Visible-Light-Induced Singlet Oxygen-Promoted Arylation and Alkylation of Quinoxalin-2(1H)-ones and Quinolines.

We report a green and efficient visible-light-driven method for the arylation and alkylation of quinoxalin-2(1H)-ones and quinolines. This catalyst-free process utilizes air as the oxidant, offering mild reaction conditions, environmental sustainability, and broad functional group compatibility. The approach enables the synthesis of aryl and alkyl derivatives of quinoxalin-2(1H)-ones and quinolines with high to excellent yields.

Discovery of a novel highly potent and low-toxic jatrophane derivative enhancing the P-glycoprotein-mediated doxorubicin sensitivity of MCF-7/ADR cells.

Use of novel modulators targeting P-glycoprotein (P-gp, ABCB1 transporter) is among the most accepted strategies for overcoming multidrug resistance in cancer chemotherapy. In the current study, we pursued our structure-activity relationship studies of jatrophane derivatives by structural modification of compound 1, a natural jatrophane isolated from Euphorbia. sororia A.

Jatrophane diterpenoids from Euphorbia microcarpa (prokh.) krylov with multidrug resistance modulating activity.

Eight undescribed jatrophane diterpenoids, namely euphomicrophane A-H, together with thirteen known diterpenes were isolated from the whole plant extracts of Euphorbia microcarpa (Prokh.) Krylov. Among them, euphomicrophane C and F were possessed the endo-type core structure that naturally rarely appeared.

Diterpenoids from Euphorbia glomerulans with potential reversal activities against P-glycoprotein-mediated multidrug resistance.

The development of collateral sensitivity agents that are able to modulate P-glycoprotein (P-gp) is the most promising approaches to overcome multidrug resistance (MDR) in cancer. In this study, eight new diterpenoids of jatrophane and ingenane type, 1-8, and three known ones (9-11) were isolated from Euphorbia glomerulans. Their structures were elucidated by spectroscopic analysis and electronic circular dichroism (ECD) calculations.

Jatrophane diterpenoids as multidrug resistance modulators from Euphorbia sororia.

Eight new jatrophane diterpenoids, Euphosorophane F-M (1-8), as well as fourteen known jatrophane diterpenoids (9-22) were separated and purified from the fructus of Euphorbia sororia, and the chemical structures were determined based on extensive spectroscopic analysis, 1D, 2D NMR and HRESIMS data included. Their absolute configurations of compounds 1, 2, 9, and 22 were elucidated by X-ray crystallographic analysis. These jatrophane diterpenoids showed lower cytotoxicity and compounds 3, 4, 11, 12, 13, 14, and 20 revealed promising multidrug resistance (MDR) reversal ability as modulators compared to verapamil (VRP) by MTT assay.

Crystal and mol-ecular structure of jatrophane diterpenoid (2,3,4,5,7,8,9,13,14,15)-2,3,8,9-tetra-acet-oxy-5,14-bis-(benzo-yloxy)-15-hydroxy-7-(iso-butano-yloxy)jatropha-6(17),11()-diene.

The structure of the jatrophane diterpenoid (ES2), CHO, has ortho-rhom-bic (222) symmetry. The absolute configuration in the crystal has been determined as 2,3,4,5,7,8,9,13,14,15 [the Flack parameter is -0.06 (11)].

Ancient Chemistry "Pharaoh's Snakes" for Efficient Fe-/N-Doped Carbon Electrocatalysts.

The method of fabricating nonprecious metal electrocatalysts with high activity and durability through a facile and eco-friendly procedure is of great significance to the development of low-cost fuel cells and metal-air batteries. Herein, we present that an ancient chemical reaction of "Pharaoh's snakes" can be a fast and convenient technique to prepare Fe-/N-doped carbon (Fe/N-C) nanosheet/nanotube electrocatalysts with sugar, soda, melamine, and iron nitrate as precursors. The resultant Fe/N-C catalyst has a hierarchically porous structure, a large surface area, and uniformly distributed active sites.