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This document provides a summary of various methods for the synthesis of tetrasubstituted axially chiral alkenes. The methods discussed include urea group-directed organocatalytic dihalogenation, Rh(III)-catalyzed C-H activation and directing group migration, cationic rhodium(I)/H8-BINAP-catalyzed chelation-controlled cycloaddition, Cu/Pd dual catalysis for arylboration, nickel-catalyzed cross-electrophile trans-aryl-benzylation, palladium-catalyzed C-H functionalization, Pd(II)-catalyzed thioether-directed alkenyl C-H olefination, Suzuki-Miyaura cross-coupling, asymmetric N-alkylation, chiral phosphoric acid catalyzed kinetic resolution, and asymmetric allylic substitution-isomerization. The methods demonstrate broad substrate scope and high enantioselectivities, but further research is needed to explore stereodivergent synthesis and applications in pharmaceutical chemistry. [Extracted from the article]

In this study, the form factors of B (s) to light D-wave tensor mesons with J PC = 2 - - ( ρ 2 , ω 2 , K 2 and ϕ 2 ) are calculated via the light cone sum rules (LCSR) in the framework of heavy quark effective eld theory (HQEFT). Firstly, the expressions of form factors in terms of the light cone distribution amplitudes (LCDAs) of tensor mesons are derived via the LCSR at the leading order of heavy quark expansion. Similar to the case of 2 + + tensor mesons, the penguin type form factors can be obtained directly from the corresponding semileptonic ones. Considering the light tensor meson LCDAs to twist-3 and quark mass corrections, we give the numerical results of form factors systematically. Based on the form factors given here, we investigate the branching ratios, longitudinal polarization fractions and forward-backward asymmetries of relevant charged current induced semileptonic decays. Our results may be tested by more precise experiments in the future. [ABSTRACT FROM AUTHOR]

Axially chiral N‐substituted quinazolinones are important bioactive molecules, which are presented in many synthetic drugs. However, most strategies toward their atroposelective synthesis are mainly limited to the axially chiral arylquinazolinone frameworks. The development of modular synthetic methods to access diverse quinazolinone‐based atropisomers remains scarce and challenging. Herein, we report the regio‐ and atroposelective synthesis of axially chiral N‐vinylquinazolinones via the strategy of asymmetric allylic substitution‐isomerization. The catalysis system utilized both asymmetric transition‐metal catalysis and organocatalysis to efficiently afford trisubstituted and tetrasubstituted N‐vinylquinazolinone atropisomers, respectively. With the meticulous design of β‐substituted allylic substrates, both Z‐ and E‐tetrasubstituted axially chiral N‐vinylquinazolinones were obtained in good yields and high enantioselectivities. [ABSTRACT FROM AUTHOR]

A simple Pd/Cu-catalyzed borylation of allenylic carbonates with B2Pin2 was developed using a cheap P(OEt)3 ligand. Under mild neutral conditions, 2-boryl 1,3-butadienes were obtained selectively in moderate to high yields. Furthermore, the use of different diboron reagents was also feasible in the reaction. [ABSTRACT FROM AUTHOR]

Cancer stands as a prominent global cause of death. One of the key reasons why clinical tumor chemotherapy fails is multidrug resistance (MDR). In recent decades, accumulated studies have shown how Natural Product-Derived Compounds can reverse tumor MDR. Discovering novel potential modulators to reduce tumor MDR by Natural Product-Derived Compounds has become a popular research area across the globe. Numerous studies mainly focus on natural products including flavonoids, alkaloids, terpenoids, polyphenols and coumarins for their MDR modulatory activity. Natural products reverse MDR by regulating signaling pathways or the relevant expressed protein or gene. Here we perform a deep review of the previous achievements, recent advances in the development of natural products as a treatment for MDR. This review aims to provide some insights for the study of multidrug resistance of natural products., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zou, Chen, Luo, Damdinjav, Abdelmohsen, Li, Battulga, Chen, Wang and Zhang.)