78174-93-3Relevant academic research and scientific papers
C?H Methylation of Iminoamido Heterocycles with Sulfur Ylides**
Ghosh, Prithwish,Kwon, Na Yeon,Kim, Saegun,Han, Sangil,Lee, Suk Hun,An, Won,Mishra, Neeraj Kumar,Han, Soo Bong,Kim, In Su
, p. 191 - 196 (2021)
The direct methylation of N-heterocycles is an important transformation for the advancement of pharmaceuticals, agrochemicals, functional materials, and other chemical entities. Herein, the unprecedented C(sp2)-H methylation of iminoamido heterocycles as nucleoside base analogues is described. Notably, trimethylsulfoxonium salt was employed as a methylating agent under aqueous conditions. A wide substrate scope and excellent level of functional-group tolerance were attained. Moreover, this method can be readily applied to the site-selective methylation of azauracil nucleosides. The feasibility of gram-scale reactions and various transformations of the products highlight the synthetic potential of the developed method. Combined deuterium-labeling experiments aided the elucidation of a plausible reaction mechanism.
Photochemical Reactions of Pyrazin-2(1H)-ones
Nishio, Takehiko,Nakajima, Naoko,Kondo, Masaji,Omote, Yoshimori,Kaftory, Menahem
, p. 391 - 396 (2007/10/02)
Irradiation of 1-alkyl-5,6-diarylpyrazin-2(1H)-ones (1a-c) in alcohol under oxygen gave N-alkylacetamide derivatives (2a-e) in 21-69percent yield.The formation of acetamide derivatives (2) arises via the endoperoxide intermediates (3), initially produced by the reaction of the pyrazin-2(1H)-ones (1), which act as their own sensitizer, with singlet oxygen followed by O-O bonds fission, alcohol addition, and rearrangement accompanied by the elimination of the corresponding nitrile derivative.The pyrazin-2(1H)-ones (1a-d) rapidly reacted with singlet oxygen to afford the stable endoperoxides (3a-d).On the other hand, the pyrazin-2(1H)-ones (1a-d) were inert to the photolysis in benzene or methanol under argon.
