Synthesis and enzymatic evaluation of phosphoramidon and its β anomer: Anomerization of α-l-rhamnose triacetate upon phosphitylation

Efficient Synthesis of UDP-Furanoses via 4,5-Dicyanoimidazole(DCI)-Promoted Coupling of Furanosyl-1-Phosphates with Uridine Phosphoropiperidate

“…Alternatively, furanosyl-1-phosphates have been prepared from thiofuranosides [30,35]. Based on our previous research on the phosphorylation of saccharides and nucleosides [36,37], we attempted to synthesize furanosyl-1-phosphates via a phosphoramidite route. As shown in Scheme 1, phosphitylation of 1-OH of Bz-protected furanoses 1 – 4 with benzyl- N , N -diisopropylchlorophosphoramidite, 1 H -tetrazole- catalyzed alcoholysis, and in situ oxidation with H 2 O 2 afforded crude 5 – 8 in good yields over three consecutive fast steps.…”

“…Although the P(V)-N activation strategy yielded an excellent result in the coupling step, we were also clearly aware of the possibility that the final deprotection step may cause undesired decomposition to sugar 1,2-cyclic phosphate. As shown in Scheme 2, both MeOH/H 2 O/Et 3 N (7:3:1) [38] and MeONa/MeOH [36] deprotection methods caused almost total breakdown of 15 to equal amounts of 1,2-cyclic phosphate and UMP, while the MeOH/TEAB buffer/Et 3 N (3:4:0.05) method reported by Williams et al [39] was not effective at the claimed low temperature (−20 °C). The above experimental results reveal that the UDP- l -Ara f has very strong tendency to decompose via the intramolecular cyclization under basic conditions at room temperature.…”

Probing the Influence of Linker Length and Flexibility in the Design and Synthesis of New Trehalase Inhibitors

“…Selective deprotection of 27 with ethylendiamine in acetic acid following the procedure reported by Sun et al [ 17 ] afforded in 86% yield compound 28 , that was treated with trichloroacetonitrile to obtain 29 in 85% yield. Glycosylation reaction with 15 at 0 °C in dry CH 2 Cl 2 in the presence of TMSOTF (1.5 equiv) afforded 39% yield of the β-glucoside 30 as the major compound, although impure of a partially deacetylated isomer (See Supplementary Materials ).…”