Fragment Union and Total Synthesis of Bryostatin

Step 1,84% Yield Step 2,90% Yield Step 3,97% Yield 

Both compounds are used in the next step R = TBDPS 

Target Bryostatin 7 Bryostatin 2 Bryostatin 3 Bryostatin 16 Bryostatin 1 Bryostatin 9 Bryostatin 7 

Only transformations in the longest linear sequence (LLS) are considered. The term skeleton constructions refers to C-C and C-O bond formations (notwithstanding redox reactions) that directly introduce native structural features of the bryostatins without further modification. The term other functional group manipulations refers to steps that indirectly introduce native structural elements, the interconversion of functional groups (e.g., the introduction and removal of auxiliaries) and miscellaneous transformations that do not involve skeleton construction 

Pettit GR, Herald CL, Doubek DL, Herald DL, Arnold E, Clardy J (1982) J Am Chem Soc 

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