Aluminium lithium hydride → 7-(4-methoxybenzyl)-4-hydroxy-3-(hydroxymethyl)-1,7-naphthyridin-8(7H)-one

Ethyl 7-(4-methoxybenzyl)-4-hydroxy-8-oxo-7,8-dihydro-1,7-naphthyridine-3-carboxylate (4.00 g, 11 mmol) was suspended in anhydrous THF (60 ml) and the mixture was cooled down to −10° C. Lithium aluminum hydride 2M in THF (11 ml, 23 mmol) was added dropwise to the mixture. The cold bath was then removed and the reaction was stirred for two hours at room temperature. Sodium sulfate decahydrate (10 g) was added portionwise to the reaction. The mixture was stirred for 3 hours and then filtered. The cake collected in the filter funnel was extracted for 12 hours in a soxhlet apparatus in a 2:1 mixture of chloroform and methanol. The filtrate was directly loaded unto silica gel and purified by column chromatography on silica gel using a gradient of 0 to 10% metahnol in DCM to give 7-(4-methoxybenzyl)-4-hydroxy-3-(hydroxymethyl)-1,7-naphthyridin-8(7H)-one (1.3 g, 37% yield) as light yellow solid. MS(M+H)+ 313.