4-Methylmorpholine → (3R,4S,5S)-tert-butyl 4-((S)-2-((((9H-fluoren-9-yl)methoxy)carbonyl)amino)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoate

To a mixture of N-[(9H-fluoren-9-ylmethoxy)carbonyl]-L-valine (18.53 g, 54.60 mmol, 1.3 eq.) and 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) (9.58 g, 54.6 mmol, 1.3 eq.) in 2-methyltetrahydrofuran (118.00 mL, 0.34 M) was added N-methylmorpholine (6.52 mL, 59.1 mmol, 1.5 eq.) followed by #4 (11.80 g, 39.9 mmol, 1 eq.). After 3 hours, the reaction was quenched with water (50 mL) and stirred for 15 minutes. The aqueous layer was separated and back-extracted with 2-methyltetrahydrofuran (50 mL). The combined organic layers were washed with saturated aqueous sodium bicarbonate solution (50 mL), dried over magnesium sulfate, filtered, and concentrated in vacuo to give a colorless oil, which was purified by silica gel chromatography (Gradient: 5% to 40% ethyl acetate in heptane) to give #5 (26.2 g, 91%) as a colorless foam. LC-MS (Protocol I) m/z 581.3 [M+H+] 1604.3 [M+Na+], retention time=4.993 minutes; 1H NMR (400 MHz, DMSO-d6), possibly a mixture of rotamers, characteristic major signals: δ 7.88 (d, J=7.4 Hz, 2H), 7.71 (d, J=7.4 Hz, 2H), 7.62 (d, J=8.6 Hz, 1H), 7.41 (dd, J=7.4, 7.4 Hz, 2H), 7.27-7.34 (m, 2H), 4.13-4.32 (m, 4H), 3.70-3.82 (br m, 1H), 3.24 (s, 3H), 2.92 (br s, 3H), 2.54 (dd, J=15.7, 2.4 Hz, 1H), 2.17 (dd, J=15.4, 9.4 Hz, 1H), 1.95-2.07 (m, 1H), 1.70-1.83 (br m, 1H), 1.40 (s, 9H), 0.83-0.94 (m, 9H), 0.69 (t, J=7.2 Hz, 3H).

1. customthe reaction was quenched with water (50 mL)
2. customThe aqueous layer was separated
3. extractionback-extracted with 2-methyltetrahydrofuran (50 mL)
4. washThe combined organic layers were washed with saturated aqueous sodium bicarbonate solution (50 mL)
5. dry with materialdried over magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customto give a colorless oil, which
9. customwas purified by silica gel chromatography (Gradient: 5% to 40% ethyl acetate in heptane)

ORDレコード

ord-6880f5f967504a58b794a36642235c7d

出典データセット

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08828401B2