[OH:1][CH:2]([CH2:14][CH2:15][CH2:16][C:17]1[CH:18]=[N:19][CH:20]=[CH:21][CH:22]=1)[CH2:3][CH2:4][CH2:5][CH2:6][O:7]C1CCCCO1.CC(C)([O-])C.[K+].Br[CH2:30][C:31]([O-:33])=[O:32].[Na+]>CN(C)C=O.O1CCCC1.CCOCC.O>[OH:7][CH2:6][CH2:5][CH2:4][CH2:3][CH:2]([CH2:14][CH2:15][CH2:16][C:17]1[CH:18]=[N:19][CH:20]=[CH:21][CH:22]=1)[O:1][CH2:30][C:31]([OH:33])=[O:32]To a solution of 4.17 g (13.8 mmol) of 5-hydroxy-8-(3-pyridyl)-1-(2-tetrahydropyranyloxy)-octane (example 37) in 30 ml dry dimethylformamide is added 17 ml (27.6 mmol) of a 1.61M solution of potassium t-butoxide in tetrahydrofuran and the resulting red solution is stirred for 0.5 h. Then the mixture is cooled to 10° and 4.9 g (30.4 mmol) of sodium bromoacetate is added followed by 40 ml dry dimethylformamide, and the reaction mixture is stirred at room temperature for 18 h. The reaction mixture is diluted with ether and water. The ether layer is separated and the aqueous phase is adjusted to pH=6.5 using 1N aqueous hydrochloric acid. The resulting solution is extracted thrice with ethyl acetate. The aqueous phase is again adjusted to pH=6.5 and extracted again. The combined organic phase is washed with brine, dried, filtered, and concentrated to give 8-hydroxy-4-[3-(3-pyridyl)propyl]-3-oxa-octanoic acid.
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