Synthesis And Biological Activities Of Glucopyranosylthiourea Componds Containing A Moiety Of Pyrazole

Carbohydrates are the main source for all the organisms to maintain life activities. As the endogenous substances of life, carbohydrates take part in almost all biological processes in vivo. Introducing carbohydrate into the structure of drugs by chemical means, and drugs are earried to the target site through sugar, can change the solubility of compounds and reduce the toxicity. Pyrazole compounds are a class of heterocyclic compounds with widely biologically activity, not only have been widely used in medicine, but also are very important active compounds in pesticides. In order to screen high active, low toxic and environmentally friend new compounds,20glucopyranosylthiourea componds containing a moiety of pyrazole were designed and synthesized, and insecticidal, fungicidal and herbicidal activity of these title componds were evaluated.Firstly, using glucose as starting material,2,3,4,6-tetra-O-acetyl-α-D-bromoglucose were synthesized after acetylation and bromination, then reacted with plumbum thiocyanate to give N-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)isothiocyanate, reacted with hydrazine hydrate to get N-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl) thiosemicarbazide. Then, by the reaction of isothiocyanate glucopyranose and glucopyranosyl thiosemicarbazide with substituted pyrazoles, a series of glucopyranosylthiourea componds containing a moiety of pyrazole were synthesized. Moreover, a series of thiadiazole derivatives containing glucopyranose and pyrazole were prepared by the cyclization of thiourea groups. Finally, all title compounds were confirmed by IR,1H-NMR,13C-NMR and elemental analysis.The herbicidal activity against Brassia campestris and Echinochloa crusgalli was evaluated by plate method. Almost all the title compounds exhibited herbicidal activities against B. campestris at a concentration of100μg/mL. Therein, the inhibitory rates of the compounds4a,4c,4f,6c,6g,6h and7d exceeded70%against the root of B. campestris.The fungicidal activitie against Thanateaphorus cucumeris, Colletotrichum orbiculare and Fusarium gramineaum was evaluated by mycelial growth rate method. Some of these compounds showed a higher inhibitory activity against Thanateaphorus cucumeris at a concentration of100μg/mL. Therein, the inhibitory rates of the compounds6e,6g and6h exceeded50%.The insecticidal activities were evaluated by dipped-leaf method. All title compounds showed little activity against Plutella xylostella(L.) at a concentration of100μg/mL.