Reaction Steps
To a solution of ketone 17 (59.0 mg, 0.0788 mmol, 1.0 equiv) in MeOH (5.0 mL, 0.015M) in a 15 mL rb flask at 0° C. was added NaBH4 (6.0 mg, 0.158 mmol, 2.0 equiv) in one portion. After 30 min at 0° C., the reaction was quenched by addition of acetone (0.1 mL), and then concentrated under reduced pressure. Purification was accomplished by flash chromatography column on a 3×12 cm column, eluting with 40% EtOAc/hexanes, collecting 18×150 mm test tube fractions. The product containing fractions (6-10) were combined and concentrated under reduced pressure to give the alcohol product 4 (55.6 mg, 94% yield) as colorless oil: Rf=0.40 (50% EtOAc/Hexanes); [α]D20=+16 (c=0.29, CHCl3); 500 MHz 1H NMR (CDCl3) δ 7.70-7.66 (m, 4H), 7.46-7.37 (m, 6H), 7.17 (d, J=8.7 Hz, 2H), 6.84 (d, J=8.7 Hz, 2H), 4.45 (d, J=10.8 Hz, 1H), 4.38 (d, J=11.1 Hz, 1H), 4.40-4.32 (m, 1H), 4.15-4.02 (dddddd, J=18.1, 10.7, 10.7, 7.1, 7.1, 7.1 Hz, 2H), 3.91-3.86 (m, 1H), 3.82-3.74 (m, 7H), 3.56-3.50 (m, 1H), 3.46-3.39 (m, 1H), 2.50 (d, J=5.5 Hz, 1H), 2.49 (d, J=3.0 Hz, 1H), 1.97 (ddd, J=12.4, 4.4, 2.4 Hz, 1H), 1.90-1.76 (m, 4H), 1.68-1.45 (m, 5H), 1.20 (t, J=7.1 Hz, 3H), 1.06 (s, 9H), 0.12 (s, 9H); 125 MHz 13C NMR (CDCl3) δ 171.8, 159.3, 135.8, 135.8, 134.1, 134.1, 131.2, 129.8, 129.5, 127.9, 127.9, 114.0, 72.9, 72.1, 72.1, 71.7, 68.3, 66.8, 60.7, 60.5, 55.5, 43.9, 42.9, 42.3, 41.8, 41.5, 37.8, 27.1, 19.4, 14.4, 0.5; 125 MHz DEPT 13C NMR (CDCl3) CH3 δ 55.5, 27.1, 14.4, 0.5; CH2 δ 71.7, 60.7, 60.5, 43.9, 42.9, 42.3, 41.8, 41.5, 37.8; CH δ 135.8, 135.8, 129.8, 129.5, 127.9, 127.9, 114.0, 72.9, 72.1, 68.4, 66.8; C δ 171.8, 159.3, 134.1, 134.1, 131.2, 19.4; IR (neat) 3440, 2940, 1735, 1612, 1513, 1428, 1376, 1250, 1175, 1109, 1037, 741, 704, 613, 536 cm−1; HRMS (ESI/APCI) calcd for C42H62O8Na (M+Na) 773.3881. found 773.3886.
