Oligosaccharide compound inhibiting endogenous factor X enzyme activity and pharmaceutical composition thereof

The invention discloses an oligosaccharide compound having a pure chemical structure and inhibiting an endogenous coagulation factor X enzyme and a preparation method thereof, a pharmaceutical composition containing the oligosaccharide compound and an application of the oligosaccharide compound and the pharmaceutical composition in prevention and/or treatment of thrombotic diseases. The oligosaccharide compound is an oligosaccharide composed of L-2,4-disulfate fucose, D-glucuronic acid, D-2-deoxy-2-acetamido-4,6-disulfate-galactose, 2,5-dehydrated talose or sugar alcohol thereof, and sugar amine and having the structure represented by the formula (I), wherein in the formula (I), n is 0, 1, 2, 3, 4, 5 or 6; and R is optionally selected from -CH=O, -CH(OH)2, -CH2OH, -CH2NH2, -CH2NHR' or -CH2N(R')2, and R' is a substituted or unsubstituted C1-C6 straight-chain or branched-chain alkyl, or substituted or unsubstituted C7-C12 aryl.