Microwave-Assisted Convenient Synthesis ofα,β-Unsaturated Esters and KetonesviaAldol-Adduct Elimination

A Review on Biological Properties and Synthetic Methodologies of Diarylpentadienones

Medicinal chemists have continuously shown interest in new curcuminoid derivatives, diarylpentadienones, owing to their enhanced stability feature and easy preparation using a one-pot synthesis. Thus far, methods such as Claisen-Schmidt condensation and Julia- Kocienski olefination have been utilised for the synthesis of these compounds. Diarylpentadienones possess a high potential as a chemical source for designing and developing new and effective drugs for the treatment of diseases, including inflammation, cancer, and malaria. In brief, this review article focuses on the broad pharmacological applications and the summary of the structure-activity relationship of molecules, which can be employed to further explore the structure of diarylpentadienone. The current methodological developments towards the synthesis of diarylpentadienones are also discussed.

α,β-Disubstituted CF3-Enones as a Trifluoromethyl Building Block: Regioselective Preparation of Totally Substituted 3-CF3-Pyrazoles

An efficient pathway toward a novel class of trifluoromethyl building blocks was elaborated. The reaction of α-CF₃-enamines with arylaldehydes resulted in direct synthesis of α,β-diaryl-CF₃-enones isolated in up to 93% yield as E-isomers. The possible reaction mechanism was proposed using the Zimmerman-Traxler model. The reaction of α,β-diaryl-CF₃-enones with hydrazines opens a novel pathway to trifluoromethylated pyrazolines. Oxidation of pyrazolines with DDQ opened access to totally regioselective preparation of 3-CF₃-pyrazoles isolated in high yield. Using this strategy, 4-arylated derivatives of known drugs Celebrex, Mavacoxib, and SC-560 can be synthesized.

Facile construction of novel heterocyclic compounds: three-component, one-pot synthesis of 2-hydroxybenzoyl-1,2-dihydropyridine-3-carboxylates, ketones, pyridone-3-carboxylates and benzopyrido-1,3-oxazole-4-carboxylates

A facile method has been developed for the preparation of novel heterocyclic compounds facilitated by 3-oxobutanoates and 1,3-diketones possessing a trihalo group. This three-component, one-pot protocol provided heterocyclic compounds without a catalyst.