Sodium Chloride → tert-butyl N-[(3S,7S,8R,9S)-7-benzyl-8-hydroxy-9-methyl-2-oxo-1,5-dioxonan-3-yl]-N-tert-butoxycarbonylcarbamate

To a solution of tert-butyl N-[(3S,7S,8R,9S)-7-benzyl-9-methyl-2-oxo-8-triisopropylsilyloxy-1,5-dioxonan-3-yl]-N-tert-butoxycarbonylcarbamate (5.77 g, 9.07 mmol, 1.00 equiv) in THF (91 ml) was added tetrabutylammonium fluoride (TBAF; 1M in THF, 18 ml, 18 mmol, 2.0 equiv). The resulting solution was stirred at room temperature for 1.5 h, poured into 100 mL sat'd sodium chloride (NaCl), extracted with EtOAc (3×100 mL). The combined organic extracts were dried over MgSO4, filtered, and concentrated to provide an oil. Purification by automated silica gel column chromatography provided tert-butyl N-[(3S,7S,8R,9S)-7-benzyl-8-hydroxy-9-methyl-2-oxo-1,5-dioxonan-3-yl]-N-tert-butoxycarbonylcarbamate (3.15 g, 72.4%) as a solid white foam: IR (ATR) 3489, 2980, 2934, 1740, 1703, 1496, 1476, 1454, 1393, 1367, 1307, 1254, 1210, 1168, 1145, 1121, 1041, 909, 850, 729, 701 cm−1; 1H NMR (400 MHz, CDCl3) δ 7.31-7.27 (m, 2H), 7.23-7.16 (m, 3H), 5.21 (dd, J=8.8, 4.8 Hz, 1H), 5.06-4.91 (m, 1H), 4.16 (dd, J=12.1, 4.8 Hz, 1H), 3.89 (dd, J=12.1, 8.8 Hz, 1H), 3.77 (d, J=9.9 Hz, 1H), 3.55-3.42 (m, 2H), 3.00 (dd, J=13.8, 5.0 Hz, 1H), 2.57 (dd, J=13.8, 9.4 Hz, 1H), 2.26 (d, J=7.8 Hz, 1H), 2.10 (s, 1H), 1.50 (s, 18H), 1.47 (d, J=6.5 Hz, 3H); 13C NMR (101 MHz, CDCl3) δ 169.75, 152.71, 139.53, 129.10, 128.49, 126.28, 83.15, 77.20, 76.51, 71.67, 57.69, 47.63, 36.34, 27.95, 18.58; HRMS-ESI (m/z) [M+Na]+ calc'd for C25H37NNaO8; 502.2411 found 502.2418.

1. extractionextracted with EtOAc (3×100 mL)
2. dry with materialThe combined organic extracts were dried over MgSO4
3. filtrationfiltered
4. concentrationconcentrated
5. customto provide an oil
6. customPurification by automated silica gel column chromatography

ORDレコード

ord-58917976a21a4238944bc56cfa2c66fc

出典データセット

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08835462B2