C([O:3][C:4](=[O:33])[CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][O:10][CH2:11][CH2:12][O:13][CH2:14][CH2:15][O:16][CH2:17][CH2:18][O:19][CH2:20][CH2:21][O:22][CH2:23][CH2:24][O:25][CH2:26][CH2:27][O:28][CH2:29][CH2:30][O:31][CH3:32])C>[OH-].[Na+]>[CH3:32][O:31][CH2:30][CH2:29][O:28][CH2:27][CH2:26][O:25][CH2:24][CH2:23][O:22][CH2:21][CH2:20][O:19][CH2:18][CH2:17][O:16][CH2:15][CH2:14][O:13][CH2:12][CH2:11][O:10][CH2:9][CH2:8][CH2:7][CH2:6][CH2:5][C:4]([OH:33])=[O:3]Non-polydispersed ester 21 (0.25 g, 0.46 mmol) was stirred for 18 hours in 0.71 ml of 1 N NaOH. After 18 hours, the mixture was concentrated in vacuo to remove the alcohol and the residue dissolved in a further 10 ml of water. The aqueous solution was acidified to pH 2 with 2 N HCl and the product was extracted into dichloromethane (30 ml×2). The combined organics were then washed with brine (25 ml×2), dried over Na2SO4, filtered and concentrated in vacuo to yield the non-polydispersed title compound as a yellow oil (0.147 g, 62%). FAB MS: m/e 499 (M+H), 521 (M+Na).
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