Synthesis And Antifungal Activity Of Hydronopyl Acetals And Hydronopic Acidamides

Nopol is the product of ?-pinene and paraformaldehyde by Prins reaction.Hydronopol can be synthesized by hydrogenation of nopol in the presence of catalytic.Many studies have shown that nopol derivatives have varying degrees of sterilization and deworming effect.The most commonly used fungicide also has shortcomings in environment and resistance.Terpenoids botanical fungicides have good antifungal activity,and can better alleviate such problems.In this paper,16 derivatives were synthesized by the reaction of oxidation,condensation and substitution,while hydronopol was the starting material.The 16 derivatives included hydronopyl aldehydes,3 acetals hydronopyl,hydronopic acid,hydronopic acyl chloride and 10 hydronopic acidamide.13 compounds were novel compounds which were not reported.All the compounds were separated and purified by vacuum distillation and recrystallization,and characterized by IR,MS and NMR.Among this article,15% triadimefon as a positive control.Rhizocitonia solani,Phytophthora capsici,Colletotrichum gloeosporioide,Cdletotrichum gloeosporioides,Magnaporthe grisea as tested strains.The inhibition ratios of 13 compounds to five plant pathogens were determined by the growth rate method.The experimental data was analyzed by DPS and SPSS software in order to obtain the inhibition concentration and independent regression equation of the compounds.The preliminary antifungal activity results showed that the compounds had different inhibition ratio to 5 plant pathogens.With the increasing concentration of the compounds,the inhibitory effect also increased.Acetal compounds had better antifungal activity than amide compounds.Most compounds exhibited 90% good inhibition ratio at concentration of 500mg/L.When the concentration was reduced to 31.25mg/L,inhibition ratios of hydronopyl aldehyde 1,2-ethandiol acetal to Colletotrichum gloeosporioides,Rhizocitonia solani and Phytophthora capsici were 70.69%,68.33% and 52.14%.The inhibition ratios were quite to triadimefon at the concentration of 30 mg/L.N-o-hydroxyphenyl-hydronopic had high inhibition ratio to Cdletotrichum gloeosporioides and Magnaporthe grisea which were 36.05% and 50%.Other comounds didn't show good antifungal activities.EC50 results showed as fowllows,the EC50 of hydronopyl aldehyde 1,2-propanediol acetal to Colletotrichum gloeosporioides was 8.2224mg/L,which was lower than triadimefon.Also,hydronopyl aldehyde 1,2-propanediol acetal demonstrated the most powerful antifungal capacity against Rhizocitonia solani and the EC50 was 35.87mg/L,which was quite equal to triadimefon.These two compounds had better antibacterial activity.The EC50 of the N-i-propyl-hydronopic acidamide,hydronopyl aldehyde 1,3-propanediol acetal,N-o-hydroxyphenylhydronopic acidamide against Phytophthora capsici,Cdletotrichum gloeosporioides,Magnaporthe grisea were 39.0802mg/L,113.1214mg/L and 40.9962mg/L.These EC50 values were far higher than triadimefon and had poor antibacterial effect.