85-18-7Relevant articles and documents
Reactions of theophyllines. Chemical conversions of 8-aminotheophyllinates
Kuz'menko,Zvolinskaya
, p. 963 - 970 (2000)
Thermally stable, colored 8-aminotheophyllinates (betaine derivatives of theophylline) form unstable, colorless salts with strong mineral acids and undergo partial decomposition to a uric acid upon prolonged refluxing with concentrated base solution. Substituted 8-pyridinium theophyllinates readily take part in typical reactions of the functional group in the substituted pyridine ring with retention of the betaine structure. The formation of the synthesized compounds was confirmed by IR and NMR spectroscopy.
Preparation method of low-cost 8-chlorotheophylline
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Paragraph 0019; 0020; 0021; 0022; 0023; 0024; 0025-0038, (2017/08/29)
The invention discloses a preparation method of low-cost 8-chlorotheophylline. The preparation method of the low-cost 8-chlorotheophylline comprises the following steps: adding theophylline into a mixed solution of DMF and SOCl2, introducing chlorine to react, and crystallizing, washing and drying after the reaction to obtain the final product. According to the method, the target product is synthesized by taking the recyclable DMF as a solvent at one step and the finished product can be obtained by pulping with tap water, so that the cost is low, the pollution is low and the yield is high.
Purines. XIV [1]. Synthesis and properties of 8-nitroxanthine and its N- methyl derivatives
Mosselhi,Pfleiderer
, p. 1221 - 1228 (2007/10/02)
Xanthine (1) and its N-methyl derivatives 2-16 have been nitrated to the corresponding 8-nitro derivatives 17-32 under different reaction conditions. Nitration in glacial acetic acid with nitric acid works well with the N-7 unsubstituted and some of the 9-methylxanthines, respectively, whereas the 7- methylxanthine derivatives react best with nitronium tetrafluoroborate in sulfolane or glacial acetic acid. The 8-nitro group can be displaced nucleophilically to form 8-chloro-, 33, 34, 8-ethoxy-, 35, 36, and uric acid derivatives 37-40, respectively. The newly synthesized 8-nitroxanthines have been characterized by elemental analyses, pK-determinations and uv and 1H- nmr spectra.