Construction of five- and seven-membered rings facilitated by alkyne-azide functionality: access to quinoline fused triazolo-azepines.

The synthesis of novel quinoline-fused triazolo-azepine derivatives has been reported using an intramolecular 1,3-dipolar azide-alkyne cycloaddition strategy. This method possesses considerable potential to synthesize five- and seven-membered rings in high yields (65-87%) without the necessity of metal catalysts or additives. Additionally, this methodology was applicable to pyridine and tetralone based adducts to afford triazolo-azepine derivatives.

An efficient metal-free and catalyst-free C-S/C-O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides.

An operationally simple and metal-free approach is described for the synthesis of pyrazole-tethered thioamide and amide conjugates. The thioamides were generated by employing a three-component reaction of diverse pyrazole C-3/4/5 carbaldehydes, secondary amines, and elemental sulfur in a single synthetic operation. The advantages of this developed protocol refer to the broad substrate scope, metal-free and easy to perform reaction conditions.

Sustainable utilization of food waste for bioenergy production: A step towards circular bioeconomy.

The population growth, along with lifestyle changes, has resulted in unprecedented levels of food waste at all phases of the supply chain, including harvest, packing, transportation, and consumption. Conventional practices involve dumping of food waste with municipal garbage. However, these methods have serious environmental and health consequences.

Pyrrolo[2,1-f][1,2,4]triazine: a promising fused heterocycle to target kinases in cancer therapy.

Cancer is the second leading cause of death worldwide responsible for about 10 million deaths per year. To date several approaches have been developed to treat this deadly disease including surgery, chemotherapy, radiation therapy, hormonal therapy, targeted therapy, and synthetic lethality. The targeted therapy refers to targeting only specific proteins or enzymes that are dysregulated in cancer rather than killing all rapidly dividing cells, has gained much attention in the recent past.

EtN/DMSO-supported one-pot synthesis of highly fluorescent β-carboline-linked benzothiophenones via sulfur insertion and estimation of the photophysical properties.

A robust transition-metal-free strategy is presented to access novel β-carboline-tethered benzothiophenone derivatives from 1(3)-formyl-β-carbolines using elemental sulfur activated by EtN/DMSO. This expeditious catalyst-free reaction proceeds through the formation of β-carboline-based 2-nitrochalcones followed by an incorporation of sulfur to generate multifunctional β-carboline-linked benzothiophenones in good to excellent yields. The synthetic strategy could also be extended towards the synthesis of β-carboline-linked benzothiophenes.

Isatin as a 2-aminobenzaldehyde surrogate: transition metal-free efficient synthesis of 2-(2'-aminophenyl)benzothiazole derivatives.

A transition metal-free, convenient, and efficient practical approach has been devised for the synthesis of substituted 2-(2'-aminophenyl)benzothiazoles via a sulfur insertion strategy using isatin derivatives as 2-aminobenzaldehyde surrogates. KI assisted one-pot operation of isatin, arylamines and elemental sulfur resulted in the formation of a C-N and two C-S bonds and cascade cleavage of the isatin ring resulting in the formation of 2-(2'-aminophenyl)benzothiazoles. The significant features of this strategy are the readily available and inexpensive starting materials, broad substrate scope, sustainable reaction conditions and high yield of products.

An AcOH-mediated metal free approach towards the synthesis of bis-carbolines and imidazopyridoindole derivatives and assessment of their photophysical properties.

An AcOH-mediated concise, atom-economical and environmentally sustainable tandem strategy has been formulated to access highly fluorescent (ΦF up to 40%) N-fused bis-carbolines, imidazopyrido[3,4-b]indoles and imidazo[1,5-a]pyridines via the formation of three C-N bonds in a single operation. The multicomponent character of the reaction, easy to execute reaction conditions, simple purification procedure and excellent light emitting properties of the product afforded thereof provide a huge scope.

Molecular Docking Studies on Isocytosine Analogues as Xanthine Oxidase Inhibitors.

Flexible docking simulations were carried out on a series of isocytosine analogs as xanthine oxidase (XO) inhibitors. This was done by analysing the interaction of these compounds at the active site of XO. The binding free energies of the analogs were calculated using GoldScore.

Natural product inspired design and synthesis of β-carboline and γ-lactone based molecular hybrids.

β-Carboline and γ-lactone moieties have been selected by nature as privileged scaffolds and display a wide range of pharmacological properties. Following nature, we envisaged the preparation of new β-carboline and γ-lactone based molecular hybrids incorporating both the pharmacophores. In this regard, a water-assisted In-mediated environmentally benign and easy to execute single-step tandem Barbier type allylation-lactonisation process has been devised in order to afford the targeted molecular architectures.