Synthesis Of The Key Intermediate With Five-Membered Ring Of The Enrecavir

There are more than two billion persons in the world who have infected the heap titis B virus.Hepatitis B is a serious disease,which is infected by the hepatitis B vir us(HBV),and it has been geeat hazard to humans health.Hepatitis B virus is a kind of hepatotropism virus,which mainly exists in the liver cells,damages the liver cells and causing inflammation,necrosis and fibrosis of the liver cells.The human hepatitis B virus(HBV)causes acute and chronic liver infections.In adults,about 90% patients with acute hepatitis can be self-healing.However,chronic hepatitis B is divided intoch ronic hepatitis B carriers,chronic active hepatitis B,hepatitis B cirrhosis and so on.Entecavir is highly specific for against hepatitis B virus.This paper mainly explore the synthetic route of key intermediate with Five-membered Ring of the Enrecavir,4-(tert-Butyl-diphenyl-silanyloxy)-2-trityloxy-phenyl-cyclopentanol.This paper select 3-hydroxylallylene and 3-bromopropene as raw material,by reducing reaction to synthesis 2,5-diene-1-Hexanol,epoxidation reaction to synthesis 5-ene-2,3-epoxy-1-allyl alcohol,substitution reaction to synthesis 2-(propyl-1-ene-2-base)5-hexene1,3-glycol,and cyclization reaction to synthesis of 3-((trityloxy phenyl)methyl)-2-methyl heptyl-1,6-diene-4-ol prepare target compound,by using ~1HNMR and HPLC technology to characterize the structure and purity,and the total yield was 20%.At the same time,explored the reaction for synthesising of some key intermediates,for example,systematic inspected the effects of reaction temperature,time and amount of catalyst on the inte rmediate compound(5)of the synthesis conditions,Optimized and improved the post processing of the intermediate(6).On this basis,through using of the column chromato graphy and gradient elution method,simplifying the posttreatment process to make the over all synthetic route has the advantage of mild reaction conditions,ready available raw materials and the reaction yield is higher and so on.