| 摘要 |
1,126,757. Purine derivatives. AJINOMOTO CO. Inc. 16 Nov., 1966 [16 Nov., 1965 (2); 15 Dec., 1965], No. 51449/66. Heading C2C. The invention comprises purine derivatives of the formula where R represents a hydroxyl, methoxy or ethoxy group or a chlorine atom, and salts thereof. The 6-alkoxypurine-3-N-oxide derivatives may be obtained by oxidizing the corresponding purine with hydrogen peroxide or an organic acid peroxide, preferably at about room temperature and generally in the presence of a solvent. The 6-chloropurine-3-N-oxide may be obtained by the oxidation of the corresponding chloropurine under conditions similar to those described above except that the reaction is carried out under anhydrous conditions. Hypoxanthine-3-N-oxide may be obtained by heating the 6-chloro- or 6-alkoxy-purine-3-N- oxides described above in aqueous alkaline solution. The above purine compounds may be converted to other purine derivatives and in specific examples 6,8-dioxypurine is prepared from hypoxanthine-3-N-oxide by reaction with formic acid or acetic acid, xanthine and 6,8- dioxypurine, are obtained by reacting hypoxanthine-3-N-oxide with acetic anhydride and subsequent hydrolysis, 6,8-dichloropurine (also some 2,6-dichloropurine) is obtained by reacting hypoxanthine-3-N-oxide with phosphorus oxychloride in the presence of N,N-dimethyl aniline, 8-mercaptohypoxanthine (also some 2-mercaptohypoxanthine) is obtained by reacting hypoxanthine-3-N-oxide with thioacetic acid and guanine is obtained by reacting hypoxanthine-3-N-oxide with acetic acid/pyridine to form 1-(2-hypoxanthyl) pyridinium acetate which is subsequently hydrolysed. |
