NOVELTY - Synthesis of dabigatran etexilate involves mixing cyano-substituted benzene compound (II) with thionyl chloride, refluxing, vacuum-distilling and dissolving residue in organic solvent; adding amino-substituted benzene-containing pyridine derivative (I) and organic alkali, stirring, washing, concentrating organic phase and purifying; dissolving in alcohol, adding sodium alkoxide, refluxing, cooling, adding ammonium salt, mixing, filtering and purifying; and dissolving in solvent, dropping imidazole derivative, stirring, washing organic layer, drying, vacuum-concentrating and purifying.    USE - Method for synthesizing dabigatran etexilate (claimed).    ADVANTAGE - The method has simple and easy operation. It has total yield increase of 36.6-54.8%.    DETAILED DESCRIPTION - Synthesis of dabigatran etexilate comprises:    (A) mixing cyano-substituted benzene compound of formula (II) with thionyl chloride in dimethylformamide at room temperature, refluxing under nitrogen protection for 2-4 hours, vacuum-distilling and dissolving residue in organic solvent;    (B) adding amino-substituted benzene-containing pyridine derivative of formula (I) at 0-5 degrees C, slowly adding organic alkali, stirring overnight, washing with water, concentrating organic phase and purifying by silica gel column chromatography to obtain cyano-substituted benzene-containing benzimidazole derivative of formula (III);    (C) dissolving compound (III) in alcohol, adding sodium alkoxide, heating and refluxing overnight, cooling to room temperature, adding ammonium salt, mixing at room temperature for 24-36 hours, filtering and purifying by silica gel column chromatography to obtain tri-amino-substituted benzene-containing benzimidazole derivative of formula (IV); and    (D) dissolving in solvent, dropping imidazole derivative of formula (V) at 0-5 degrees C, stirring for 30 minutes, adding bi-acid/bi-ester, stirring for 5 minutes, standing, removing aqueous layer, washing organic layer with water for 2-4 times, drying, vacuum-concentrating and purifying by silica gel column chromatography.