Results 31 to 40 of about 13,090 (233)

Reactions and Syntheses of Pyrazines

YAKUGAKU ZASSHI, 1997
This review deals with syntheses and reactions of pyrazines, especially, of 2,5-disubstituted pyrazines. The description was made in due to order of 1) synthesis and properties of 2,5-disubstituted pyrazines, 2) synthesis of 2,5-disubstituted pyrazine N-oxides, 3) synthesis of pyrazinols, 4) synthesis and utilization of pyrazinethiols; preparation of ...
A, Ohta, Y, Aoyagi
openaire   +3 more sources

High Charge Carrier Mobility in Non‐Conjugated 3D Covalent Organic Frameworks

Advanced Materials, EarlyView.
A non‐conjugated 3D COF constructed via boronate ester linkages from tetraphenylene and pyrene‐based monomers is reported, which exhibits a high charge carrier mobility of 14 ± 1 cm2 V−1 s−1. ABSTRACT π‐Conjugation, π–π stacking, and long‐range order play a central role in determining charge transport efficiency in organic materials.
Joaquín Almarza, Karol Strutyński, Shuai Fu, Yifan Chen, Natalia M. Padial, Isabel del Barrio Gómez, Carlos Martí‐Gastaldo, Andrei N. Khlobystov, Mischa Bonn, Hai I. Wang, Manuel Melle‐Franco, Aurelio Mateo‐Alonso   +11 more
wiley   +1 more source

Iridium‐Catalyzed Ionic Hydrogenation of Multi‐Aza Heterocycles

Angewandte Chemie, EarlyView.
Saturated nitrogen‐containing heterocycles are ubiquitous in bioactive molecules and are thus attractive synthetic targets. A readily accessible cyclometalated iridium(III) complex reduces 14 different aromatic aza heterocycles to (partially)saturated multi aza‐heterocycles enlarging accessible chemical space while displaying high tolerance toward ...
Arthur Despois, Nicolai Cramer
wiley   +2 more sources

Streptavidins Coordinate Biotin Sequestration and Self‐Resistance Within a Biotin‐Pathway Antibiotic Network

Advanced Science, EarlyView.
A conserved genomic region between two streptavidin genes in Streptomyces packages biosynthetic gene clusters for diverse biotin‐pathway antibiotics: acidomycin, stravidin, the new non‐proteinogenic amino acid ANDA, and the new BioA inhibitor α‐methyl‐KAPA.
Sumire Kurosawa, Jingjun Mo, Xiaotong Diao, Feng Xie, Tingting Wang, Haowen Zhao, Dalei Wu, Rolf Müller, Chengzhang Fu   +8 more
wiley   +1 more source

Coordination‐Driven Direct C─H Metalation of N‐Heterocycles With a Superbasic Co(II) Amide Co(TMP)2

Angewandte Chemie, EarlyView.
By enabling regioselectivities that are inaccessible with conventional bases, this study introduces a Co(II) amide platform for the deprotonative C─H metalation of sensitive N‐heterocycles. Subsequent interception of the resulting Co(II) intermediates with external oxidants affords a family of sterically congested, TMP‐substituted heterocycles via C─N ...
Na Jin, Manting Mu, Max García‐Melchor, Eva Hevia   +3 more
wiley   +2 more sources

Discovery and Biological Evaluation of a Series of Pyrrolo[2,3-b]pyrazines as Novel FGFR Inhibitors

Molecules, 2017
Abnormality of fibroblast growth factor receptor (FGFR)-mediated signaling pathways were frequently found in various human malignancies, making FGFRs hot targets for cancer treatment. To address the consistent need for a new chemotype of FGFR inhibitors,
Yan Zhang, Hongchun Liu, Zhen Zhang, Ruifeng Wang, Tongchao Liu, Chaoyun Wang, Yuchi Ma, Jing Ai, Dongmei Zhao, Jingkang Shen, Bing Xiong   +10 more
doaj   +1 more source

Multimodal Imaging Reveals Rapid Catecholamine Uptake and Release by Neutrophils

Advanced Science, EarlyView.
We show that immune cells (neutrophils) synthesize, uptake, and store catecholamine neurotransmitters such as dopamine or adrenaline. They also release them in response to specific stimuli (serotonin), which we directly visualize using fluorescent nanosensors. We further demonstrate that catecholamines affect neutrophil functions (NETosis) and platelet
Jennifer Mohr, Anne Schmitz, Meshkat Dinarvand, Franziska Wulfert, Sangeetha Shankar, Bjoern F. Hill, Michael Wojak, Juliana Gretz, Marie Britz, Elsa Neubert, Magdalena Shumanska, Sofia Kaushik, Linda Kartaschew, Ivan Bogeski, James Daniel, Sebastian Jung, Johannes Eble, Guido Wabnitz, Luise Erpenbeck, Sebastian Kruss   +19 more
wiley   +1 more source

Synthesis of nanodiamond derivatives carrying amino functions and quantification by a modified Kaiser test

Beilstein Journal of Organic Chemistry, 2014
Nanodiamonds functionalized with different organic moieties carrying terminal amino groups have been synthesized. These include conjugates generated by Diels–Alder reactions of ortho-quinodimethanes formed in situ from pyrazine and 5,6-dihydrocyclobuta[d]
Gerald Jarre, Steffen Heyer, Elisabeth Memmel, Thomas Meinhardt, Anke Krueger   +4 more
doaj   +1 more source

Atroposelective Access to π‐Conjugated 1,2‐Azaborepines Enabled by Palladium‐Catalyzed Cyclization of N‐Heterobiaryls with Alkynylboronates

Advanced Science, EarlyView.
We report a palladium‐catalyzed atroposelective cyclization of N‐heterobiaryl triflates with alkynyl boronates to access seven‐membered 1,2‐BN‐bridged biaryls with high yields and excellent enantioselectivity via a cascade DyKAT, cis‐carbopalladation, and 1,2‐migration, which expands the toolbox for axially chiral π‐conjugated boron compounds and opens
Fengya He, Zhen Wang, Haoyu Guo, Shuguang Chen, Xu Zhang, Yongjia Shang, Hui Wang   +6 more
wiley   +1 more source

A Strong Lewis Acidic Diethylsilylium Catalyst for Direct Sulfonamidation of Challenging Ketones

Advanced Science, EarlyView.
Low‐substitution‐order silylium ions (R2HSi+) exhibit exceptional Lewis acidic activity. We report diethylsilylium‐catalyzed reductive sulfonamidation of functionalized ketones to access β‐amino esters. The in situ generated ion pair shows enhanced reactivity, with diethylsilane serving as both reductant and precatalyst. The developed protocol proceeds
Woo Hee Kim, Muhammad Israr, You Kyoung Chung, Shinwon Ham, Joonsuk Huh, Han Yong Bae   +5 more
wiley   +1 more source