Letters in Organic Chemistry - Volume 21, Issue 11, 2024

The steroidal B-ring 2H-pyran 2 is synthesized by reacting steroidal B-ring α,β- unsaturated ketone 1 and 2-cyano-N-methylacetamide by refluxing for 18 h in methanol in the presence of a catalyst, i.e., chitosan. The product is obtained with a yield of 67%. The structure of the final product 2 is confirmed by utilizing IR, Mass, 13C and 1H NMR spectra. The reaction mechanism of the steroidal pyran ring formation is explored in th Read More

In addition to providing a succinct pathway for the stereoselective synthesis of dapoxetine, a potent SSRI employed in the treatment of premature ejaculation, this study highlights the strategic use of Ellman's sulfinamide as a chiral auxiliary. The key method involves the diastereoselective allylation of (S,E)-N-Benzylidenesulfinamide, resulting in the desired S-configuration critical for the pharmacological activity of dapoxetin Read More

An efficient synthesis of Chromeno[b]pyrimidine derivatives 4 has been achieved by treating 4-hydroxy-2H-chromen-2-one 1, furan-2-carbaldehyde / 1H-pyrrole-2-carbaldehyde/ thiophene-2- carbaldehyde 2, and urea/thiourea 3 at 65-70 °C for 90-120 min using 1-Ethyl-3-methylimidazolium acetate as ionic liquid and medium with good yields 86-90%. This synthetic method has numerous advantages, including high yields, a si Read More

The term isatin and its derivative-based MCRs have emerged over the years as a versatile, environment-friendly, and very promising platform for the construction of highly enabling bioactive organic scaffolds such as drugs, natural products, pharmaceuticals etc. In the world of recent advancements, the one-pot strategy based on isatin has come to the forefront of synthetic chemistry for the activation of small organic Read More

Fireballs are unusual and rare phenomena usually associated with thunderstorms, although sometimes they have been observed during earthquakes, volcano eruptions or in fair weather. There are still questions about their origination, features and interaction with the environment. In this work, a new model is shown to explain the formation of fireballs in fair weather from poplar cotton and peroxides produced by brow Read More

Our group recently reported that the polyhydroxy aromatic compound 3,3′,4,4′- biphenyltetrol (2a) is a successful inhibitor of amyloid-β peptide (Aβ) aggregation, decreasing Aβ aggregation by 50 % when present in equimolar concentrations. In the present study, several additional biphenyltetrols were prepared and examined for their in vitro activity against aggregation of Aβ to investigate the effect of the relative p Read More

Novel hydrazones 4, 5, and oxime 6 were produced from the reaction of ketone 3 with hydrazine, phenylhydrazine, and hydroxylamine HCl, respectively. One pot multicomponent reaction of chalcones 7a-c, 3-(1H-indol-3-yl)-3-oxopropanenitrile 8, and ammonium acetate in MeOH at reflux temperature gave 2-(1H-indol-3-yl)-nicotinonitrile derivatives 10-12. Additionally, a one-pot reaction of chalcone 7a, malononitrile Read More

The electron properties of baicalein-family are of great importance in influencing its properties and corresponding bioactivities. In this work, we conducted comprehensive quantum chemistry calculations on pristine baicalein, and its two hydroxyl-substituted derivatives where the hydroxylsubstitution respectively occur at A and C rings. By contrasting with each other, the effects of the hydroxyl-substitution on the el Read More