TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The process (P1) optionally involves isolation of hydrochloride salt of prazole sulfides using organic solvent prior to oxidation. The condensing step (b) may optionally, be conducted in presence of water miscible or water immiscible organic solvent. The reaction is carried out at 30-85 degrees C. Preferred Components: The 2-hydroxymethyl pyridine hydrochloride is selected from 2-hydroxymethyl-3,5-dimethyl-4-methoxy pyridine hydrochloride, 2-hydroxymethyl-3-methyl-4-methoxy pyridine hydrochloride, 2-hydroxymethyl-3-methyl-4-(2,2,2-triflouromethoxy) pyridine hydrochloride, 2-hydroxymethyl-3,5-dimehyl-4-chloro pyridine hydrochloride, 2-hydroxy methyl-3,5-dimethyl-4-nitro pyridine hydrochloride; 2-hydroxymethyl-3,4-dimethoxy pyridine hydrochloride, 2-hydroxymethyl-4-nitro-3-methyl pyridine hydrochloride and 2-hydroxymethyl-4-chloro-3-methoxy pyridine hydrochloride. The substituted benzimidazole compound is selected from 5-furanyl-2-mercapto benzimidazole; 2-mercapto-1H-benzimidazole and 5-diflouromethoxy 2-mercapto benzimidazole. The prazole sulfide/precursor is selected from 2-(((4-methoxy-3-methyl)-2-pyridinyl)methylthio)-5(1H-pyrrol-1-yl)benzimidazole; 2(((4-(2,2,2-triflouroethoxy)-3-methyl-2-pyridinyl)methyl)thio)-1H-benzimidazole; 5-methoxy-2-(((4-methoxy-3,5-dimethyl-2-pyridinyl)-methyl)thio)-1H-benzimidazole; 5-methoxy-2-(((4-chloro-3,5-dimethyl-2-pyridinyl)-methyl)thio)-1H-benzimidazole; 5-methoxy-2-(((4-nitro-3,5-dimethyl-2-pyridinyl)-methyl)thio)-1H-benzimidazole; 2(((4-chloro-3-methyl-2-pyridinyl)methyl)thio)-1H-benzimidazole; 2(((4-nitro-3-methyl-2-pyridinyl) methyl)thio)-1H-benzimidazole; 5-diflouromethoxy-2-((3,4-dimethoxy-2-pyridinyl)-methylthio)-1H-benzimidazole and 5-diflouromethoxy-2-((3-methyl-4-chloro-2-pyridinyl)-methylthio)-1H-benzimidazole and their hydrochlorides. The oxidizing agent is sodium hypochlorite. The organic solvent (s2) is ether (preferably tetrahydrofuran (THF)). ACTIVITY - Gastrointestinal-Gen.. No biological data is given.    MECHANISM OF ACTION - Proton pump inhibitor.    SPECIFIC COMPOUNDS - Preparation of 6 compounds is specified as (I) e.g. 2-((((3-methoxypropoxy)-3-methyl)-2-pyridinyl)methylsulfinyl)-1H-benzimidazole (rabeprazole) (Ia); 5-methoxy-2-(((4-methoxy-3,5-dimethyl-2-pidinyl)methylsulfinyl)-1H-benzimidazole (omeprazole); 2-(((4(2,2,2-triflouroethoxy)-3-methyl)-2-pyridinylm)ethyl sulfinyl)-1H-benzimidazole (lansoprazole); pantoprazole; and tenatoprazole.    EXAMPLE - 25 g of 2-hydroxymethyl-3-methyl-4-(3-methoxypropoxy)pyridine hydrochloride was suspended in 250 ml of toluene and cooled to 0 degrees C. Then 21.25 g of thionyl chloride was added at 0-5 degrees C and maintained for 1 hour at the same temperature. Then temperature was slowly raised to 30 degrees C in 1 hour. The excess thionyl chloride was expelled under vacuum at 30 degrees C for 2 hours and the reaction mass was cooled to 0 degrees C, 50 ml water was slowly added at 10 degrees C. To the aqueous layer was charged 15.25 g of 2-mercapto benzimidazole at room temperature (RT), stirred at RT for 3-4 hours, and the pH was adjusted with 10% of caustic lye solution to 7-7.5 at 0-5 degrees C; and then was charged 50 ml of tetrahydrofuran and 3.38% sodium hypochlorite (237.3 g) at 0-5 degrees C, which was maintained for 1 hour. pH was adjusted to 7-7.5 with acetic acid at 0-5 degrees C, which was maintained for 1-2 hour. The mixture was stirred for freeness then methylene dichloride (MDC) was charged to reaction mass and then MDC layer and aqueous layer were separated. MDC layer was distilled under vacuum to obtain 2-((((3-methoxypropoxy)-3-methyl)-2-pyridinyl)methylsulfinyl)-1H-benzimidazole (rabeprazole), yield 22.5 g (dry weight).