Pinky! To the lab!
We have some work to do!
Cephalostatin Western Half
22-epi-cephalostatin western half 30 (14.3 mg, 0.0210 mmol) and CSA (20 mg, 0.086 mmol) in dichloroethane was stirred under reflux for 22 hours, then cooled to room temperature. The reaction mixture was diluted with diethyl ether, washed 2 times with saturated aqueous NaHCO3, and washed 1 time with brine. Drying over Na2SO4 was followed by filtration and concentration under reduced pressure. Cephalostatin 1 western half (5) was obtained as a clear oil. (78% yield):FTIR (film, cm-1) 2966, 2930, 2858, 1711, 1471, 1447,
1427, 1388, 1369, 1312, 1282, 1244, 1231, 1220, 1180, 1111, 1101, 1071, 1048, 1029, 998, 971, 953, 906, 855, 822, 791, 770, 725, 702, 647, 624, 609, 575, 544, 542, 501.
