An efficient iodine-mediated oxidative annulation of aryl acetylenes-arylethenes-aromatic ketones with 1,2-diamines for the synthesis of pyrazines and regioselective synthesis of quinoxalines is presented. A multipathway coupled domino approach has been developed for the one-pot synthesis of 1,4-diazines with high functional group compatibility.

This paper reports the synthesis of nitrogen containing heterocyclic compounds such as quinoxalines (5-7), imidazoles (8, 9,10,11), aminothiazole (12), aminooxazole (13), aminoimidazole (14) and benzothiazine (17) from the reaction with unsymmetrical diketone 4, 3 and 4a respectively. The aforementioned compounds with 4-pyridyl,4fluorophenyl groups have different positions in their ring skeleto...

Diversity-oriented synthesis of novel benzimidazole linked indolo-benzodiazepine/quinoxaline ring systems using poly(ethylene glycol) as soluble polymer support is described. Commercially available 4-fluoro-3-nitrobenzoic acid and indoline were utilized for the construction of these annulated biheterocyclic compound libraries having multiple privileged structures with three-point structural div...

Abstract Heterocyclic amines (HCAs) are toxic products from the Maillard reaction that form of sugars, amino acids and creatine/creatinine when cooking protein rich food. In this work, commonly consumed meats in Saudi Arabia (camel, beef chicken) were fried under conditions resembling home cooking. The effect marinades made blueberry, raspberry strawberry tested separately on meat at different ...

An asymmetric transfer hydrogenation of 2,3-disubstituted quinoxalines using a chiral frustrated Lewis pair of Piers' borane and (R)-tert-butylsulfinamide as the catalyst with ammonia borane as the hydrogen source has been successfully realized. For 2-alkyl-3-arylquinoxaline substrates, cis-tetrahydroquinoxalines were obtained as the predominant products in high yields with 77-86% ee. In contra...

An efficient synthesis of trialkyl (E)-3-(3-Oxo-2-3,4-dihydro-2-(1H)-quinoxalinylidene)-prop-1-ene-1,2,3-tricarboxylate derivatives via a simple three-component reaction between benzene-1,2-diamines with dialkyl acetylenedicarboxylates in the presence of K2CO3-PEG catalytic system at 100 oC was reported. The desired products were obtained in excellent yields (88-92%). Various benzene-1,2-diamin...

A series of 1,3-disubstituted pyrrolo[2,3-b]quinoxalines has been designed for the potential inhibition of PDE4 without inhibiting luciferase. A ligand/PTC (phase transfer catalyst) free intramolecular Heck cyclization strategy was used to prepare these compounds, some of which showed significant inhibition of PDE4B (IC50≈ 5-14 μM) and growth inhibition of oral cancer cells (CAL 27) but not inh...