Mechanism and origin of enantioselectivity for organocatalyzed asymmetric heteroannulation of alkynes in the construction of axially chiral C2-arylquinoline.

Axially chiral C2-arylquinoline has been successfully constructed via asymmetric heteroannulation of alkynes catalyzed by chiral phosphoric acid with high yield and high enantioselectivity. Inspired by this intriguing work, theoretical calculations have been carried out, and the detailed reaction mechanism has been elaborated, in which the whole reaction can be divided into steps including hydrogen transfer, C-N bonding, annulation reaction and the final dehydration processes. The initial hydrogen-transfer reaction has two possible pathways, while the subsequent C-N bonding process has eight possible pathways. Then, after the annulation reaction and the final dehydration processes, the major product and byproduct were formed. QTAIM and IGMH analyses were used to illustrate the role of weak intermolecular interactions in the catalytic process, and the distortion/interaction and EDA analyses provided a deeper understanding of the origin of enantioselectivity. The calculated results are consistent with the experimental results. This work would provide valuable insights into asymmetric reactions catalyzed by chiral phosphoric acid.

Mapping of dwarfing QTL of Ari1327, a semi-dwarf mutant of upland cotton.

BACKGROUND: Upland Cotton (Gossypium hirsutum L.) has few cotton varieties suitable for mechanical harvesting. The plant height of the cultivar is one of the key features that need to modify. Hence, this study was planned to locate the QTL for plant height in a 60Co γ treated upland cotton semi-dwarf mutant Ari1327. RESULTS: Interestingly, bulk segregant analysis (BSA) and genotyping by sequencing (GBS) methods exhibited that candidate QTL was co-located in the region of 5.80-9.66 Mb at D01 chromosome in two F2 populations. Using three InDel markers to genotype a population of 1241 individuals confirmed that the offspring's phenotype is consistent with the genotype. Comparative analysis of RNA-seq between the mutant and wild variety exhibited that Gh_D01G0592 was identified as the source of dwarfness from 200 genes. In addition, it was also revealed that the appropriate use of partial separation markers in QTL mapping can escalate linkage information. CONCLUSIONS: Overwhelmingly, the results will provide the basis to reveal the function of candidate genes and the utilization of excellent dwarf genetic resources in the future.

ß-Caryophyllene Acts as a Ferroptosis Inhibitor to Ameliorate Experimental Colitis.

Macrophage infiltration is one of the main pathological features of ulcerative colitis (UC) and ferroptosis is a type of nonapoptotic cell death, connecting oxidative stress and inflammation. However, whether ferroptosis occurs in the colon macrophages of UC mice and whether targeting macrophage ferroptosis is an effective approach for UC treatment remain unclear. The present study revealed that macrophage lipid peroxidation was observed in the colon of UC mice. Subsequently, we screened several main components of essential oil from Artemisia argyi and found that ß-caryophyllene (BCP) had a good inhibitory effect on macrophage lipid peroxidation. Additionally, ferroptotic macrophages were found to increase the mRNA expression of tumor necrosis factor alpha (Tnf-α) and prostaglandin-endoperoxide synthase 2 (Ptgs2), while BCP can reverse the effects of inflammation activated by ferroptosis. Further molecular mechanism studies revealed that BCP activated the type 2 cannabinoid receptor (CB2R) to inhibit macrophage ferroptosis and its induced inflammatory response both in vivo and in vitro. Taken together, BCP potentially ameliorated experimental colitis inflammation by inhibiting macrophage ferroptosis. These results revealed that macrophage ferroptosis is a potential therapeutic target for UC and identified a novel mechanism of BCP in ameliorating experimental colitis.