New water soluble benzimidazoles with a high degree of stability, which are substituted at the 1-position with carboxyalkoxycarbonyl substituents and at the 2-position with a 4-thiazolyl group are effective fungicides and anthelmintics. The compounds as well as processes for their preparation are described along with antifungal and anthelmintic compositions for their use. The 1-position substituent is a carboxyalkoxycarbonyl group of from 3 to 11 carbon atoms including certain salts and derivatives of the carboxy group. The compounds are generally prepared by contacting a 1-unsubstituted benzimidazole with a protected carboxyalkoxycarbonyl chloride.