7-(1-Acetyl-1,2,3,6-tetrahydro-pyridin-4-YL)-9-cyclopropyl-6-fluoro-9H-isothiazolo[5,4-B]quinoline-3,4-dione → 7-(1,2,3,6-Tetrahydro-pyridin-4-YL)-9-cyclopropyl-6-fluoro-9H-isothiazolo[5,4-B]quinoline-3,4-dione

Participants

Reaction Conditions

Reaction Steps

Compound 26 (11.1 mg, 0.028 mmol) is dissolved partially in an aqueous solution of hydrochloric acid (6 M, 3.0 mL) in air and heated at 90° C. to give an amber solution. After 22 h of heating, the solvent is removed under reduced pressure. The residue is dissolved in water (˜3 mL) and titrated to pH 7 with dilute sodium hydroxide. The precipitated solid is collected by filtration, washed with water (2×10 mL), and dried in vacuo to give 27 as a yellow solid (98% purity by HPLC). mp >241-242° C. dec. 1H NMR (DMSO-d6/acetic acid-d4 (5:1 v/v)): δ 1.19 (m, 2H, c-Pr CH2), 1.29 (m, 2H, c-Pr CH2), 2.72 (m, 2H, NCH2CH2), 3.33 (m, 2H, NCH2CH2), 3.54 (m, 1H, c-Pr CH), 3.80 (m, 2H, NCH2CH), 6.21 (m, 1H, NCH2CH), 7.87 (br, 1H, aromatic), 7.91 (br, 1H, aromatic). 19F{1H} NMR (DMSO-d6/acetic acid-d4 (5:1 v/v)): δ −121.4 (s). LCMS m/z calcd for C18H16FN3O2S ([M]+) 357. Found 358 ([M+H]+). HRMS m/z calcd for C18H16FN3NaO2S ([M+Na]+) 380.0845. Found 380.0847.

Provenance & Evidence