Simple method for fast deprotection of nucleosides by triethylamine-catalyzed methanolysis of acetates in aqueous medium

Abstract

Este trabalho apresenta um método simples, rápido e eficiente para a desacetilação de ribonucleosídeos acetilados, a partir de metanólise catalisada por trietilamina em meio aquoso. As transformações assistidas por micro-ondas favoreceram sensivelmente a velocidade de reação e forneceram os nucleosídeos desprotegidos em altos rendimentos e sob condições brandas. Além de tolerar a presença de diversos grupos funcionais e de fornecer produtos com alto grau de pureza, esta nova metodologia utiliza reagentes de baixo custo e toxicidade.A straightforward methodology for deacetylation of protected ribonucleosides was developed based on triethylamine-catalyzed solvolysis in aqueous methanol. Reactions are completed in a few minutes under microwave irradiation and the free nucleosides are obtained in high yield after simple evaporation of volatiles. Other important features include the involvement of readily available reagents and the compatibility with diverse functional groups, which make this process very attractive for broad application.

Synthesis and Evaluation of Some Uracil Nucleosides as Promising Anti-Herpes Simplex Virus 1 Agents

“…Protection removal for compounds 3 and 4 was achieved by splitting the ester blocking with an MeOH/NH 3 solution [ 46 , 47 , 48 , 49 ] to give 7 and 8 in a fairly moderate yield (≈55 to 80%), respectively, as revealed in Scheme 1 . The 1 H-NMR showed the appearance of the free OH protons in the range δ ≈ 4.5–4.9 ppm.…”

Synthetic avenues towards a tetrasaccharide related to Streptococcus pneumonia of serotype 6A

“…The L-rhamnosyl thioglycoside 14 [ 29 – 30 ], prepared from L-rhamnose ( 13 ), was deacetylated quantitatively in the presence of Et 3 N/MeOH/H 2 O [ 35 ], and then stannylene-mediated selective naphthylmethylation at the O-3 position was carried out to give the known derivative 15 in 82% yield [ 36 ]. This was next benzoylated almost quantitatively to give 16 .…”

Orthoester functionalizedN-guanidino derivatives of 1,5-dideoxy-1,5-imino-d-xylitol as pH-responsive inhibitors of β-glucocerebrosidase

“…In doing so fully deprotected orthoester-armed guanidine products 10 and 11 were obtained in high yields. 45 The inhibitory potencies of DIX derived guanidineorthoesters 10 and 11 were determined against a panel of readily available glycosidase enzymes as well as the human recombinant enzymes, β-glucocerebrosidase (GBA) and β-galactocerebrosidase (GALC). Against the plant β-glucosidases screened, IC 50 values in the low micromolar range were observed for both compounds 10 and 11.…”