The Synthesis Of Galactosyl Liver Targeting Drug Carrier

Hepatic diseases,especially liver cancer,threaten human's live gravely.The morbidity and mortality of which is higher and higher recently.There are very few opportunities to kill cancer cells because of the low efficacy of anti-cancer drug,and the other weakness is that few carriers could send the drug into the cancer cells.Drug is not targeting,but hepatic targeting drugs carrier can be.It is able to transport anti-cancer drug to the right location and make it to be collected.Besides that,reducing the dose and times,diminishing adverse drug reaction are the advantages of hepatocyte-selective drug delivery system.We started with galactose to synthesis three kinds of galactosyl intermediates: 1,2,3,4,6-penta-O-acetyl-galactopyranose,2,3,4,6-tetra-O-acetyl-galactopyranosyl bromide and 2,3,4,6-tetraacetyl-1-(2-bromoethyl)galactopyranoside in different methods.The reaction conditions and mechanisms of different intermediates are analyzed.The optimal conditions of synthesizing of 1,2,3,4,6-penta-O-acetyl-galactopyranose is 115?~120?,1.5 h.Reatced for 20 h at room temperature away from light is the best conditions for the synthesis of 2,3,4,6-tetra-O-acetyl-galactopyranosyl bromide.And the preferential method of the synthesis of 2,3,4,6-tetraacetyl-1-(2-bromoethyl)galactopyranoside is BF3OEt2 catalyst.Diethylenetriaminepentaacetic acid(DTPA)is a common medical nuclear magnetic contrast agent with five carboxyl groups in the molecule,which have certain hydrophil ic properties.DTPA reacted with 2,3,4,6-tetra-O-acetyl-galactopyranosyl bromide,2,3,4,6-tetraacetyl-1-(2-bromoethyl)galactopyranoside and long chain amines to synthe size series of DTPA-bisamides,galactosyl,DTPA-bisamides,dodecyl galactosamine,gal actosyl DTPA-dodecylamide.The structures were characterized by MS.And we discus sed the reaction conditions in order to provide guidance for the synthesis of liver targ eting contrast agent dual functional drug carrier.