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Published on: September 30, 2014
Pneumocandins from Zalerion arboricola. III. Structure elucidation
O D Hensens1, J M Liesch, D L Zink
1Department of Natural Products Chemistry, Merck Research Laboratories, Rahway, N.J. 07065-0900.
The Journal of Antibiotics
|December 1, 1992
Summary
Pneumocandin B0 and related lipopeptides, identified as antifungal and anti-Pneumocystis agents, were isolated from Zalerion arboricola mutants. Spectroscopic analysis confirmed their structures, classifying them within the echinocandin class of antifungals.
Area of Science:
- Microbiology
- Medicinal Chemistry
- Natural Products
Background:
- Zalerion arboricola mutants produce lipopeptides with antifungal properties.
- Pneumocandin B0 and related compounds exhibit activity against fungi and Pneumocystis carinii.
- These compounds belong to the echinocandin class, known for antifungal activity.
Purpose of the Study:
- To isolate and characterize novel antifungal lipopeptides from Zalerion arboricola.
- To elucidate the structures of Pneumocandin B0 and related compounds.
- To investigate modifications of pneumocandin A0.
Main Methods:
- Isolation of lipopeptides from Zalerion arboricola mutants.
- Structure determination using spectroscopic analysis (e.g., NMR, Mass Spectrometry).
- Chemical modification and characterization of specific residues.
Main Results:
- Pneumocandin B0 and six related lipopeptides were isolated and structurally characterized.
- The structure of a base-catalyzed ring-opened product (6b) of Pneumocandin B0 was defined.
- Modifications were identified in specific amino acid residues (3-hydroxy-4-methylproline, 3,4-dihydroxyhomotyrosine, 4,5-dihydroxyornithine).
Conclusions:
- Novel echinocandin-class antifungal agents were discovered from Zalerion arboricola.
- Detailed structural information was obtained for Pneumocandin B0 and its derivatives.
- The study provides insights into the chemical diversity and modification potential of pneumocandins.
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