NEW MATERIAL:The 2-pyridylmethylthiobenzimidazole derivative of formula I (R is lower alkyl; n is 0, 1 or 2; the substitution site on the pyridine ring is 3 or 4).

EXAMPLE: 2-(3-Pyridylmethylthio)-5-methoxybenzimidazole.

USE: An antiulcer agent and intermediate for pharmaceuticals.

PREPARATION: The compound of formula I wherein n is 0 can be produced by reacting the compound of formula II with the compound of formula III (X is Cl, Br or I) in a solvent such as alcohol in the presence of a basic catalyst such as NaOH at 0W150°C for 10minW72hr.