4914-73-2Relevant articles and documents
Palladium-Catalyzed Thiomethylation via a Three-Component Cross-Coupling Strategy
Wang, Ming,Qiao, Zongjun,Zhao, Jiaoyan,Jiang, Xuefeng
supporting information, p. 6193 - 6197 (2018/09/25)
In this report, the combination of masked inorganic sulfur and dimethyl carbonate was designed to achieve thiomethylated cross coupling of aryl chlorides. Remarkably, this powerful strategy realized thiomethylation of nucleosides bearing unprotected ribose, chloride-containing pharmaceuticals with late-stage coupling, and herbicides possessing multiple heteroatoms and steric hindrance. Moreover, this protocol is practically amenable to multigram-scale synthesis with a lower catalysis loading and a higher yield.
Production, characterization and synthetic application of a purine nucleoside phosphorylase from Aeromonas hydrophila
Ubiali, Daniela,Serra, Carla D.,Serra, Immacolata,Morelli, Carlo F.,Terreni, Marco,Albertini, Alessandra M.,Manitto, Paolo,Speranzab, Giovanna
experimental part, p. 96 - 104 (2012/04/11)
Purine nucleoside phosphorylase (PNP) from Aeromonas hydrophila encoded by the deoD gene has been over-expressed in Escherichia coli, purified, characterized about its substrate specificity and used for the preparative synthesis of some 6-substituted purine-9-ribosides. Substrate specificity towards natural nucleosides showed that this PNP catalyzes the phosphorolysis of both 6-oxo- and 6-aminopurine (deoxy)ribonucleosides. A library of nucleoside analogues was synthesized and then submitted to enzymatic phosphorolysis as well. This assay revealed that 1-, 2-, 6- and 7-modified nucleosides are accepted as substrates, whereas 8-substituted nucleosides are not. A few transglycosylation reactions were carried out using 7-methylguanosine iodide (4) as a d-ribose donor and 6-substituted purines as acceptor. In particular, following this approach, 2- amino-6-chloropurine-9-riboside (2c), 6-methoxypurine- 9-riboside (2d) and 2-amino-6-(methylthio)purine- 9-riboside (2g) were synthesized in very high yield and purity.
High-throughput five minute microwave accelerated glycosylation approach to the synthesis of nucleoside libraries
Bookser, Brett C.,Raffaele, Nicholas B.
, p. 173 - 179 (2007/10/03)
The Vorbrueggen glycosylation reaction was adapted into a one-step 5 min/130 °C microwave assisted reaction. Triethanolamine in acetontrile containing 2% water was determined to be optimal for the neutralization of trimethylsilyl inflate allowing for direct MPLC purification of the reaction mixture. When coupled with a NH3/methanol deprotection reaction, a high-throughput method of nucleoside library synthesis was enabled. The method was demonstrated by examining the ribosylation of 48 nitrogen containing heteroaromatic bases that included 25 purines, four pyrazolopyrimidines, two 8-azapurines, one 2-azapurine, two imidazopyridines, two benzimidazoles, three imidazoles, three 1,2,4-triazoles, two pyrimidines, two 3-deazapyrimidines, one quinazolinedione, and one alloxazine. Of these, 32 yielded single regioisomer products, and six resulted in separable mixtures. Seven examples provided inseparable regioisomer mixtures of -two to three compounds (16 nucleosides), and three examples failed to yield isolable products. For the 45 single isomers isolated, the average two-step overall yield ± SD was 26 ± 16%, and the average purity ± SD was 95 ± 6%. A total of 58 different nucleosides were prepared of which 15 had not previously been accessed directly from glycosylation/deprotection of a readily available base.
