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ChemicalBook CAS DataBase List Xanthine
69-89-6

Xanthine synthesis

10synthesis methods
Xanthine is a purine base widely distributed in the organs and body fluids of the human body and other organisms. It is often used as a mild stimulant and bronchodilator, especially for the treatment of Asthma. It can be obtained by the reaction of 4-amino-5-formamidocarbazine and formamide at 180-185°C.
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Yield:69-89-6 9.2 g (60%)

Reaction Conditions:

in sodium hydroxide;(CH2)3 COOEt;N,N-dimethyl-formamide;

Steps:

2 (Method B, xanthine no. 21)

EXAMPLE 2 1-(4-hydroxybutyl)-3-butyl xanthine (Method B, xanthine no. 21) 11.3 g (0. 05 mole) of 1-butyl-5-formylamino-6-aminouracil (II) (R1 =butyl, R8 =H) are dissolved under nitrogen in 200 ml of DMF. 10.6 ml (0.075 mole) of ethyl 4-bromobutyrate are added, after which 2 g (0.05 mole) of solid powder-form NaOH is added with thorough stirring in portions of 0.5 g at intervals of 1 hour. On completion of the addition, the mixture is left to react overnight. The solvent is then evaporated and the oily residue of (IV) (substituent in the 1-position=(CH2)3 COOEt) is dissolved in 100 ml of 10% NaOH. This solution is then heated under reflux for 0.5 hour and then cooled, neutralized to pH 5 with acetic acid and filtered. The precipitate formed is dried. Yield: 9.2 g (60%) of crude xanthine (V) (substituent in the 1-position=(CH2)3 COOH, R3 =butyl, R8 =H).

References:

US5338741,1994,A

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