5-Amino-3H-thiazolo[4,5]pyrimidine-2-one → 5-Amino-3-(2',3,5'-tri-O-acetyl-beta-D-ribofuranosyl)-3H-thiazolo[4,5-d]pyrimidin-2-one
Reaction equation
[NH2:1][C:2]1[N:3]=[CH:4][C:5]2[S:10][C:9](=[O:11])[NH:8][C:6]=2[N:7]=1.C(O)(=O)C.C(O)(=O)C.C(O)(=O)C.C(O)(=O)C.C(O[C@@H:32]1[O:44][C@H:43]([CH2:45][O:46][C:47](=[O:49])[CH3:48])[C@@H:38]([O:39][C:40](=[O:42])[CH3:41])[C@H:33]1[O:34][C:35](=[O:37])[CH3:36])(=O)C>>[NH2:1][C:2]1[N:3]=[CH:4][C:5]2[S:10][C:9](=[O:11])[N:8]([C@@H:32]3[O:44][C@H:43]([CH2:45][O:46][C:47](=[O:49])[CH3:48])[C@@H:38]([O:39][C:40](=[O:42])[CH3:41])[C@H:33]3[O:34][C:35](=[O:37])[CH3:36])[C:6]=2[N:7]=1Participants
3
Conditions
- Temperature
- 150 °C
Procedure
Compound 86 (62 mg, 0.4 mmol), 1,2,3,5-tetra-O-acetyl-β-D-ribofuranose tetraacetate (128 mg, 0.4 mmol), and catalytic bis(p-nitrophenyl)hydrogen phosphate (13 mg, 0.04 mmol) were mixed and placed in a 500 ml flask. The reaction vessel was carefully placed under vacuum (˜5.0 mmHg) and lowered into an oil bath heated at 150° C. for 10 minutes. After cooling to room temperature, the solids were washed with ethyl acetate. The crude product was purified by flash column. (silica, 5 to 35% ethyl acetate gradient in chloroform) to yield 68 mg of compound 79 (40%) as a white solid as a white powder identical in all respects to material isolated in Example 38, step 2.