The present invention provides an SSAO inhibitor and an application thereof in preparing a drug for treating a disease related to SSAO. In particular, the present invention provides a compound shown in formula (IV) and a pharmaceutically acceptable salt thereof.

##STR00001##

Provided is a preparation method for revaprazan hydrochloride, the method comprising: (1) the preparation of 4-hydroxyl-2-(4-fluoroaniline)-5,6-dimethylpyrimidine; (2) the preparation of 4-chloro-2-(4-fluoroaniline)-5,6-dimethylpyrimidine; (3) the preparation of revaprazan hydrochloride. The method has advantages such as simple operations, high product purity, good yield and suitability for industrial production.

Provided is a preparation method for revaprazan hydrochloride, the method comprising: (1) the preparation of 4-hydroxyl-2-(4-fluoroaniline)-5,6-dimethylpyrimidine; (2) the preparation of 4-chloro-2-(4-fluoroaniline)-5,6-dimethylpyrimidine; (3) the preparation of revaprazan hydrochloride. The method has advantages such as simple operations, high product purity, good yield and suitability for industrial production.