Hydrochloric Acid → 4-amino-6-(1,1-dioxido-4H-1,2,4-benzothiadiazin-3-yl)-7-hydroxythieno[3,2-b]pyridin-5(4H)-one

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Reaction Conditions

Reaction Steps

The product of Example 268C (2.29 g, 6.69 mmol) was reacted with 2-aminobenzenesulfonamide (1.15 g, 6.69 mmol) in toluene (60 mL), and stirred at reflux for 5 hours. The reaction was cooled to 25° C. and the resulting precipitate was collected by filtration and dried (1.95 g, 62%). The resulting solid (1.95 g, 4.2 mmol) was reacted with 10% aqueous KOH (60 mL) at reflux for 24 hours, cooled to 25° C. and acidified with concentrated hydrochloric acid to pH 2. The resulting solid was collected by filtration, washed repeatedly with water and dried to provide the title compound (1.5 g, 98%).(Any sodium salt made?) 1H NMR (300 MHz, DMSO-d6) δ ppm 6.12 (s, 2 H) 7.49 (d, J=5.52 Hz, 1 H) 7.57 (m, 2 H) 7.79 (t, J=7.17 Hz, 1 H) 7.93 (d, J=7.72 Hz, 1 H) 8.34 (d, J=5.52 Hz, 1 H) 14.33 (s, 1 H) 14.68 (s, 1 H).

Provenance & Evidence