Trimethylsilyl triflate → Uridine

Temperature

75 °C

A solution of N6 -benzoylaminopurine (Lancaster) (1.23 g, 5.16 mmol) stirring in anhydrous acetonitrile under an argon atmosphere was treated with BSA (3.82 ml, 15.48 mmol) at reflux for 3 hours. Upon cooling, a solution of N4 -acetyl-5',3'-di-O-acetyl-2'-O-methyl cytidine (2) (see above) (0.66 g, 1.72 mmol) in 20 ml anh. acetonitrile was added to the reaction mixture followed by TMStriflate (1.03 ml, 5.16 mmol). The reaction mixture was then heated to 75° C. for 16 hours while stirring under positive pressure argon. Upon cooling, an additional 1.03 ml (5.16 mmol) of TMStriflate was added, and the reaction heated to 75° C. for an additional 20 hours. Once cool, the reaction mixture was diluted with two volumes of dichloromethane and washed with sat. NaHCO3. The organic layer was then dried over Na2SO4 and evaporated in vacuo. Flash chromatography employing a gradient of 10 to 80% ethyl acetgate/hexanes afforded (1) as a white foam; 0.403 g, 50% yield. 1H NMR (CDCl3): 8.88 (br s, 1H, NH), 8.81 (s, 1H, H8), 8.31 (s, 1H, H2), 8.11-7.53 (m, 5H, benzoyl), 6.18 (d, J1'2,' =4.8, 1H, H1'), 5.41 (t, J3',2' =4.8, J3',4' =4.8, 1H, H3'), 4.75 (t, J2',1' =4.8, J2',3' =4.8, 1H, H2'), 4.50-4.34 (m, 3H, H4', H5', H5"), 3.44 (s, 3H, OCH3), 2.19 (s, 3H, OAc), 2.14 (s, 3H, OAc).

1. additionwas treated with BSA (3.82 ml, 15.48 mmol)
2. temperatureat reflux for 3 hours
3. temperatureUpon cooling
4. temperatureUpon cooling
5. temperaturethe reaction heated to 75° C. for an additional 20 hours
6. temperatureOnce cool
7. washwashed with sat. NaHCO3
8. dry with materialThe organic layer was then dried over Na2SO4
9. customevaporated in vacuo

ORD record

ord-9299850fc8a4434ca05dc8c7b1b20f25

Source dataset

uspto-grants-1999_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05962675