Four monocyclic precursors were assembled in the total synthesis of the proposed structure 1-A of (+)-tolyporphin A O,O-diacetate (X=Ac). Comparison of the spectroscopic data demonstrated that synthetic tolyporphin O,O-diacetate did not match the O,O-diacetate prepared from natural (+)-tolyporphin A (X=H), calling for a structural revision of this class of natural products. On the basis of a series of NMR experiments including synthetic intermediates, the structure of tolyporphin A is concluded to be 1-B, in which the configurations of quaternary centers C7 and C17 are opposite to those in the originally proposed structure.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/(SICI)1521-3773(19990401)38:7<926::AID-ANIE926>3.0.CO;2-W | DOI Listing |
Publication Analysis
Top Keywords
structure tolyporphin
8
proposed structure
8
revised structure
4
tolyporphin monocyclic
4
monocyclic precursors
4
precursors assembled
4
assembled total
4
total synthesis
4
synthesis proposed
4
structure 1-a
4
Similar Publications
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!