Cesium carbonate → (+/-)-4-(5-cyanobenzo[d]oxazol-2-yl)-4-(5-methoxy-7-methyl-1H-indol-4-yl)pentanoic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of (±)-tert-Butyl 4-(2-(5-cyanobenzo[d]oxazol-2-yl)-5-methoxy-5-oxopentan-2-yl)-5-methoxy-7-methyl-1H-indole-1-carboxylate (Example 150-B) (83 mg, 0.160 mmol) and cesium carbonate (261 mg, 0.802 mmol) in MeOH (1.6 mL) was heated to 60° C. and stirred for 2 hrs. The reaction was cooled down to rt and quenched with a saturated solution of ammonium chloride, MeOH was then removed in vacuo. The residue was diluted with AcOEt and water. The layers were separated and the water layer was extracted with AcOEt. The combined organic layers were passed through a phase separator and purified by preparative HPLC (HC-B) to provide the title compound. 1H NMR (400 MHz, DMSO-d6) δ ppm 11.05 (br. s., 1H) 8.32 (d, J=1.26 Hz, 1H) 7.66-7.89 (m, 2H) 7.30 (t, J=2.91 Hz, 1H) 6.69 (s, 1H) 6.38 (dd, J=3.03, 1.77 Hz, 1H) 3.51 (s, 3H) 2.58-2.65 (m, 2H) 2.44 (s, 3H) 2.15 (dd, J=9.73, 6.69 Hz, 2H) 1.91 (s, 3H). HRMS calcd. for C23H21N3O4 (M+H)+ 404.1610. found 404.1607.

Provenance & Evidence