A One-pot Tandom Process To Imidazo/Thiazolotriazoles And Imidazolo/Triazoloquinoxalines

Heterocycles containing nitrogen play an important role in natural product, medicine and dyestuff. Amino acid, protein and alkaloid, which belong to the range of the heterocles,are closely related to biological process in nature. Barbital (a kind of hypnotics), penicillin and antihypertensive drug-captopril are assembled by the heterocylces. Triazoles represent an overwhelming and rapid developingfield in modern heterocyclic chemistry. Adegree of respectability has been bestowed for 1,2, 4-triazolederivatives due to their wide range of biological activitiessuch as antibacterial, antifungal, antitubercularandanticancer.Thiazolo[3,2-b]-1,2,4-triazole composes non-steroidal anti-inflammatory drugs (NSAIDs), which result in increased anti-inflammatory activity with reduced ulcerogenic potential. Some compounds containing Imidazoloquinoxalines are inhibitors of Apoptosis. Triazoloquinoxalines exhibit positive anticonvulsant activity and display remarkable activity against coxsackievirus B4, adenovirus type 7 and mycobacterium tuberculosis.Organic synthesis is the mainstream in academy and industry. In the process of the synthesis, many factors should be considered, such as the efficiency, environmentally friendly, the protection of natural resources and the cost. The tandem reaction is an arresting approach to solve these problems, and defines asin the same processthe reactants preceded two or more stepswithout any new operation. The tandem reaction is broadly used in total synthesis of nature products, combinational chemistry and heterocylces.Coupling reactions of aryl halides with N heterocycles are performed by many well-known reactions, such as the Ullmann Reaction, Buchwald Reaction and potassium tert-butoxide-assisted reaction. With drawbacks of the reactions above, some novel systems that are able to realize the coupling are still investigated. In this paper, a transition metal-free tandem process for the synthesis of imidazo [2,1-b]thiazole,triazolothiazole,1,2,4-triazoloquinoxalines and imidazoloquinoxalines was described. Theconstruction of this tricyclic system went through a one-pot condensation/nucleophilic aromatic substitutionapproach. This methodology applied to a broad range of substrates.With the new system, the compound, which has been reported to display the anticonvulsant activity, was synthesized in one-pot.