Tail Addition
The tail addition step in this synthesis (Scheme 6) was identical to that in the Nicolaou tail addition and was based on Oijma chemistry. The A ring was functionalized with a hydroxyl group through pyridinium chlorochromate oxidation of α-acylketone 49 to form ketone 50. Subsequent reduction using sodium borohydride produced alcohol 51 . Reaction of this alcohol with the Ojima lactam 52 and a concluding silyl deprotection step at two triethyl silyl positions in compound 53 gave Taxol.
| Scheme 6 |
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Read more about this topic: Danishefsky Taxol Total Synthesis
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