157373-97-2Relevant articles and documents
Rapid Bergman cyclization of 1,2-diethynylheteroarenes
Kim, Chang-Sik,Russell
, p. 8229 - 8234 (1998)
The synthesis and cyclization of acyclic quinoxaline, pyridine, and pyrimidine enediynes (1-3) are described. These compounds were prepared using palladium(0) coupling of trimethylsilyl acetylene to o-dihalo- or o- halotriflic heteroarenes. All compounds were prepared in modest to good yields. The enediynes prepared were shown to undergo Bergman cyclization. Kinetics over a minimum of 3 half-lives were used to construct ]Arrhenius plots. Pyrimidine 3 was found to have an activation energy of 16.1 kcal/mol. Cyclization of the closest known aromatic analogue, o-diethynylbenzene (15), has E(a) = 25.1 kcal/mol (Grissom, J. W.; Calkins, T. L.; McMillen, H. A.; Jiang, Y. J. Org. Chem. 1994, 59, 5833-5835). Pyridine 2 and quinoxaline 1 gave activation energies of 21.5 and 33.6 kcal/mol, respectively. The results illustrate that heteroarenes can be used to activate Bergman cyclization. We expect these compounds to play an important role in furthering the understanding of Bergman cyclization and in aiding the development of new biologically significant enediynes.
PURINONES AS UBIQUITIN-SPECIFIC PROTEASE 1 INHIBITORS
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Paragraph 00255, (2017/06/12)
The application relates to inhibitors of USP1 useful in the treatment of cancers, and other USP1 associated diseases and disorders, having the Formula: (I), where R1, R2, R3, R3', R4, R5, X1, X2, X3, X4, and n are described herein.
4-Piperidinecarboxamide modulators of vanilloid VR1 receptor
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Page/Page column 53, (2010/11/08)
This invention is directed to vanilloid receptor VR1 ligands. More particularly, this invention relates to hetero isonipecotic amides that are potent modulators of VR1 which are useful for the treatment and prevention of disease conditions in mammals.