Silvocarcin M is isolated from Streptomyces strains and has strong antitumor activity. OMe OH OMe H OH OH CH3 H3C OH Gilvocarcin M Suzuki and coworkers were able to carry out the total synthesis of naturally occurring (-)-gilvocarcin M. Their synthesis included the following steps. (The wavy line means that stereochemistry is unspecified or is a mixture.) The stereochemistry of the product appears to be counterintuitive (apparent attack from the more hindered side). The rea- son is that the reaction involves initial O-alkylation followed by a rearrangement that need not concern us. OBn OBn H OBn H OBn OBn CH Lewis acid HO OBn CH AcO we НО Bn = CH,Ph OBn OBn %3! (A) (В)

Silvocarcin M is isolated from Streptomyces strains and has strong antitumor activity. OMe OH OMe H OH OH CH3 H3C OH Gilvocarcin M Suzuki and coworkers were able to carry out the total synthesis of naturally occurring (-)-gilvocarcin M. Their synthesis included the following steps. (The wavy line means that stereochemistry is unspecified or is a mixture.) The stereochemistry of the product appears to be counterintuitive (apparent attack from the more hindered side). The rea- son is that the reaction involves initial O-alkylation followed by a rearrangement that need not concern us. OBn OBn H OBn H OBn OBn CH Lewis acid HO OBn CH AcO we НО Bn = CH,Ph OBn OBn %3! (A) (В)

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter24: Catalytic Carbon-carbon Bond Formation

Section: Chapter Questions

Problem 24.37P

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