Synthesis Of Multiple Substitute Purine Derivatives With New Catalytic System

As an important endogenous substance of organism, purine derivativesextensively participate in kinds of life activities such as genetic or metabolic. Purinederivatives are a kind of important antiviral drug intermediates because of it′swell-known biomedical activities. This dissertation mainly studies the fast andefficient methods for synthesis of purine derivatives. The diverse purine derivativeslibraries were constructed by using new types of catalytic system, which facilitates todiscover new and high activity of purine drugs.A series of O6-substituted purine derivatives were designed and prepared rapidlythrough an efficient and convenience method. The reaction was developed under thecatalyst of4-amino-pyridine. Under the optimum conditions of n (6-chloropurine): n(4-amino-pyridine): n (triethylamine)=10:1:4, in refluxing for5~7h, the yield of6-alkoxy purine was more than85%. Studies show that, the relative amount of6-chloropurine,4-amino-pyridine and triethylamine in the system has a greatinfluence on the reaction, and the4-amino-pyridine-triethylamine as catalytic systemwas more effective.A series of6,8,9-trisubstituted purine derivatives were synthesized from4,6-dichloro-5-pyrimidine via three step reactions: aminolysis, cyclization, andaminolysis of purine. All the reactions were catalyzed by the polyethyleneglycol1000-dicationic acidic ionic liquid (PEG1000-DAIL). Compared to other syntheticmethods, this method not only enhanced the yield, but also avoided the hydrolysis ofthe chloride to the hydroxyl group during the cyclization. The product can be isolatedeasily and the catalytic system can be recycled and reused without any significant lossof catalytic activity.A series of9-alkylpurine derivatives were synthesized by the N9-alkylation of2,6-disubstituted-9H-purine derivatives. The reaction was carried out by the catalyst of1-butyl-3-methylimidazolium cation and imidazolide anion ([Bmim]Im). Under theoptimum conditions of n (2,6-disubstituted-9H-purine): n (bromoalkane)=1:1.2, with10.0mmol2,6-disubstituted-9H-purine,6.0g [Bmim]Im and30mL DMF as solvent,0℃for6h, the yield of9-alkylpurine derivatives could achieve to86%. This methodsolved the problem of the appearing of byproduct, and raised the yield of aim product,and made the treatment process more convenient at the same time.According to the determined route and optimum reaction conditions, a series of substituted purine derivatives were designed and prepared. All of the preparedcompounds were characterized by1H NMR, MS and elemental analysis.