1422773-18-9Relevant articles and documents
Imidazo[1,5-a]pyridin-3-ylidenes as π-accepting carbene ligands: substituent effects on properties of N-heterocyclic carbenes
Koto, Yuma,Shibahara, Fumitoshi,Murai, Toshiaki
, p. 1810 - 1820 (2017)
Various 1-substituted-imidazo[1,5-a]pyridin-3-ylidenes were prepared and characterized. The fundamental character and the effects of substituents on the imidazo[1,5-a]pyridine backbone on the electronic character of carbenes were evaluated using rhodium complexes and selenium adducts. 13C NMR chemical shifts of carbene carbons in imidazo[1,5-a]pyridin-3-ylidene and 1H and 13C NMR spectra of olefin moieties trans to the carbene in Rh(nhc)(cod)Cl complexes shifted relatively downfield compared to those for the corresponding complexes bearing conventional N-heterocyclic carbenes (NHCs). The IR peak of the trans-carbonyl moiety of Rh(nhc)(CO)2Cl complexes appeared at a higher wavenumber than for conventional NHCs. These observations suggest that imidazo[1,5-a]pyridin-3-ylidene ligands have strong π-accepting character. Rh(nhc)(CO)2Cl complexes were further characterized by X-ray diffraction analyses. To obtain further insight into the electronic character of imidazo[1,5-a]pyridin-3-ylidenes, selenoureas were prepared. We found that a combination of both the 77Se NMR chemical shift and 1JC-Se coupling constant of C-Se bonds are appropriate for a rigorous evaluation of the electronic characters of imidazo[1,5-a]pyridin-3-ylidenes, but did not correspond to those for conventional NHCs. DFT calculations for imidazo[1,5-a]pyridin-3-ylidenes revealed that a hybrid accepting orbital comprised of a vacant p-orbital of carbene and a π* orbital of the pyridine ring newly occurred to result in significantly increased π-accepting character. Finally, the strong π-accepting character of the ligand was demonstrated by the Rh-catalyzed polymerization of phenylacetylene.
AMINOPYRIMIDINE COMPOUNDS, PREPARATION METHODS AND USES THEREOF
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Paragraph 268, (2021/12/12)
Provided herein are novel compounds, for example, compounds having a Formula (I) or Formula (II), or a pharmaceutically acceptable salt thereof. Also provided herein are methods of preparing the compounds and methods of using the compounds, for example, for treating various cancer described herein, such as lung cancer (e.g., non-small cell lung cancer).
Pyrrolopyrazines as selective spleen tyrosine kinase inhibitors
Padilla, Fernando,Bhagirath, Niala,Chen, Shaoqing,Chiao, Eric,Goldstein, David M.,Hermann, Johannes C.,Hsu, Jonathan,Kennedy-Smith, Joshua J.,Kuglstatter, Andreas,Liao, Cheng,Liu, Wenjian,Lowrie, Lee E.,Luk, Kin Chun,Lynch, Stephen M.,Menke, John,Niu, Linghao,Owens, Timothy D.,O-Yang, Counde,Railkar, Aruna,Schoenfeld, Ryan C.,Slade, Michelle,Steiner, Sandra,Tan, Yun-Chou,Villase?or, Armando G.,Wang, Ce,Wanner, Jutta,Xie, Wenwei,Xu, Daigen,Zhang, Xiaohu,Zhou, Mingyan,Lucas, Matthew C.
supporting information, p. 1677 - 1692 (2013/04/10)
We describe the discovery of several pyrrolopyrazines as potent and selective Syk inhibitors and the efforts that eventually led to the desired improvements in physicochemical properties and human whole blood potencies. Ultimately, our mouse model revealed unexpected toxicity that precluded us from further advancing this series.