1. A study of the efficiency and the problem of sulfonation of several condensing reagents and their mechanisms for the chemical synthesis of deoxyoligoribonucleotides
A K Seth, E Jay Nucleic Acids Res. 1980 Nov 25;8(22):5445-59. doi: 10.1093/nar/8.22.5445.
The efficiencies and problems of sulfonation of several condensing reagents for deoxyoligoribonucleotide synthesis have been studied. While 2,4,6-triisopropylbenzenesulfonyl chloride (TPSC1) gave very low yield and slow rate of coupling, the new 1:3 mixture of TPSC1 and tetrazole afforded excellent yield and extremely fast rate of reaction with the lowest rate of sulfonation. The difference and advantages of this mixture over triisopropylbenzenesulfonyl tetrazole (TPSTe) and mesitylenesulfonyl tetrazole (MSTe) are discussed. Mechanisms for the coupling reactions with these condensing reagents to account for the difference in their rates and yields of coupling are discussed.
2. Homo-C-nucleoside analogs III. Studies on the base-catalyzed dehydrative cyclization of 4-(d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole
Mohammed A E Sallam Carbohydr Res. 2010 Oct 13;345(15):2233-8. doi: 10.1016/j.carres.2010.06.014.
Treatment of 4-(d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole with one molar equivalent of 2,4,6-triisopropylbenzenesulfonyl chloride (TIBSCl) in pyridine solution afforded the homo-C-nucleoside analog; 4-(2,5-anhydro-d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole in 54% yield and 4-(α-d-arabinopyranosyl)-2-phenyl-2H1,2,3-triazole analog in 3% yield. The 4-(5-O-triisopropylbenzenesulfonyl)-d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole analog was isolated as an intermediate and identified as its tetra-O-acetyl derivative. The 4-(5-chloro-5-deoxy-d-manno-pentitol-1-yl)-2-phenyl-2H-1,2,3-triazole analog was isolated as a byproduct. The structure and anomeric configuration of the products were determined by acylation, NMR spectroscopy, and mass spectrometry.
3. Synthesis of sialic acid-containing nucleotide sugars: CMP-sialic acid analogs
K Ikeda, Y Nagao, K Achiwa Carbohydr Res. 1992 Feb 7;224:123-31. doi: 10.1016/0008-6215(92)84099-e.
Syntheses of some sialic acid-containing nucleotide sugars are reported. The reaction of methyl [(2-hydroxy)ethyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galacto -2-nonulopyranosid]onate (4) with various fully protected hydrogen phosphonates of nucleosides (5a-c) in the presence of 2,4,6-triisopropylbenzenesulfonyl chloride (TPSCl), gave, after oxidation and deprotection, the corresponding sialic acid-containing nucleotide sugar analogs (8a-c).