Study On The Chemical Synthesis Of Halofuginone And Toxicity Of Febrifugine

Cotent: Halofuginone was discovered as alkaloids with excellent biological activity, which come from febrifugine.So it has been used as an antiparasitic feed additive for the prevention of coccidiosis in poultry production and is now undergoing clinical trials for treatment of scleroderma in human. Halofuginone are having highly effective and low toxin at extremely low dosages yet with little side effect. Scientists of medicinal chemistry and pharmacology had pay attention to halofuginone. Raw material was changed in order to the costing of synthesis was cuted down and synthetic condition was mild. This method is widely applicable to the synthesis of halofuginone and derivate. Febrifugine exhibit potent anti-malarial activity. We have made use of ultraviolet spectral luminosity instrument in order to measure the content of febrifugine. Toxicology research of febrifugine made ready to future research.The content in this research thesis contained three parts:1. 7-bromo-6-chloro-4(3H)-quinazolinone is an important intermediate of anticoccidial drug halofuginone, which was prepared from nitrobenzene by bromination, reduction, condensation, cyclization and so on. The overall yield of the seven-step is 60%. carboxylate is an important intermediate of halofuginone,which was prepared from furfuryl amine in a seven-step sequence with yields of 74%.Halofuginone come from condensation,The yield is 58%.raw material is ordinary and synthetic condition is mild.This method is widely applicable to the synthesis of halofuginone and derivate.2.The content of febrifugine.The present work presents a colorimetric method based on the principle that o-aminobenzoic acid is produced by the alkaline hydrolysis of the quinazolone structure of the febrifugine molecule, which can be determined colorimetrically by coupling with N-1-naphthyl ethylene diamine after diazotization.The content of febrifugine determinated by UV spectrophotometer and is 1.36%3. The acute toxicity test showed that the half lethal dose (LD₅₀) of febrifugine in mice is 32.5g/kg. The maximal tolerance dose (MTD) of febrifugine in mice was 65g/kg.In the subacute toxicity test, the febrifugine was intargasrtieally adminiseterd into rats with the dose of 1.63g/kg, 3.25g/kg, 6.5g/kg, which was ended by 14-day. The results showed that there was no remarkable difference in body weight, relative organ weights,hematological indices,serum biochemical parameters and the histopathologic change of main organs between the median dose group or low dose group and the control group. There are few effect of in high dose group.we should made further study.