Bashir Ahmad Dar

Chemistry and Biology of Indoles and Indazoles: A Mini-Review

The present review article is related with the method of preparation, importance and medicinal application of indole and indazoles. The studies of heterocycles is an evergreen field in the branch of organic chemistry and always attract the attention of chemists working not only in the area of natural products but also in the synthetic chemistry. Moreover many useful drugs have emerged from the successful investigation carried out in this branch. The derivatives of indoles and indazoles exhibits antibacterial, anticancer, antionidants, anti-inflammatory, antidiabetic, antiviral, atniproliferative, antituberculosis, antispermetogenic activity, antipsychotic drugs etc.

[1, 2, 4]-Oxadiazoles: Synthesis and Biological Applications

In the present article synthesis and medicinal applications of [1, 2, 4] oxadiazoles are reviewed. The oxadiazoles have a wide range of applications such as Antitussive, Anti-inflammatory, Anaesthetic, Vasodilator, anthelmintic, antiallergic, antiplatelet effects in vitro, antithrombotic properties in vivo, etc. Many researchers have synthesized novel heterocyclic compounds containing oxadiazoles with the concept of bioisosterism.

Solvent-free, scalable and expeditious synthesis of benzanilides under microwave irradiation using clay doped with palladium nanoparticles as a recyclable and efficient catalyst

Benzanilide synthesis through amide bond formation was effectively carried out by palladium-doped clay catalyst using microwave irradiation under solvent-free conditions. Products were obtained with excellent yield in very short reaction time and only a small amount of the catalyst was used. The catalyst could be separated easily and recycled several times with insignificant loss in catalytic activity. No column purification was required and the products were purified by the crystallization method. The heterogeneous character of the catalyst in a ligand-free, solvent-free and base-free system supports for a practical and environmentally benign process.

Fe–Al/clay as an efficient heterogeneous catalyst for solvent-free synthesis of 3, 4-dihydropyrimidones

AbstractA practical, efficient, environmentally benign condensation of an aldehyde, ethylacetoacetate and urea/thiourea for the synthesis of 3, 4-dihydropyrimidinones, employing Fe–Al/clay composite catalyst is described. The process has been carried out under solvent-free conditions in the presence of very small amount of catalyst. The catalyst used for this process is easy to prepare, easy to handle, cost effective, easy to separate and recyclable at least up to 5 cycles with good to excellent yield. Graphical AbstractA heterogeneous catalyst (Fe–Al/clay composite) has been prepared by a simple procedure from easily available materials and applied for the synthesis of 3, 4-dihydropyrimidinones, from aldehyde, ethylacetoacetate and urea/ thiourea under solvent-free conditions.

Pore-engineered silica–alumina: texture, acidity, and activity for conversion of longifolene to isolongifolene

Pore-engineered silica–alumina was synthesized for the conversion of longifolene to isolongifolene, and the effects of texture and surface properties on the activity were examined. The acidity and texture of the modified silica–alumina play a vital role in governing the catalytic isomerization of longifolene to isolongifolene. A conversion of 97% of longifolene with 95% selectivity has been achieved.Graphical abstract

Benzimidazole Derivatives as Potential Antimicrobial and Antiulcer Agents: A Mini Review

Here in we report the number of strategies for the synthesis of differently substituted benzimidazole derivatives. The protocols involved in the syntheses of these derivatives were one-pot or multi-component. The characterization studies of these derivatives were carried by using different spectroscopic techniques (1H NMR, 13C NMR and MS) and elemental analyses. The biological screening studies revealed that these benzimidazole derivatives show potential antibacterial as well as antifungal behavior. These benzimidazole derivatives not only depicted potential antiulcer properties but also showed moderate to good anticancer/cytotoxic behavior against different cancer cell lines.

Gold Chloride (AuCl 3 ) Catalyzed Expeditious Homocoupling of Terminal Alkynes at Ambient and Solvent Free Conditions: Impact of Sodium Acetate on the Reaction Yield

Homocoupling of terminal alkynes to 1, 3-diynes has been investigated, using AuCl3 as catalyst under mild and operationally simple conditions. Effect of different organic and inorganic bases on the product yield and the reaction time were also studied. The catalyst is efficient, furnishes good to excellent yield of the desired products with organic bases and Sodium acetate was found to be the most effective base under solvent free conditions at room temperature.