Abstract
A streamlined entry into the sesquiterpene lactone (SQL) cores of linearifolin and zaluzanin A is described. Stereochemistry is controlled through transformations uncovered by ISES (In Situ Enzymatic Screening). Absolute stereochemistry derives from kinetic resolution of 5-benzyloxypentene-1,2-oxide, utilizing a β-pinene-derived-Co(III)-salen. Relative stereochemistry (1,3-cis-fusion) is set via formal halometalation/carbocyclization, mediated by [Rh(O 2CC 3F 7) 2] 2/LiBr. Subsequent ring-closing metathesis (RCM-Grubbs II) yields the title exomethylene-δ-lactone SQL cores. In complementary fashion, RCM with Grubbs-I catalyst provides the oxabicyclo[3.3.1]nonyl core of xerophilusin R and zinagrandinolide.
Original language | English (US) |
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Pages (from-to) | 968-971 |
Number of pages | 4 |
Journal | Organic Letters |
Volume | 14 |
Issue number | 4 |
DOIs | |
State | Published - Feb 17 2012 |
ASJC Scopus subject areas
- Biochemistry
- Physical and Theoretical Chemistry
- Organic Chemistry