Synthesis Of Heterocyclic Compounds Containing Triazoles

Studying on the synthesis of heterocyclic compounds and their biologic activity isone of the most spirited fields in organic chemistry. Heterocyclic compounds liketriazoles, thiadiazoles, pyrazoles,oxadiazoles have showed broad spectrum of biologicalactivities, such as antifungal, anticancer, antiviral, herbicidal. Their relatedcompounds have found useful in medicine, agriculture and industry. But differentsubstituted group in the heterocyclic compound will have great influence on thebioactivity of compounds.Triazole compounds have been found to show wide spread biological activities,many of them have been developed and used as fungicides, plant growth regulators andmedicine. In this thesis, We have reviewed the recent advances in the studies on thestructures, synthesis, action mechanism, structure-activity relationship and biologicalactivities of triazoles, different active groups of action mechanism were induced into thetriazole compounds according to the concept of bioisosterism. Thirty-four novel triazolecompounds in four big systems were designed and synthesized.In the first part, ten novel fused heterocyclic compounds Schiff bases have beensynthesized by reaction of 3-alky-4amino-5-mercapto-1,2,4-triazoles with salicyl-aldehyde, 5-nitro salicylaldenhyde, 3-nitro salicylaldenhyde, 5-bromo salicyl- aldenhyde, heliotropine in the of hydrochloric acid at 80℃for 10hr, their structures have beenconfirmed by EA, IR, ~1H NMR, X-ray crystallography analysis.In second part,3-alkyl-4-amino-5-mercapto-1,2,4-triazole compounds are one ofmany triazole compounds, and have good pharmacology, such as acesodyne,diminishinflammation,sterilization,weeding,pesticide,antivirus,lower blood pressure andplant growth regulating activities etc. Twenty six new triazole compounds containing1,2,4-triazole group have been synthesized through jointing activity substructures.In third part, four compounds having the structure of 3-trifluoromethy-6-substituted triazolo[3,4-b]-1,3,4-thiadiazoles were synthesized from 3 trifluoromethyl-4-amino-5-mercapto-1,2,4-triazoles with 2-,3-,4-nicotinic acid andα-naphthyaceticacid using phosphorus oxychloride as a catalyst respectively. The structures of thesecompounds were characterized by using EA, IR, ~1H NMR. The reaction heated bytraditional and microwave method was compared in this chapter, Compared with thetraditional synthetic method, under the microwave radiation the same products wereobtained with shorter reaction time and higher yield.In fourth part 1,3,4-oxadiazole and its derivatives have received increasinginterests in the agrochemical and pharmaceutical fields because of their unique anddiverse biological properties. To get further information about their fungicidal activity,18 new compounds have been synthesized including these two basic activity structuresthrough jointing substructure both 1,3,4-oxadiazole and 1,2,4-triazole.