Hydrochloric Acid → 1-Acetyl-3,5,7-trimethylpyrazolo[3,4-D]pyrimidine-4,6-dione

Reaction equation

[NH:1]([C:3]1[N:8]([CH3:9])[C:7](=[O:10])[N:6]([CH3:11])[C:5](=[O:12])[CH:4]=1)[NH2:2].[C:13](OC(=O)C)(=[O:15])[CH3:14].Cl.N1C=CC=[CH:23][CH:22]=1>>[C:13]([N:1]1[C:3]2[N:8]([CH3:9])[C:7](=[O:10])[N:6]([CH3:11])[C:5](=[O:12])[C:4]=2[C:22]([CH3:23])=[N:2]1)(=[O:15])[CH3:14]

Participants

Reactant 4

HCID 313Hydrochloric Acid

HCID 1049Pyridine

HCID 7918Acetic Anhydride

HCID 97642Uracil, 1,3-dimethyl-6-hydrazino-

Product 1

HCID 124177361-Acetyl-3,5,7-trimethylpyrazolo[3,4-D]pyrimidine-4,6-dione

Conditions

Temperature: 0 °C

Procedure

A mixture of Step 2 intermediate (8.0 g, 47.01 mmol) and acetic anhydride (40 ml) in dry pyridine (78 ml) were refluxed for 3 h. The reaction mixture was cooled to 0° C. and acidified with 1N HCl (200 ml). The solid obtained was collected by filtration, washed with 1 N HCl (25 ml), water (25 ml) and dried to give 6.9 g of the product as a white solid; 1H NMR (300 MHz, DMSO-d6): δ 2.71 (s, 3H), 2.96 (s, 3H), 3.37 (s, 3H), 3.50 (s, 3H).