(2R,3S,4S,5S)-5-(acetoxymethyl)tetrahydrofuran-2,3,4-triyl triacetate → Methyl 1-(2,3,5-Tri-O-acetyl-beta-L-ribofuranosyl)-1,2,4-triazole-3-carboxylate

A mixture of methyl 1,2,4-triazole-3-carboxylate (0.64 g, 5 mmol), 1,2,3,5-tetra-O-acetyl-β-L-ribofuranose (2) (1.5 g, 4.72 mmol) and bis(p-nitrophenyl)-phosphate (20 mg) were placed in a pear shaped flask and placed in a preheated oil bath at (160-165° C.). The flask was connected to a water aspirator and kept at 160-165° C. (oil bath temperature) under reduced pressure with stirring for 25 min. The reaction mixture was removed, cooled and diluted with EtOAc (150 mL) and sat. NaHCO3 (100 mL). The product was extracted in EtOAc. The organic extract was washed with water (100 mL) and brine (50 mL), dried and evaporated to dryness. The residue that obtained was purified by flash column of silica gel using CHCl3→EtOAc as the eluent. The pure fractions were collected and evaporated to dryness to give 1.2 g (66%) of pure product: 1H NMR (CDCl3) δ2.10 (3s, 9H, 3 COCH3), 3.98 (s, 3H, OCH3), 4.22 (m, 1H), 4.46 (m, 2H), 5.54 (t, 1H), 5.76 (m, 1H), 6.04 (d, 1H, C1′H), and 8.38 (s, 1H, C3H). Anal. Calc. for C15H19N3O9 (385.22): C, 46.75; H, 4.97; N,10.91. Found: C, 46.82; H, 4.57; N=10.71.

1. customwere placed in a pear shaped flask
2. customplaced in a preheated oil bath at (160-165° C.)
3. customkept at 160-165° C.
4. customThe reaction mixture was removed
5. temperaturecooled
6. additiondiluted with EtOAc (150 mL) and sat. NaHCO3 (100 mL)
7. extractionThe product was extracted in EtOAc
8. extractionThe organic extract
9. washwas washed with water (100 mL) and brine (50 mL)
10. customdried
11. customevaporated to dryness
12. customThe residue that obtained
13. customwas purified by flash column of silica gel
14. customThe pure fractions were collected
15. customevaporated to dryness

ORD-Eintrag

ord-f565d3671181431e86fa343ac4dd12da

Quelldatensatz

uspto-grants-2003_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06573248B2