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ChemicalBook CAS DataBase List Diprophylline
479-18-5

Diprophylline synthesis

7synthesis methods
-

Yield:479-18-5 52%

Reaction Conditions:

with sulfuric acid;water in acetone; pH=1 at 50 - 60; for 2 h;

Steps:

Synthesis of 7-(2,3-dihydroxypropyl)-1,3-dimethyl-3,7-dihydro-1H-purine-2,6-dione (Diprophylline, rac-7)
To a solution of rac-3 (200 mg, 0.85 mmol) in acetone (7 mL), distilled H2O (3 mL) was added at 50-60 °C. Next, the aqueous phase was acidified to pH 1 with a 50% H2SO4, and the reaction was stirred for 2 h until complete consumption of the substrate (according to TLC). Afterwards, the content of the flask was neutralized using saturated solution of NaHCO3, and after separating an organic phase, the solvents were evaporated to dryness under reduced pressure. The oil residue was further refluxed in EtOH (10 mL) for 10 minutes, and the remaining solid of inorganic salts was filtered off. The filtrate was concentrated under reduced pressure, and the crude oil was purified by column chromatography on SiO2 using mixture of CHCl3/EtOH/25% NH3aq. (90:10:1, v/v/v) as an eluent to furnish diprophylline rac-7 (111 mg, 0.85 mmol, 52 %) as a white solid.

References:

Borowiecki, Pawe?;M?ynek, Mateusz;Dranka, Maciej [Bioorganic Chemistry,2021,vol. 106,art. no. 104448] Location in patent:supporting information

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