Stereoselective total synthesis of (+)-giganin and its C10 epimer by using late-stage lithiation-borylation methodology.
The first total synthesis of (+)-giganin and its unnatural diastereoisomer (+)-C10-epi-giganin has been completed in a total of 13 linear steps, and 7 % and 8 % overall yield, respectively (see scheme; (-)-sp= (-)-sparteine, (+)-sps=(+)-sparteine surrogate). Lithiation-borylation methodology has been successfully applied in the key step, to couple together advanced intermediates with very high diastereoselectivity, thus demonstrating its power as a tool for total synthesis.
School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
Catherine J
CJ
Fletcher
Katherine M P
KM
Wheelhouse
Varinder K
VK
Aggarwal
D054378:Acetogenins / Q000138:chemical synthesis* / Q000737:chemistry; D001896:Boron Compounds / Q000737:chemistry*; D060326:Chemistry Techniques, Synthetic / Q000379:methods; D018020:Lithium Compounds / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
D054378:Acetogenins; D001896:Boron Compounds; D018020:Lithium Compounds