Synthesis Of Alkaloid A And Its Acetylated Derivatives And Their Protective Effects On Acute Liver Injury

Objective:To synthesize4-hydroxy-2-benzoxazolone and its acetylated derivatives, to determine their purities, and to study their hepatoprotective effects and their related mechanisms.Methods:2-amino-resorcinol was prepared through reduction of2-nitro-resorcinol and then2-amino-resorcinol was reacted with urea to provide HBOA. Compound2was obtained by the reaction of acetyl chloride and HBOA.And then Compound2was reacted with acetyl chloride to produce compound3. The purities of HBOA, AcO-BOA and TC-3were determined by HPLC method.Welchrom-C18(4.6mmx250mm,5μm) was applied,the mobile phase was methanol-water(50:50).The determined wavelength were215nm,215nm and210nm,and the flow rate was1.0ml·min-1.The acute liver injury model was prepared by the intraperitoneal injection of carbon tetrachloride. The liver index,the levels of AST,LDH in serum and levels of MDA, SOD,CAT, GSH and GSH-Px in liver tissue were measured. The expression of TNF-a in liver tissue was investigated by Immexpressionunohistochemistry methods.Results:With2-nitroresorcinol as the starting material, the yeilds of HBOA, AcO-BOA and TC-3were63.08%,68.22%,64.62%respectively. They were all matched with IR,’H-NMR and13C-NMR wave information.In the selected chromatographic conditions,the shapes and separation effects of peaks in HBOA and its acetylated derivatives were well. The purities of HBOA,AcO-BOA and TC-3were99.26%,94.42%,93.73%.CCl4-induced acute liver injury model in mice was established successfully. Compared with control group, the liver index,the levels of AST,LDH,MDA and the expression of TNF-a were increased significantly, the levels of SOD,CAT,GSH and GSH-Px in liver tissue were decreased obviously. Compared with model group, HBOA could decrease the liver index,the levels of serum AST,LDH,MDA in liver tissue and increase the levels of SOD, CAT,GSH,GSH-Px in liver tissue obviously. Immunohistochemical assay showed that HBOA could decrease the expression of TNF-a.Compared with model group, AcO-BOA and TC-3could decrease the liver index,the levels of serum AST,MDA in liver tissue and increase the levels of SOD and GSH in liver tissue significantly. Conclusion:4-hydroxy-2-benzoxazolone and its acetylated derivatives were synthesized and their purities were determined successfully.HBOA, AcO-BOA and TC-3have good hepatoprotective effects for acute liver injury.The mechanisms may be related to attenuating free radical and inhibiting lipid peroxidation and decreasing the outcoming of inflammory factor.