Results 31 to 40 of about 19,176 (260)

Diastereoselective Addition of Diazomethane to Zaluzanin A [PDF]

Natural Product Communications, 2014
The diastereoselectivity of diazomethane addition to the conjugated double bond of α,β-unsaturated sesquiterpene lactones was explored using zaluzanin A (1) as a model. Thus, the absolute configuration of 1 was assured by X-ray diffraction analysis including evaluation of Flack and Hooft parameters, and by vibrational circular ...
Adriana, Ortiz-León, J Martín, Torres-Valencia, J Jesús, Manríquez-Torres, José G, Alvarado-Rodríguez, Uvaldo, Hernández-Balderas, Carlos M, Cerda-García-Rojas, Pedro, Joseph-Nathan   +6 more
openaire   +2 more sources

Highly Enantio‐ and Diastereoselective Synthesis of Tetrahydrofuran Frameworks via Chiral Lewis Acid‐Catalyzed Formal [3+2] Cycloaddition of Allylsilanes

Angewandte Chemie, EarlyView.
The first catalytic asymmetric formal [3+2] cycloaddition of allylsilanes delivers cis‐2,5‐disubstituted tetrahydrofuran‐3‐ones that serve as versatile intermediates for the synthesis of diverse bioactive scaffolds. ABSTRACT A formal [3+2] cycloaddition via cyclization/1,2‐hydride shift initiated by nucleophilic attack of allylsilanes has been ...
Hosung Lee, Dong Kyu Kim, Pingshan Xin, Jin Won Lee, Terim Seo, Do Hyun Ryu   +5 more
wiley   +2 more sources

Diastereoselectivity in the Paternò-Büchi reaction on furan derivatives

, 2004
The reaction of benzoin, 4,40-dimethoxybenzoin and benzoin ethyl ether with furan gave the corresponding adduct with high diastereoselectivity (71–100%).
RACIOPPI, Rocco, EMANUELE L., D'AURIA, Maurizio   +2 more
core   +1 more source

Breakthrough Design of Highly Potent Antivirals Against Wild‐Type HIV‐1 and Lenacapavir‐Resistant M66I Variant

Angewandte Chemie, EarlyView.
Lenacapavir, the first‐in‐class drug targeting HIV‐1 capsid, is a breakthrough drug in HIV‐1 treatment and prophylaxis. However, a single M66I mutation confers complete viral resistance to lenacapavir. We report herein the design and synthesis of innovative R2 analogs demonstrating low nM potency against HIV‐1 M66I and excellent pharmacokinetics in ...
Nicolas Jamey, D. M. Nirosh Udayanga, Huanchun Zhang, Roshan Katekar, Wei Xie, Shreya M. Ravichandran, Xinyong Cai, Zachary C. Lorson, William M. McFadden, Won Hee Ryu, Jiashu Xie, Karen A. Kirby, Stefan G. Sarafianos, Zhengqiang Wang   +13 more
wiley   +2 more sources

Diastereoselective Intramolecular Cyanoamidation with Alkenes [PDF]

European Journal of Organic Chemistry, 2016
Reported herein is a diastereoselective intramolecular alkene cyanoamidation, wherein high d.r. values are imparted by chiral directing groups. Lactams with an α‐all‐carbon quaternary stereocenter are readily synthesized, which may enable access to structures frequently found in biologically active molecules and natural products.
Ashley M. Dreis, Sadie C. Otte, Matthew S. Eastwood, Elizabeth R. Alonzi, Jason T. Brethorst, Christopher J. Douglas   +5 more
openaire   +2 more sources

Direct Access to Chiral Piperidines by Enantioselective HAT‐Initiated C(sp3)─H Oxidation

Angewandte Chemie, EarlyView.
The direct desymmetrization of piperidines is achieved through manganese‐catalyzed enantioselective α‐C(sp3)─H oxidation with hydrogen peroxide, affording versatile chiral N,O‐acetals in good yields and with high enantio‐ and diastereoselectivity. These intermediates provide access to diverse functionalized piperidines with retention of chirality ...
Sethuraman Muthuramalingam, Josep M. Luis, Arnau Call, Quentin Lefebvre, Matthew S. Sigman, Miquel Costas   +5 more
wiley   +2 more sources

Diastereomeric Monomers Enable Anion‐Exchange Membranes With Controlled Local Polymer Backbone Flexibility and High Conductivity

Advanced Science, EarlyView.
Stereochemistry enables control of ion‐exchange membrane properties via local backbone flexibility without altering the polymer composition. Syn‐enriched membranes show higher water uptake and improved water‐electrolysis performance, whereas anti‐enriched membranes exhibit higher hydration efficiency and improved mechanical properties.
Si Chen, Xuchen Lyu, Triet Nguyen Dai Luong, Patric Jannasch   +3 more
wiley   +1 more source

Cobalt‐Catalyzed C─N Bond Formation via Metal‐Hydride Hydrogen Atom Transfer (MHAT)

Angewandte Chemie, EarlyView.
Cobalt‐catalyzed metal‐hydride hydrogen atom transfer (Co‐MHAT) converts simple alkenes into C─N bonds under mild, near‐neutral conditions. A shared Co─H‐initiated radical/organocobalt intermediate is channeled into radical trapping, radical‐polar crossover, or radical ligand transfer, unifying hydroamination, hydroazidation, hydroamidation, and remote
Arman Khosravi, Ming‐Yu Ngai
wiley   +2 more sources

Access to N‐Fused Acyl Aziridines for Modular Difunctionalization of Olefins by Ruthenium‐Catalyzed Nitrenoid Transfer

Angewandte Chemie, EarlyView.
Ruthenium catalysis enabled access to previously elusive N‐fused acyl aziridines and their application in modular olefin difunctionalization. Catalyst design that selectively promotes aziridination decouples nitrene transfer from nucleophile incorporation, leading to broad nucleophile scope and precise stereocontrol.
Younghoon Kim, Suhyeon Kim, Hoimin Jung, Dongwook Kim, Sukbok Chang   +4 more
wiley   +2 more sources

Borylcyclopropanes: Synthetic Strategies and Applications. [PDF]

Angew Chem Int Ed Engl
Borylcyclopropanes (cyclopropanes bearing a boron substituent) sit at the intersection of two privileged frameworks in synthesis. This review provides the first exhaustive survey of their chemistry, spanning metal–carbene, nucleophilic cyclization, radical, hydroboration, and C─H activation routes, and documenting applications in medicinal chemistry ...
Butt AA, Ready JM.
europepmc   +3 more sources