Molecule 43-45, Oxidation followed by Reduction

Molecule 43 undergoes an oxidation reaction through the use of PCC
in CH2Cl2 to create molecule 44 which then undergoes a reduction with
H2, AcOH, and PtO2 to continue to molecule 45. These conversions correspond to
steps 15 and 16 in the synthesis of Maoecrystal V, which is believed to have
some possible anti-cancer causing properties.

Peng, F.; Danishefsky, S. J. J. Am. Chem. Soc. 2012, 134, 18860−18867.