Transglycosylation Reactions of 6-Thioguanine Acyclonucleosides
摘要:
9-(2-Acetoxyethoxy)methyl-N-2-acetyl-6-thioguanine (2) undergoes two different transglycosylation reactions: i) the 7 reversible arrow 9 isomerization, which gives the respective 7-regioisomer (3) as the major product ii) the 9 reversible arrow S-6 glycosyl migration, which leads to a 9,S-6-disubstituted product (4). S-6-Methylation completely stopped the reversibility of transglycosylation.
Transglycosylation Reactions of 6-Thioguanine Acyclonucleosides
摘要:
9-(2-Acetoxyethoxy)methyl-N-2-acetyl-6-thioguanine (2) undergoes two different transglycosylation reactions: i) the 7 reversible arrow 9 isomerization, which gives the respective 7-regioisomer (3) as the major product ii) the 9 reversible arrow S-6 glycosyl migration, which leads to a 9,S-6-disubstituted product (4). S-6-Methylation completely stopped the reversibility of transglycosylation.
Chemoselective Perfluoromethylation of Thio- and Selenoamides
作者:Xianhong Xu、Jianyu Zhang、Tao Xu
DOI:10.1021/acs.orglett.0c03241
日期:2020.11.6
A chemo- and regioselective perfluoromethylation using thioamides/selenoamides (prepared one step from corresponding lactams) as starting materials has been discovered. The reaction demonstrated complementary chemoselectivity to the C-H trifluoromethylation of (hetero)arenes as well as remarkable functional group compatibility especially toward radical sensitive olefin-, alkyne-, and arylhalide-bearing substrates. The examples of perfluorothio-/selenolated drug molecules indicated application potential of this strategy in drug modification and drug-analogue preparation.
Boryski, Jarzy; Manikowski, Andzej, Collection of Czechoslovak Chemical Communications, 1996, vol. 61, p. S9 - S11