tert-butyl 4-(6-(6-(3-(6-tert-butyl-8-fluoro-1-oxophthalazin-2(1H)-yl)-2-(hydroxymethyl)phenyl)-2-methyl-3-oxo-2,3-dihydropyridazin-4-ylamino)pyridin-3-yl)piperidine-1-carboxylate → 6-tert-butyl-8-fluoro-2-(2-(hydroxymethyl)-3-(1-methyl-6-oxo-5-(5-(piperidin-4-yl)pyridin-2-ylamino)-1,6-dihydropyridazin-3-yl)phenyl)phthalazin-1(2H)-one

Participants

Reaction Steps

tert-butyl 4-(6-(6-(3-(6-tert-butyl-8-fluoro-1-oxophthalazin-2(1H)-yl)-2-(hydroxymethyl)phenyl)-2-methyl-3-oxo-2,3-dihydropyridazin-4-ylamino)pyridin-3-yl)piperidine-1-carboxylate (85 mg, 120 μmol) was deprotected by treatment with 50% trifluoro acid in dichloromethane (10 mL) for 2 hr. The reaction mixture was concentrated to dryness, then partitioned between ethyl acetate and saturated sodium bicarbonate. The organic phase was dried over sodium sulfate, filtered and concentrated. The resulting crude product was further purified by crystallization from hot isopropylacetate/hexanes. A crystalline product was collected by filtration, providing the desired product as a white solid (48 mg, 65.7%). (M+H)+=610 m/e. 1H NMR (300 MHz, CHLOROFORM-d) δ: 8.63 (s, 1H), 8.27-8.33 (m, 2H), 8.21 (d, J=2.0 Hz, 1H), 7.44-7.72 (m, 6H), 6.94 (d, J=8.5 Hz, 1H), 4.46 (s, 2H), 3.88-3.96 (m, 3H), 3.35-3.44 (m, 2H), 2.85-2.99 (m, 2H), 2.65-2.78 (m, 1H), 1.83-1.97 (m, 4H), 1.43 (s, 9H).

Provenance & Evidence