Hydrochloric Acid → Swainsonine

Participants

Reaction Steps

To a solution of swainsonine acetonide (104 mg, 0.49 mmol) in THF (6.5 ml) was added 6.0 ml of 6M HCl. The colorless solution was stirred overnight at room temperature. The solvent was removed in vacuo, leaving a colorless, viscous oil. The oil was then purified by an ion exchange chromatography (Dowex1X8). Fractions (visualized with iodine or ninhydrin) were collected and concentrated in vacuo to furnish 68.5 mg(81% yield) of swainsonine as a white solid: mp and mixed mp 140-142 C; [ ]D25 =-75.71 (c 2.33, MeOH); Rf=0.36 in 1-butanol:chloroform:ethanol:concentrated ammonium hydroxide (4:4:4:1); 1H NMR (D2O, ref. DSS, 300MHz) 4.34 (m, 1H, H-2), 4.24 (dd, J1,8a =3.7 Hz, J 6.1 Hz, 1H, H-1), 3.78 (ddd, J=3.9, 9.3 & 10.7 Hz, 1H, H-8), 2.89 (m, 1H), 2.86 (dd, J= 2.6 & 11.0 Hz, 1H, H-3), 2.53 (dd, J=7.8 & 11.0 Hz, 1H, H-31), 2.04 (m, 1H), 1.96 (m, 1H), 1.89 (dd, J8a,8 =9.3 Hz, J8a,l =3.7 Hz, H-8a), 1.70 (m, 1H), 1.49 (m, 1H), 1.22 (m, 1H); 13C NMR (D2O, ref: CH3CN, 100MHz) δ23.21, 32.51, 51.72, 60.65, 66.37, 69.08, 69.72, 72.87; HRMS(M+) 173.1052 calcd for C8H15NO3, found 173.1041.

Provenance & Evidence