Electrochemical formal homocoupling of sec-alcohols

Electrochemical pinacol coupling of carbonyl compounds in an undivided cell with a sacrificial anode would be a promising approach toward synthetically valuable vic-1,2-diol scaffolds without using low-valent metal reductants. However, sacrificial anodes produce an equimolar amount of metal waste, which may be a major issue in terms of sustainable chemistry. Herein, we report a sacrificial anode-free electrochemical protocol for the synthesis of pinacol-type vic-1,2-diols from sec-alcohols, namely benzyl alcohol derivatives and ethyl lactate. The corresponding vic-1,2-diols are obtained in moderate to good yields, and good to high levels of stereoselectivity are observed for sec-benzyl alcohol derivatives. The present transformations smoothly proceed in a simple undivided cell under constant current conditions without the use of external chemical oxidants/reductants, and transition-metal catalysts.

Copper-Catalyzed Enantioselective Oxysulfenylation of Alkenols: Synthesis of Arylthiomethyl-Substituted Cyclic Ethers

Saturated heterocycles containing oxygen and sulfur are found in biologically significant molecules. The enantioselective oxysulfenylation of alkenols provides a straightforward synthesis route. To date, organocatalytic methods have dominated this approach. Herein, a complementary approach via copper catalysis is presented. This exoselective method provides enantioenriched arylthiomethyl-substituted tetrahydrofurans, phthalans, isochromans, and morpholines from acyclic alkenols. This method provides the largest scope to date for the exocyclization mode, and with generally high enantioselectivity. The enantioselectivity of this copper-catalyzed oxysulfenylation is rationalized by a proposed mechanism involving alkene oxycupration followed by C─S bond formation via radical-mediated atom transfer.

Molecular docking analysis of curcumin analogues with COX-2

Curcumin analogues were evaluated for COX-2 inhibitory as anti-inflammatory activities. The designed analogues significantly enhance COX-2 selectivity. The three compounds could dock into the active site of COX-2 successfully. The binding energies of -8.2, - 7.6 and -7.5 kcal/mol were obtained for three analogues of curcumin respectively. Molecular docking study revealed the binding orientations of curcumin analogues in the active sites of COX-2 towards the design of potent inhibitors.

Synthesis, biological evaluation, docking study and ulcerogenicity profiling of some novel quinoline-2-carboxamides as dual COXs/LOX inhibitors endowed with anti-inflammatory activity

A series of novel quinoline-2-carboxamides 15-28 was synthesized and evaluated in vitro as dual COXs/LOX inhibitors. Compounds 19 and 27 exhibited the highest potency and selectivity for COX-2 inhibitory activity (IC₅₀ = 1.21 and 1.13 μM, respectively; selectivity index (COX-1/COX-2) = 6.52 and 7.61, respectively) in comparison to the reference drug celecoxib (COX-2 IC₅₀ = 0.88 μM; selectivity index (COX-1/COX-2) = 8.31). The anti-inflammatory activity of the newly synthesized compounds was further assessed in vivo using carrageenan induced paw edema assay. Interestingly, the in vitro results of COXs inhibitory assay were consistent with that of the in vivo assay where compounds 19 and 27 showed the highest anti-inflammatory activity with edema inhibition percentages of 59.38% and 65.03%, respectively compared to celecoxib (71.21%) after 5 h. Moreover, it was found that compounds 19 and 27 have a superior gastric safety profile comparable to indomethacin. The molecular docking study of compounds 19 and 27 into COX-2 active site suggested that these hits assumed binding pattern and interactions similar to that of bromocelecoxib (S-58) as a cocrystallized ligand explaining their remarkable COX-2 inhibitory activity and selectivity. Taken together, these results indicated that these derivatives are good leads for subsequent development into potential anti-inflammatory agents with least gastric damage.