反应详情

Ethyl-8-chloro-1-[4-(1H-pyrazolo-1-yl)benzyl]-4-thioxo-1,4-dihydrocinnoline-3-carboxylate [(Example 60, Step 4) 188 mg, 0.442 mmol] was dissolved in 1,2-dimethoxyethane (1.5 mL) and treated with a mixture of (±)-trans-3-hydrazinotetrahydro-2H-pyran-4-ol and (±)-trans-4-hydrazinotetrahydro-2H-pyran-3-ol (117 mg, 0.885 mmol, 2 equiv) and potassium carbonate (183 mg, 1.327 mmol, 3 equiv). The mixture was placed into an oil bath preheated to 90° C. for 35 minutes, cooled to ambient temperature, diluted with water and extracted with ethyl acetate (3×50 mL). The combined organic extracts were washed once with brine, dried with sodium sulfate; filtered and concentrated in vacuo. The residue was purified by silica gel gradient chromatography (100:0 to 0:100; hexanes:ethyl acetate), providing an inseparable mixture of regioisomers, which was further purified by chiral HPLC (Chiralcel OJ Column, 100% methanol) to produce a first-, second-, and third-eluting peak. The first-eluting peak was determined to the titled compound (enantiopure, relative trans stereochemical configuration), of which the absolute stereochemistry is unknown: 1H-NMR (400 MHz, CDCl3) δ 8.22 (1H, d, J=8.1 Hz), 7.87 (1H, s), 7.71-7.59 (4H, m), 7.46 (1H, t, J=8.1 Hz), 7.29-7.20 (2H, m), 6.44 (1H, s), 6.33 (2H, s), 4.52-4.43 (1H, m), 4.26-4.17 (2H, m), 4.11-4.04 (1H, m), 3.55 (1H, t, J=12.0 Hz), 3.32 (1H, t, J=10.3 Hz), 2.32-2.19 (1H, m), 2.14-2.06 (1H, br d J=12.4 Hz). ppm; low resolution mass spectrometry (ES+) m/z 477.3 [(M+H)+; calculated for C24H22ClN6O3: 477.5].

1. customThe mixture was placed into an oil bath
2. extractionextracted with ethyl acetate (3×50 mL)
3. washThe combined organic extracts were washed once with brine
4. dry with materialdried with sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue was purified by silica gel gradient chromatography (100:0 to 0:100; hexanes:ethyl acetate)
8. customproviding
9. additionan inseparable mixture of regioisomers, which
10. customwas further purified by chiral HPLC (Chiralcel OJ Column, 100% methanol)
11. customto produce a first-, second-, and
12. washthird-eluting peak