1802-20-6Relevant articles and documents
Practical and Selective sp3 C?H Bond Chlorination via Aminium Radicals
McMillan, Alastair J.,Sieńkowska, Martyna,Di Lorenzo, Piero,Gransbury, Gemma K.,Chilton, Nicholas F.,Salamone, Michela,Ruffoni, Alessandro,Bietti, Massimo,Leonori, Daniele
supporting information, p. 7132 - 7139 (2021/03/03)
The introduction of chlorine atoms into organic molecules is fundamental to the manufacture of industrial chemicals, the elaboration of advanced synthetic intermediates and also the fine-tuning of physicochemical and biological properties of drugs, agrochemicals and polymers. We report here a general and practical photochemical strategy enabling the site-selective chlorination of sp3 C?H bonds. This process exploits the ability of protonated N-chloroamines to serve as aminium radical precursors and also radical chlorinating agents. Upon photochemical initiation, an efficient radical-chain propagation is established allowing the functionalization of a broad range of substrates due to the large number of compatible functionalities. The ability to synergistically maximize both polar and steric effects in the H-atom transfer transition state through appropriate selection of the aminium radical has provided the highest known selectivity in radical sp3 C?H chlorination.
Synthesis and antiviral evaluation of 6-(alkyl-heteroaryl)furo[2,3-d] pyrimidin-2(3H)-one nucleosides and analogues with ethynyl, ethenyl, and ethyl spacers at C6 of the furopyrimidine core
Robins, Morris J.,Nowak, Ireneusz,Rajwanshi, Vivek K.,Miranda, Karl,Cannon, John F.,Peterson, Matt A.,Andrei, Graciela,Snoeck, Robert,De Clercq, Erik,Balzarini, Jan
, p. 3897 - 3905 (2008/02/10)
Sonogashira coupling strategies were employed to synthesize new furo[2,3-d]pyrimidin-2(3H)-one (FuPyrm) 2′-deoxynucleoside analogues. Partial or complete reduction of ethyne-linked compounds afforded ethenyl-and ethyl-linked derivatives. Levels of inhibition of varicella-zoster virus (VZV), human cytomegalovirus (HCMV), a broad range of other DNA and RNA viruses, and several cancer cell lines were evaluated in cell cultures. The anti-VZV potency decreased with increasing rigidity of the side chain at C6 of the FuPyrm ring in the order dec-1-yn-1-yl dec-1-en-1-yl decan-1-yl. In contrast, compounds with a rigid ethynyl spacer between C6 of the FuPyrm ring and a 4-alkylphenyl moiety were more potent inhibitors of VZV than the corresponding derivatives with an ethyl spacer. Replacement of the phenyl moiety in 6-(4-alkylphenyl) derivatives with a pyridine ring (in either regioisomeric orientation) gave analogues with increased solubility in methanol but reduced anti-VZV potency, and replacement with a pyrimidine ring reduced the anti-VZV activity even further. The pyridine-ring-containing analogues were ～20-fold more potent inhibitors of VZV than acyclovir but were ～6-fold less potent than BVDU and ～60-fold weaker than the most active 6-(4-pentylphenyl)- substituted prototype.
Formation of 2-Pentylpyridine from the Thermal Interaction of Amino Acids and 2,4-Decadienal
Kim, Young-Suk,Hartman, Thomas G.,Ho, Chi-Tang
, p. 3906 - 3908 (2007/10/03)
To study the mechanism of 2-pentylpyridine formation in model systems, 2,4-decadienal was reacted with five amino acids (glycine, aspartic acid, asparagine, glutamic acid, and glutamine) at 180°C for 1 h (pH 7.5). In addition to 2-pentylpyridine, 3-pentylpyridine was also tentatively identified from the thermal reactions. The relative yields of alkylpyridine formation from the reactions were asparagine > glutamine > aspartic acid > glutamic acid > glycine. When amide-15N-labeled glutamine and asparagine were heated with 2,4-decadienal, the relative contribution of amide nitrogens to the formation of alkylpyridine was determined. Approximately half of nitrogen atoms in 2-pentylpyridine formed were contributed by the amide nitrogens of asparagine, whereas almost all of them came from the amide nitrogens in glutamine. The results above may indicate that both free ammonia and α-amino groups bound in amino acids can contribute to the formation of alkylpyridines, but free ammonia does so more effectively.
