2026-09-21T07:32:58Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/20690 2023-07-10 col_2142_5131 col_2142_14789 com_2142_5130 com_2142_14788 com_2142_8903

Rinehart, Kenneth L., Jr. Li, Kai-Ming 2011-05-07T12:46:28Z 2011-05-07T12:46:28Z 10000-01-01 1990 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. Made available in DSpace on 2011-05-07T12:46:28Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9114316.pdf: 3574634 bytes, checksum: 08bc817016fa99c642f472b5a2732e87 (MD5) Previous issue date: 1990 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:45:36Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:20:13-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9114316 (UMI)AAI9114316 http://hdl.handle.net/2142/20690 eng Copyright 1990 Li, Kai-Ming Chemistry, Organic Total synthesis of N-(benzyloxycarbonyl)didemnin A text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.