University of Illinois Urbana-Champaign

Total synthesis of N-(benzyloxycarbonyl)didemnin A

Li, Kai-Ming

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Description

Title
Total synthesis of N-(benzyloxycarbonyl)didemnin A
Author(s)
Li, Kai-Ming
Issue Date
1990
Doctoral Committee Chair(s)
Rinehart, Kenneth L., Jr.
Department of Study
Chemistry
Discipline
Chemistry
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Chemistry, Organic
Language
eng
Abstract
Didemnin A, a cyclic depsipeptide isolated from a Caribbean tunicate, was synthesized by coupling two key fragments, (Boc-(3S,4R,5S)-Ist(TBDMS)-(2R,S;4S)-Hip-Leu-Pro-OH (Fragment I)) and (Z- scD-MeLeu-Thr(H-Me$\sb2$Tyr)-OTMSe) (Fragment II). Fragment I was synthesized, in turn, from Boc-(3S,4R,5S)-Ist(TBDMS)-OH, Bn-(2R,S;4S)-Hip-OH, Boc- scL-Leu-OH and H- scL-Pro-OMe by stepwise elongation of the peptide chain, starting from H-Pro-OMe. Fragment II was synthesized from Z- scD-MeLeu-OH, H- scL-Thr-OMe and Boc- scL-Me$\sb2$Tyr-OH, starting from Z- scD-MeLeu-OH. The heptapeptide Z- scD-MeLeu-Thr(Boc-(3S,4R,5S)-Ist-(2R,S;4S)-Hip-Leu-Pro-Me$\sb2$Tyr) -OTMSe was synthesized by coupling the two fragments between proline and dimethyltyrosine using Bop-Cl. After deprotection of TMSe and Boc groups, the cyclization was accomplished between threonine and isostatine, again using Bop-Cl. The $\sp1$H NMR and mass spectra and rotation of the synthesized N-Z-didemnin A are the same as those of natural N-Z-didemnin A.
Type of Resource
text
Permalink
http://hdl.handle.net/2142/20690
Copyright and License Information
Copyright 1990 Li, Kai-Ming

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