Water → HCID 19608701, compound

Participants

Reaction Steps

Ethyl [4-[4-(aminosulfonyl)phenyl]-3-phenylisoxazol-5-yl]propanoate from Step 2 (198 mg, 0.495 mmol) and aqueous sodium hydroxide (10%, 0.30 mL) were dissolved in dioxane (15 mL). The solution was heated to reflux and held for 16 hours. Upon cooling to room temperature, water (20 mL) was added, and the solution was extracted with ether (2×30 mL). The combined ethereal solution was extracted with dilute sodium hydroxide (5%, 2×30 mL). All of the aqueous phases were combined and acidified with hydrochloric acid (conc.) to pH <2. The acidic aqueous phase was extracted with ether (2×30 mL). The final ether solution was dried over magnesium sulfate, filtered and evaporated under reduced pressure to yield a crude solid. Trituration with dichloromethane yielded crystals. The suspension was cooled to 0° C., filtered, washed with hexane and dried to yield [4-[4-(aminosulfonyl)phenyl]-3-phenylisoxazol-5-yl]propanoic acid as a white crystalline solid (135 mg, 73%): mp 207° C. Mass spectrum: MH+=373. Anal. Calc'd. for C18H16N2O5S: C, 58.06; H, 4.33; N, 7.52; S, 8.61. Found: C, 57.87; H, 4.35; N, 7.49; S, 8.54.

Provenance & Evidence