Formal [4 + 2] combined ionic and radical approach of vinylogous enaminonitriles to access highly substituted sulfonyl pyridazines.

Pyridazine derivatives hold significant interest due to their broad applications in pharmaceuticals and materials science, where they serve as valuable scaffolds for bioactive compounds and functional materials. Here, we report a formal [4 + 2] reaction for the synthesis of 5'-sulfonyl-4'-aryl-3-cyano substituted pyridazine compounds from the reaction between vinylogous enaminonitriles and sulfonyl hydrazides. The key features of our pyridazine synthesis include the transamidation of vinylogous enaminonitriles with sulfonyl hydrazide, radical sulfonylation of the resulting intermediate, and subsequent 6-endo-trig radical cyclization.

Reagent-Free Intramolecular Hydroamination of Ynone-Tethered Aryl-sulfonamide: Synthesis of Polysubstituted 4-Quinolones.

An efficient reagent-free method for the synthesis of polysubstituted 4-quinolone from 2-substituted alkynoyl aryl-sulfonamide was developed. This developed method tolerates various functional groups and gives the corresponding 4-quinolones. We have successfully extended this method to the synthesis of dihydro-4-quinolones from 2-alkenoyl aryl sulfonamide derivatives.

Microwave-Mediated, Catalyst-Free Synthesis of 1,2,4-Triazolo[1,5-]pyridines from Enaminonitriles.

A catalyst-free, additive-free, and eco-friendly method for synthesizing 1,2,4-triazolo[1,5-]pyridines under microwave conditions has been established. This tandem reaction involves the use of enaminonitriles and benzohydrazides, a transamidation mechanism followed by nucleophilic addition with nitrile, and subsequent condensation to yield the target compound in a short reaction time. The methodology demonstrates a broad substrate scope and good functional group tolerance, resulting in the formation of products in good-to-excellent yields.

Total Synthesis of Isohericerinol A and Its Analogues to Access Their Potential Neurotrophic Effects.

The secondary metabolites from are well-known to have neurotrophic and neuroprotective effects. Isohericerinol A (), isolated by our colleagues from its fruiting parts has a strong ability to increase the nerve growth factor secretion in C6 glioma cells. The current work describes the total synthesis of and its regioisomer in a few steps.

α-Hydroxy acid as an aldehyde surrogate: metal-free synthesis of pyrrolo[1,2-]quinoxalines, quinazolinones, and other N-heterocycles decarboxylative oxidative annulation reaction.

A metal-free and efficient procedure for the synthesis of pyrrolo[1,2-]quinoxalines, quinazolinones, and indolo[1,2-]quinoxaline has been developed. The key features of our method include the generation of aldehyde from α-hydroxy acid in the presence of TBHP (-butyl hydrogen peroxide), and further condensation with various amines, followed by intramolecular cyclization and subsequent oxidation to afford the corresponding quinoxalines, quinazolinones derivatives in moderate to high yields.

Hematite/M (M = Au, Pd) Catalysts Derived from a Double-Hollow Prussian Blue Microstructure: Simultaneous Catalytic Reduction of - and -Nitrophenols.

Present study deals with hematite/M (M = Au, Pd) catalysts converted from a double-hollow Prussian blue microstructure (DHPM). The unique Prussian blue (PB) microstructure (MS) is prepared by a template-free solvothermal synthetic route in a single-step reaction. An amine-functionalized silicate sol-gel matrix (SSG) has served as the structure-directing agent cum stabilizer for making DHPM.

Transition metal-free synthesis of quinazolinones using dimethyl sulfoxide as a synthon.

Biologically important quinazolinones have been synthesized from 2-aminobenzamides and DMSO. The key feature of the reaction is the utilization of DMSO as a methine source for intramolecular oxidative annulation. The CNS depressant drug methaqualone has also been synthesized by our methodology.

Synthesis, biological evaluation, and metabolic stability of chlorogenic acid derivatives possessing thiazole as potent inhibitors of α-MSH-stimulated melanogenesis.

A series of catechol and dioxolane analogs containing thiazole CGA derivatives have been synthesized and evaluated for their inhibitory activity against α-MSH. The inhibitory activity was improved by replacing an α,β-unsaturated carbonyl of previously reported caffeamides with thiazole motif. Surprisingly, compound 7d, one of the derivatives of dioxolane analogs, displayed the most potent inhibitory activity with an IC of 0.

Synthesis and biological evaluation of caffeic acid derivatives as potent inhibitors of α-MSH-stimulated melanogenesis.

We have disclosed our effort to develop caffeic acid derivatives as potent and non-toxic inhibitors of α-MSH-stimulated melanogenesis to treat pigmentation disorders and skin medication including a cosmetic skin-whitening agent. The SAR studies revealed that cyclohexyl ester and secondary amide derivatives of caffeic acid showed significant inhibitory activities.

Concise Synthesis of Broussonone A.

A concise and expeditious approach to the total synthesis of broussonone A, a p-quinol natural compound, has been developed. The key features of the synthesis include the Grubbs II catalyst mediated cross metathesis of two aromatic subunits, and a chemoselective oxidative dearomatizationin the presence of two phenol moieties. Especially, optimization associated with the CM reaction of ortho-alkoxystyrenes was also studied, which are known to be ineffective for Ru-catalyzed metathesis reactions under conventional reaction conditions because ortho-alkoxy group could coordinate to the ruthenium center, resulting in the potential complication of catalyst inhibition.