Dimethylformamide → 197915-37-0

Participants

Reaction Steps

The title compound was prepared as described in General Method 9 using 0.23 g (0.65 mmol) of N-{4-[2-(4-hydroxy-6-oxo-2-phenyl-3,6-dihydro-2H-pyran-2-yl)-ethyl]-phenyl}-acetamide (prepared in Example RR), 0.33 g (0.90 mmol) of toluene-4-thiosulfonic acid S-(2-tert-butyl-4-hydroxymethyl-5-methyl-phenyl) ester (prepared in Example FFF), 0.54 g (3.9 mmol) of K2CO3, and 5 mL of DMF. The solution was stirred overnight at room temperature and then poured into glacial acetic acid (5 mL) and EtOAc (20 mL). After standard work-up, the residue was triturated with Et2O, and the solids were filtered. The penultimate intermediate was dissolved in H2O (30 mL), 50% NaOH (4 mL), and MeOH (5 mL) and was refluxed for 18 hours. The mixture was cooled to room temperature, concentrated, and suspended in phosphate buffer (pH 7.5). Acidification to pH 6.8 with phosphoric acid was followed by extraction with CH2Cl2. The combined extracts were washed with brine, dried (MgSO4), and concentrated to give the title compound, m.p. 218°-221° C. 1H NMR (DMSO-d6) δ 1.44 (s, 9 H), 1.76 (s, 3 H), 2.05-2.22 (m, 3 H), 2.40 (m, 1 H), 3.40 (m, partially obscured by H2O, 2 H), 4.32 (s, 2 H), 4.90 (br s, 1 H), 6.17 (s, 1 H), 6.47 (d, 2 H), 6.75 (d, 2 H), 7.21 (s, 1 H), 7.38-7.43 (m, 5 H).

Provenance & Evidence