- Synthesis method of 6-chloro-3-alkyl uracil
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The invention relates to a synthesis method of 6-chloro-3-alkyl uracil, which is characterized by comprising the following steps: by using malonic acid and N-alkyl urea as raw materials, carrying outthe cyclization reaction to generate alkyl tripyrimidone; and then carrying out chlorination on the alkyl tripyrimidone to generate the 6-chloro-3-alkyl uracil. Compared with an existing method, the method is mild in reaction and low in cost, high-cost and high-risk raw materials such as high-toxicity and high-boiling phosphorus oxychloride are not used, and industrial large-scale production is facilitated; meanwhile, the chemical purity obtained by the method is high, the yield is good, and the economic benefit is good.
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Paragraph 0056-0057
(2019/12/02)
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- PYRIMIDINEDIONE COMPOUNDS AGAINST CARDIAC CONDITIONS
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Provided are novel pyrimidine dione compounds and pharmaceutically acceptable salts thereof, that are useful for the treatment of hypertrophic cardiomyopathy (HCM) and conditions associated with left ventricular hypertrophy or diastolic dysfunction. The synthesis and characterization of the compounds and pharmaceutically acceptable salts thereof, are described, as well as methods for treating HCM and other forms of heart disease.
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Paragraph 0122-0123
(2015/01/07)
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- A facile synthesis of 5-acylbarbituric acids under microwave irradiations
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N-Monosubstituted and N,N'-disubstituted barbituric acids on treatment with benzoic anhydride/acetic anhydride under microwave irradiations without using any solvent provide a convenient methodology for the synthesis of 5-benzoyl/ acylbarbituric acids in moderate to high yields.
- Singh, Palwinder,Paul, Kamaldeep
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p. 1105 - 1108
(2007/10/03)
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- Pyrimido[5,4-e][1,2,4]triazine-5,7-diones, processes for preparing them and their use
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The invention relates to pyrimido[5,4-e][1,2,4]triazine-5,7-diones, pharmaceutically acceptable salts thereof and physiologically functional derivatives. The invention therefore relates to compounds of the formula I, in which the radicals have the given meanings, and to their physiologically tolerated salts and processes for preparing them. The compounds are suitable for use as antidiabetics, for example.
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- Synthesis of Paraxanthine Analogs (1,7-Disubstituted Xanthines) and Other Xanthines Unsubstituted at the 3-Position: Structure-Activity Relationships at Adenosine Receptors
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Synthetic procedures for the preparation of various 3-unsubstituted xanthines, including paraxanthine analogs (1,7-disubstituted xanthines) and 1,8-disubstituted xanthines, were developed.Sylylation of 1-substituted xanthines followed by alkylation at the 7-position provides a facile route to paraxanthine analogs.Regioselective alkylation of tris(trimethylsilyl)-6-aminouracil provides 3-substituted 6-aminouracils, which are converted to 1,8-disubstituted xanthines by standard procedures.The ring closure of 3-substituted 5-cyclopentanecarboxamido- and 5-(benzoylamino)-6-aminouracils requires drastic reaction conditions.Affinity for brain A1 and A2 adenosine receptors was determined in binding assays for these and other xanthines with substituents in 1-, 3-, 7-, 8-, and 9-positions.Substitution at the 1-position was necessary for high affinity at adenosine receptors. 1,3-Disubstituted xanthines generally had higher affinity than 1,7-disubstituted xanthines. 1,8-Disubstituted xanthines had high affinity for adenosine receptors; some were highly selective for A1 receptors.
- Mueller, Christa E.,Shi, Dan,Manning, Malcolm,Daly, John W.
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p. 3341 - 3349
(2007/10/02)
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- Effects of 8-phenyl and 8-cycloalkyl substituents on the activity of mono-, di-, and trisubstituted alkylxanthines with substitution at the 1-, 3-, and 7-positions
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The effects of 8-phenyl and 8-cycloalkyl substituents on the activity of theophylline, caffeine, 1,3-dipropylxanthine, 1,3-dipropyl-7-methylxanthine, 3-propylxanthine, and 1-propylxanthine at A1 adenosine receptors of rat brain and fat cels and at A2 adenosine receptors of rat pheochromocytoma PC12 cells and human platelets are compared. An 8-phenyl substituent has little effect on the activity of caffeine or 1,3-dipropyl-7-methylxanthine at adenosine receptors, while markedly increasing activity of theophylline, 1,3-dipropylxanthine, 1-isoamyl-3-isobutylxanthine, 1-methylxanthine, and 3-propylxanthine. 8-Phenyl-1-propylxanthine is potent (K(i) = 20-70 nM) at all receptors. A p-carboxy or p-sulfo substituent, which is introduced on the 8-phenyl ring to increase water solubility, in most cases decreases the activity and selectivity for the A1 receptor. Among the 8-p-sulfo analogues, only 8-(p-sulfophenyl)theophylline and 1,3-dipropyl-8-(p-sulfophenyl)xanthine are selective for the A1 receptors. 8-p-Sulfophenyl derivatives of caffeine, 1,3-dipropyl-7-methylxanthine, and 3-propylxanthine are somewhat selective for the A2 receptors. 8-Cycloalkyl substituents (cyclopentyl, cyclohexyl) markedly increase activity of caffeine and 1,3-dipropyl-7-methylxanthine at the A2 receptor. 8-Cyclohexylcaffeine is potent (K(i) = 190 nM) and very selective for the human platelet A2 receptors, but is not as selective for the rat PC12 cell A2 receptor. Such A2 selectivity is in contrast to the marked A1 selectivity of 8-cycloalkyltheophyllines and 8-cycloalkyl-1,3-dipropylxanthines. The apparent selectivity of certain xanthines is dependent on the assay systems that are compared.
- Shamim,Ukena,Padgett,Daly
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p. 1231 - 1237
(2007/10/02)
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