Noreupenifeldin, a tropolone from an unidentified ascomycete.
Noreupenifeldin ( 2), a new monotropolone derivative of the bistropolone eupenifeldin ( 1), was isolated from an unidentified ascomycete by bioassay-guided fractionation as part of our search for new anthelmintics. The structure of 1 was confirmed by comparison with literature data. The structure of 2 was elucidated from MS and 1D and 2D NMR data. Compounds 1 and 2 are diastereomers of pycnidione ( 3) and epolone A ( 4), respectively. Compounds 1- 3 were evaluated for their anthelmintic activity against the parasitic worm Hemonchus contortus. Compounds 1 and 3 exhibited modest in vitro activity, showing EC 90 50 and 83 microg/mL, respectively, in reducing motility of L3 larvae of H. contortus. Compound 2 was inactive, indicating that the second tropolone moiety is required for activity.
Ayers
Sloan
S
Merck Research Laboratories, Rahway, New Jersey 07065, USA.
Zink
Deborah L
DL
Powell
Joanne S
JS
Brown
Christine M
CM
Grund
Alan
A
Bills
Gerald F
GF
Platas
Gonzalo
G
Thompson
Donald
D
Singh
Sheo B
SB
D000818:Animals; D001203:Ascomycota / Q000737:chemistry*; D006189:Haemonchus / Q000187:drug effects; D015394:Molecular Structure; D014334:Tropolone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
C529039:noreupenifeldin; D014334:Tropolone