Compound 1

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Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.

A mixture of S9 (20 mg, 0.19 mmol), THF (2 mL), EtOH (2 mL), water (2 mL) and lithium hydroxide (20 mg, 0.83 mmol) was heated at reflux for 1 h. After cooling to room temperature, ethyl acetate (5 mL) and water (5 mL) were added to the mixture. The mixture was acidified by addition of HCl(aq.) (1M) till pH = 2. The organic layer was separated and the water layer was extracted with ethyl acetate (5 mL). The combine organic layers were washed with brine and dried over Na₂SO₄. The solvent was evaporated and the residue was purified by column chromatography (SiO₂, dichloromethane:methanol = 20:1, R_f = 0.2) to yield a colorless oil. The obtained oil was placed in ether (5 mL) to yield motor 1 as a white solid (16 mg, 85%). Chiral separation of the enantiomers were performed by preparative HPLC (Chiralpak IC, Heptane/IPA/TFA 95/5/0.2, flow rate 0.7 mL/min). (R)-enantiomer was collected as the fraction with retention time of 18.5 min and the (S)-enantiomer was collected as the fraction with retention time of 21.3 min. ¹H NMR (500 MHz, Methylene Chloride-d₂) δ 7.50 (t, J = 9.9 Hz, 2H), 7.35 (t, J = 7.9 Hz, 1H), 7.23 (d, J = 7.7 Hz, 1H), 7.09 (t, J = 7.6 Hz, 1H), 7.01 (s, 1H), 6.90 (dd, J = 21.1, 7.9 Hz, 2H), 6.46 – 6.30 (m, 2H), 6.11 (d, J = 7.7 Hz, 1H), 4.30 – 4.06 (m, 5H), 4.01 (q, J = 7.1, 4.9 Hz, 1H), 3.93 (dd, J = 9.2, 6.6 Hz, 1H), 3.79 (dd, J = 11.2, 6.8 Hz, 1H), 3.19 – 3.02 (m, 1H), 2.40 (t, J = 7.2 Hz, 4H), 1.96 (t, J = 7.3 Hz, 4H), 1.85 (t, J = 7.2 Hz, 4H), 1.63 (tq, J = 29.7, 7.0 Hz, 12H), 1.53 – 1.26 (m, 40H), 0.93 (t, J = 6.8 Hz, 3H), 0.76 (d, J = 6.7 Hz, 3H). ¹³C NMR (125 MHz, Methylene Chloride-d₂) δ 182.0, 157.5, 156.6, 154.8, 141.0, 138.3, 137.7, 133.9, 133.6, 133.6, 130.0, 128.3, 128.0, 127.9, 127.3, 126.8, 126.3, 126.3, 125.8, 124.7, 123.3, 121.4, 111.4, 111.3, 111.0, 106.9, 106.8, 71.0, 71.0, 70.6, 38.5, 38.4, 35.9, 33.9, 32.4, 31.6, 31.6, 31.6, 31.5, 31.5, 31.4, 31.3, 31.3, 31.2, 31.2, 31.1, 31.1, 31.0, 28.1, 28.0, 27.9, 26.6, 24.6, 19.9, 19.8, 15.8. HRMS (ESI): calcd. for C₆₁H₈₅O₇S₂ [M+H] 993.5731, found 993.5734 and 1015.5548 [M+Na].