Sodium Hydroxide → 4-Ethyl-1-[4-[2-(ethylcarbamoylamino)-7-(2-pyridyl)-1,3-benzothiazol-5-yl]thiazol-2-yl]piperidine-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of ethyl 4-ethyl-1-[4-[2-(ethylcarbamoylamino)-7-(2-pyridyl)-1,3-benzothiazol-5-yl]thiazol-2-yl]piperidine-4-carboxylate (20 mg, 0.035 mmol) in EtOH (1 mL) was added aqueous NaOH (0.3 mL, 3.5 M). The solution was heated to 70° C. for 22 h then cooled to rt and the pH of the solution adjusted to 4-5. The mixture was extracted with EtOAc (3×1 mL) and the combined organic layer combined, dried over Na2SO4, filtered then evaporated under reduced pressure. The residue was adsorbed to a 0.5 g silica plug then purified using a 4 g silica column and a MeOH:DCM elution gradient. Compound 209 was isolated as an off-white solid (3.4 mg, 18% yield). 1H NMR (MeOD) δ 8.75 (ddd, J=4.8, 1.8, 0.9 Hz, 1H), 8.38 (d, J=1.5 Hz, 1H), 8.22 (d, J=8.2 Hz, 1H), 8.18 (d, J=1.4 Hz, 1H), 7.97-7.91 (m, 1H), 7.37 (ddd, J=7.5, 4.9, 0.9 Hz, 1H), 7.16 (s, 1H), 3.95 (dt, J=13.1, 3.7 Hz, 2H), 3.36 (t, J=7.2 Hz, 2H), 3.25 (td, J=13.3, 2.9 Hz, 2H), 2.24 (d, J=13.2 Hz, 2H), 1.70-1.53 (m, 4H), 1.24 (td, J=7.2, 2.0 Hz, 3H), 0.92 (td, J=7.5, 4.2 Hz, 3H). MS: 537.12 [M+H]+.

Provenance & Evidence