The Synthesis And Anti-Live Fibrosis Activity Of Betulin Derviatives

Betulin is a pentacyclic triterpene compound widely distributed in nature.It has many pharmacological activities such as anti-inflammatory,anti-viral,anti-tumor and anti-oxidation.Due to the poor solubility of birch ester alcohol and low utilization in vivo,it is of great significance to modify the structure of birch ester alcohol.In this paper,studies on the structure modification of birch ester alcohol,the derivatives of C-28 of birch ester alcohol and the anti-fibrotic activity of beryllyl alcohol 30-C oxidation products were studied.In the modification of bicyclic esterification of betulin C-28,the main use of betulin ester C-3 is secondary alcohol and C-28 is primary alcohol and the difference in reactivity directly structurally modified the C-28 position,using Chlorophenyl chloroformate,a highly reactive esterification reagent,selectively produces a C-28 modified product as an interrmediate product,and is further derivatized according to its leaving activity to introduce a functional group.A series of derivatives of betulin C-28.Subsequently,the apoptosis of LX-2 cells was investigated with the four compounds B-1,B-2,B-3 and B-4.The results of single staining with PI showed that all four compounds could induce apoptosis of LX-2 cells,and the results of mitochondrial membrane potential assay in rhodamine showed that all four compounds effectively induced depolarization of mitochondrial membrane potential in LX-2 cells.B-3 with the introduction of antioxidant groups and the B-4 introduction of mitochondrial targeting groups induce a strong mitochondrial membrane potential depolarization in LX-2 cells.Betulin ester C-28 position derivative shows its anti-hepatic fibrosis activity by inducing apoptosis of LX-2.In the modification of the C-30 position of birch ester alcohol,first the methyl group at the C-30 position was oxidized to an aldehyde group and further oxidized to a carboxyl group to give a series of derivatives of betulin C-30.Subsequently,the effects of B-5,B-6,B-7,B-8 and B-9 on the proliferation activity of mouse macrophage Raw264.7 cells were examined by CCK-8 experiments.The results showed that the above compounds significantly inhibited the proliferation of Raw264.7 cells with IC50 values of 155,383,43,32,and 71 μM,respectively.The NO content in Raw264.7 was determined by flow cytometry.The results showed that the synthesized compounds had an inhibitory effect on NO production induced by LPS cells.At the same time,by means of confocal imaging,it was found that the compounds all inhibited the production of ROS induced by LPS.Subsequently,the effect of the compound on the content of IL-la and IL-1β in Raw264.7 was detected by ELISA.The data showed that the compounds had inhibitory effects on the expression of IL-la and IL-1β in Raw264.7,and the inhibitory effect of B-9 on IL-1βwas especially obvious,which was more than 10 times higher than that of the control group.Finally,the effect of five compounds on the expression of Caspase3 and Bax/Bcl-2 protein was examined by western blot.The results showed that the five compounds can inhibit the expression of the two proteins.It can be used as a potential anti-hepatic fibrosis agent.