33821-28-2Relevant academic research and scientific papers
Chemical- vs sonochemical-assisted synthesis of ZnO nanoparticles from a new zinc complex for improvement of carotene biosynthesis from Rhodotorula toruloides MH023518
Ibrahim, Ahmed B.M.,Mahmoud, Ghada Abd-Elmonsef
, (2021)
The complex [ZnL2] {HL = 2-(((3,4-dimethylphenyl)imino)methyl)phenol} was introduced by two routes (chemical vs. sonochemical) and acted as a source of different size zinc-oxide (ZnO) nanoparticles (NPs) (nonsonicated ZnO NPs of Brunauer–Emmett–Teller (BET) surface area of 19.208 m2 g?1, total pore volume of 0.03493 cc g?1, and particle diameter of 20.49–114.89 nm vs. sonicated ZnO NPs of BET surface area of 38.383 m2 g?1, total pore volume of 0.08723 cc g?1 and particle diameter of 15.09–55.31 nm). The NPs generate cell stress that leads to the formation of reactive oxygen species (ROS). Consequently, carotene biosynthesis can be enhanced to overcome the ROS. Rhodotorula toruloides MH023518, genetically identified with 18S rRNA, produced carotenoids (124 ± 4.5 mg L?1) and lipids (0.897 ± 0.01 mg L?1) under no NPs' stress, but these values increased to total carotenoids of 264 ± 0.6 and 297.78 ± 0.8 mg L?1 and total lipids of 0.97 ± 0.007 and 1.096 ± 0.015 mg L?1 under stress conditions of 50 ppm of the nonsonicated and sonicated ZnO NPs, respectively. These results may represent potential industrial utilization of the as-formed ZnO NPs (particularly the sonicated sample) as carotene and lipid stimulator. Additionally in this article, the soluble proteins, total antioxidants, and catalase and superoxide dismutase specific activities of the yeast in the presence of various concentrations of the as-formed ZnO NPs were determined.
Copper-Catalyzed Asymmetric Annulation Reactions of Carbenes with 2-Iminyl- or 2-Acyl-Substituted Phenols: Convenient Access to Enantioenriched 2,3-Dihydrobenzofurans
Liang, Xin-Shen,Li, Rui-Dong,Wang, Xiao-Chen
supporting information, p. 13885 - 13889 (2019/08/26)
We have developed a method for the highly diastereo- and enantioselective construction of 2,3-dihydrobenzofurans bearing tetrasubstituted carbon stereocenters by means of annulation reactions between carbenes and 2-iminyl- or 2-acyl-substituted phenols through catalysis by readily accessible copper(I)/bisoxazoline catalysts under mild conditions. These reactions feature a unique mechanism in which the copper catalyst serves a dual function: first it reacts with the diazo compound to generate a metal carbene, and second, upon formation of an oxonium ylide, it acts as a Lewis acid to activate the imine or ketone for diastereo- and enantioselective cyclization.
