Results 51 to 60 of about 511,953 (205)

To Greater Twist: A Kinetically Biased π‐Radical Cascade

Angewandte Chemie, EarlyView.
π‐Radical cascades enable step‐economic construction of complex polycyclic aromatic frameworks. In this work, we show that a multifurcating pathway can be kinetically steered toward a single, more distorted product. This counterintuitive “falling‐upward” outcome arises from an intrinsic mechanistic bias, revealing a broader dimension of control in π ...
Yong Yang, Joshua C. Walsh, Li Sun, Kevin A. Quintanilla, Ignacio A. Rivas, Zheng Zhou, Juan Casado, Carlos M. Cruz, Michal Juríček   +8 more
wiley   +2 more sources

Dual Nickel/Photoredox‐Catalyzed Regio‐ and Enantioselective Alkenylation of Epoxides

Advanced Science, EarlyView.
Ni/photoredox‐catalyzed stereoconvergent cross‐electrophile coupling of racemic epoxides with alkenyl bromides is described, affording β‐alkenyl products with up to 95% ee, excellent E‐selectivity, and complete regiocontrol. These versatile intermediates enable diverse chiral synthons; mechanistic studies suggest a halide ring‐opening followed by ...
Hongyan Lan, Shengzhou Jin, Zhao‐Dong Xu, Guigen Li, Dingyi Wang   +4 more
wiley   +1 more source

Photometallobiocatalytic Asymmetric Radical‐Mediated Cross‐Coupling of Organotrifluoroborate Salts and Pyridotriazoles

Angewandte Chemie, EarlyView.
An enantioselective photometallobiocatalytic cross‐coupling of pyridotriazoles and secondary alkyltrifluoroborate salts is developed. Cooperative catalysis using eosin B and an engineered protoglobin combines visible‐light‐mediated radical generation with enzymatic metal carbenoid activation, affording valuable N‐heterocyclic products in excellent ...
Huanan Wang, Binh Khanh Mai, Xingjie Zhang, Chongtao Li, Peng Liu, Yang Yang   +5 more
wiley   +2 more sources

Stability toward High Energy Radiation of Non-Proteinogenic Amino Acids: Implications for the Origins of Life

Life, 2013
A series of non-proteinogenic amino acids, most of them found quite commonly in the meteorites known as carbonaceous chondrites, were subjected to solid state radiolysis in vacuum to a total radiation dose of 3.2 MGy corresponding to 23% of the total ...
Yaser Hafez, Giancarlo Angelini, Franco Cataldo, Susana Iglesias-Groth   +3 more
doaj   +1 more source

Redox-enabled direct stereoconvergent heteroarylation of simple alcohols

Nature Communications, 2021
Synthesizing complex structures of high enantiomeric excess from racemic feedstock is an enduring challenge. Here, the authors couple racemic secondary alcohols with pyrroles to form enantioenriched 2-substituted heteroarenes, via a borrowing hydrogen ...
Yongbing Liu, Ran Tao, Zhi-Keng Lin, Guoqiang Yang, Yu Zhao   +4 more
doaj   +1 more source

Supramolecular Chiral Assemblies from Benzoselenadiazole‐Alanine‐Acylhydrazone Conjugates Enable Cardioprotection

Advanced Science, EarlyView.
The C3‐symmetric conjugate TASe, which integrates benzoselenadiazole, alanine, and acylhydrazone modules, self‐assembles into a chalcogen‐/hydrogen‐bonded porous framework in the solid state and uniform chiral nanospheres in aqueous media. These assemblies protect cardiomyocytes from doxorubicin‐induced oxidative injury by scavenging intracellular ...
Jinkui Teng, Renjing Yang, Yu Du, Jingzhong Duan, Yiming Xu, Zhihua He, Guanghui Wang, Wenjing Tian, Aijie Liu, Haifeng Chen, Yun‐Bao Jiang, Xiaosheng Yan   +11 more
wiley   +1 more source

An X‑Shaped Chiral Non‑Fullerene n‐Type Semiconductor: Application in Perovskite Solar Cells and Chirality‑Induced Spin Selectivity

Angewandte Chemie, EarlyView.
A highly electron‑accepting derivative of cyclobisbiphenylenecarbonyl (CBBC‐TIC) is reported. CBBC‐TIC functions as an electron‐transport layer for perovskite solar cells, achieving a power conversion efficiency of 20.6%. Furthermore, the enantiomers of CBBC‐TIC exhibited spin‐selective electron transport with high enantiospecific magnetic conductance ...
Yuki Sakamoto, Koki Otsuka, Kuraudo Ishihara, Shuang Li, Ai Shimazaki, Megumi Haramatsu, Junichiro Hirano, Juntaro Nogami, Hiroshi Shinokubo, Hiroki Uratani, Hironori Kaji, Fumitaka Ishiwari, Akinori Saeki, Tomoya Nakamura, Atsushi Wakamiya, Norihito Fukui   +15 more
wiley   +2 more sources

Chiral symmetry breaking and information accumulation in pre-biological protocell evolution

Scientific Reports
We study a linear evolutionary model based on the two-dimensional distribution of protocells by total enantiomeric excess and the amount of stored information, which they can pass from generation to generation, and without any mutual inhibition.
Konstantin K. Konstantinov, Alisa F. Konstantinova   +1 more
doaj   +1 more source

Novel Chiral Switching Ligands for Enantioselective Asymmetric Reductions of Prochiral Ketones

Molecules, 2001
The newly developed chiral ligands 1 and 4 show opposite enantioselectivity in the asymmetric reduction of prochiral ketones resulting in the production of either enantiomer depending on the metal complex with high enantiomeric excess.
S. Velmathi, R. Balakumar, S. Swarnalakshmi, S. Narasimhan   +3 more
doaj   +1 more source

Highly Efficient Lipase-Catalyzed Kinetic Resolution of Chiral Amines

CHIMIA, 1994
The lipase Candida antarctica catalyzes the enantioselective acetylation of chiral primary amines, kinetic resolution leading to an enantiomeric excess (ee) of 90–98%.
Manfred T. Reetz, Claus Dreisbach
doaj   +2 more sources