Study On Synthesis Of Carabrol Ester DEerivatives And Their Antifungal Activities

At present , utilization of natural products as lead compound is an important means of modern drug research. Carabrol isolated from Carpesium macrocephalum Franch. Et Sav. is one of sesquiterpene lactones compounds . Previous research shows thatα-methylene-γ-lactone is its main antibacterial activities group, and structural modification of the bits-4 biochemaical groups can improve the antibacterial activity greatly. According to study in this field, this compound is valuanble to be futher studied. Therefore, on the basis of reserving active groups, this study continued to focuse on the C4 a hydroxyl derivatives ester synthesis. As a result, this paper got 28 kinds of carabrol esters derivatives and determined its biological activities. In order to through studying on structure-activity relationship to provide clues for research and exploration of botanical pesticides, and hope to attain high active compunds to provide cules for biational fungicide. Resluts in this study are as follows:(1)Carabrol as materila, used DCC/DMAP as catalyst system, 28 dericatives were synthesized, their structures were identified with 13CNMR,1HNMR. All of them were ensured to be novel compounds novelty search.(2)Tissue experiment as bioassay method, 28 compounds were tested on the concentration of 2000 mg/L. The result indicates that the difference of compounds activity is greatly, as follows: Compare with the curative effect of carabrone and carabrol to Botrytis cinerea Pers Fr., which were 70.85% and 52.02%, C23 and C24 showed best activity, curative effect were 85.02% and 81.78% individually. However, the curative effect of C21 and C27 were lower, and the curative effect of other compounds considerable to carabrone and carabrol.(3)Through biossay of carabrol and its dericatives, after study on structure-activity relationship and combined with previous findings, found carabrol and its dericatives were sensitive to Botrytis cinerea Pers Fr., and the antibacterial activity of aromatic RACES compounds have great relationship with the groups linked with them. Bioactivity of derivatives was found to have relationship with electron withdrawing and rejecting ablility of substituent on benzene ring. Bioactivity increased when electron density raised, and bioactivity decreased when electron density declined. For futher research, compounds could be synthesized according to this phenomenon to attain higer active compounds.