Hydrochlorothiazide → 6-Chloro-2-(2-hydroxyethyl)-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide

Participants

Reaction Steps

To a solution of hydrochlorothiazide (ONBIO, Inc., Ontario, Canada) (13.82 g, 46.4 mmol) in DMF (50 mL) was added cesium carbonate (7.51 g, 23.0 mmol) and ethyl bromoacetate (7.69 g, 46.1 mmol) and the mixture was stirred for 18 hours at room temperature. The solids were removed via suction filtration, and the solvent was evaporated under vacuum. The resulting residue was partitioned between ethyl acetate and water, and the organic layer was washed with water and brine, and dried over magnesium sulfate. After evaporation of the solvent, the residue was recrystallized from ethyl acetate/ether to give the title product (10.9 g, 61% yield) as white needles: mp 199-203° C.; 1H NMR (400 MHz, d6-DMSO) δ 8.07 (s, 1H), 8.01 (s, 1H), 7.53 (s, 2H), 7.08 (s, 1H), 4.97 (s, 2H), 4.14 (q, J=7.1 Hz, 2H), 3.82 (s, 2H), 1.19 (t, J=7.1 Hz, 3H); Mass spectrum (API-TIS) m/z 384 (MH+), 401 (MNH4+), 784 (2MNH4+).

Provenance & Evidence