Sodium Hydroxide → 2-[4-(5-fluorobenzothiazol-2-yl]methyl-3,4-dihydro-3-oxo-2H-1,4-benzothiazin-2-yl]acetic acid

Participants

Reaction Steps

The compound of Example 1 (275 mg) was dissolved in methanol-dioxane (1:2, v/v, 3 ml), and 0.7 ml of 2N sodium hydroxide solution was added dropwise to the solution with stirring at room temperature. The mixture was stirred for further 90 minutes. The solvent was distilled off and the residue was diluted with water, then the aqueous mixture was acidified with 10% hydrochloric acid. The precipitated solid was crystallized from chloroform-hexane to give 196 mg of the title compound. The structural formula and physical data of this compound are shown in Table 25.

Provenance & Evidence