by its physical properties, melting point, TLC and then subjected to the in vitro antibacterial activities against gram-positive and gram-negative strains of microbe

Synthesis, structural characterization and biological activity of Cu(II), Co(II) and Ni(II) complexes derived from 2-(thiazol-2-ylimino)thiazolidin-4-one ligand

A novel series of metal complexes of 2-(thiazol-2-ylimino) thiazolidin-4-one ligand were prepared; the corresponding ligand was synthesized from reaction 2-Chloro-N-(thiazol-2-yl) acetamide with ammonium thiocyanate. The complexes are characterized by FTIR, UV-Vis, molar conductance and mass spectroscopy. The low molar conductance values indicate that the complexes are non-electrolytes.Spectroscopic studies confirmed that the ligand bonded to the metals through the sulphur atoms. Coordination number of copper and nickel complexes is four with square planar geometry, while the cobalt complex has octahedral geometry.In vitro antibacterial activity of ligand and its metal complexes was evaluated using well diffusion method and compared to the standard drug (tetracycline). The antibacterial activitywas examined against Escherichia coli, and pseudomonas aeruginosa, as gram negative bacteria and Staphylococcus aureus as gram positive bacteria. It was found that Nickel complex has the highest antibacterial activity among the synthesized compounds with Zone inhibition diameter in the range 25-29 mm

One-pot synthesis of tetrahydropyrimidines catalyzed by zeolite

A simple one-pot synthesis of various tetrahydro pyrimidines in the presence of NaY zeolite, as an efficient catalyst, is reported. The multicomponent reaction was carried out by a three-component coupling of 1,3-diketone, aldehyde and urea/thiourea in the presence of the catalyst to give 1(a-k). The catalyst could be reused several times. Further reaction of these pyrimidines with phosphorus oxychloride gave corresponding N-formylated compounds

Using of Naproxen drug for novel synthesis of 4-thiazolidinone derivatives and application of these drugs as no steroidal anti-inflammatory drug (NSAIDs) and as anti-epileptic agent

Non-steroidal anti-inflammatory drugs (NSAIDs) are now one of the most frequent drugs used in treatment of pain, inflammation and fever. In this study the aim is the synthesis of derivatives of 4-Tiazolidinon from naproxen with the possible anti-pain effects, and the main purpose of providing these derivatives is to achieve a compound with more anti-pain power and less side effects in comparison with applied drugs in clinics. Synthesis of these derivatives is done on chloride in presence of a group of new liquids like recyclable ionic liquids choline chloride, which the main advantages of these ionic liquids are the cheapness, availability, being non-toxic, and easy recyclability. This reaction was done in four stages. All the structures were verified by using data of spectrum testing, 1H-NMR, FT-IR

An Efficient and Convenient Protocol for the Synthesis of Optically Active 1,2,4-Triazolo-[3,4-b]-[1,3,4]-Thiadiazole, 1,3,4-Oxadiazole and 1,3,4-Thiadiazole Derivatives having L-Amino Acid Moieties

A series of novel bis triazolothiadiazole, 1,3,4-oxadiazole and 1,3,4-thiadiazole derivatives attached to L-amino acid moieties were synthesized in good yields using a simple and practical method. The structure of all synthesized compounds was confirmed by IR, 1H NMR, 13C NMR spectroscopy and elemental analysis.Keywords: Amino acid, triazolothiadiazole, 1,3,4-oxadiazole, 1,3,4-thiadiazole, phosphorus oxychloride, triazol