[OH:1][C:2]1[CH:7]=[C:6]([OH:8])[CH:5]=[CH:4][C:3]=1[CH:9]1[CH2:14][CH2:13][CH2:12][C:11](=O)[CH2:10]1.Cl.[O:17]([NH2:19])C.[C:20]([O-])(=O)C.[Na+].O(N)C>C(O)C>[CH3:20][O:1][C:2]1[CH:7]=[C:6]([OH:8])[CH:5]=[CH:4][C:3]=1[CH:9]1[CH2:14][CH2:13][CH2:12][C:11](=[N:19][OH:17])[CH2:10]1(±)-3-(2,4-Dihydroxyphenyl)cyclohexanone (22 mg), methoxylamine hydrochloride (18 mg) and sodium acetate (18 mg) were heated under reflux in ethanol. After 6 hr, further methoxylamine (36 mg) and sodium acetate (36 mg) were added and the mixture heated under reflux for a further 1 hr. The reaction mixture was evaporated in vacuo and the residue was partitioned between ethyl acetate (20 ml) and water (20 ml). The aqueous layer was extracted with ethyl acetate (2×20 ml), and the combined organic extracts were dried over magnesium sulfate and evaporated in vacuo. The crude residue was purified by flash column chromatography (SiO2, ethyl acetate/petrol, 1:1 v/v) to furnish the title compound as a mixture of isomers (18 mg, 72%). δH (CDCl3) 1.5-2.2 (6H, overlapping m), 2.42 (0.5H, bd), 2.69 (0.5H, bd), 2.92 (0.5H, m), 3.06 (0.5H, m), 3.24-3.38 (1H, m), 3.81 (1.5H, s), 3.88 (1.5H, s), 5.42 (0.5H, bs), 5.47 (0.5H, bs), 6.28-6.42 (2H, overlapping m), 6.86 (0.5H, bs), 6.98 (1H, m), 7.06 (0.5H, bs); m/z (ES−) 469 (2M−1)−.
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