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Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Total synthesis and structural elucidation of khafrefungin
T Wakabayashi1, K Mori, S Kobayashi
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|July 18, 2001
Summary
Researchers achieved total synthesis of the novel antifungal agent khafrefungin. This compound selectively targets fungal sphingolipid synthesis without affecting mammals, offering a promising therapeutic avenue.
Area of Science:
- Medicinal Chemistry
- Organic Synthesis
- Mycology
Background:
- Khafrefungin is a novel antifungal agent discovered from fermentation culture MF6020.
- Existing antifungal agents often inhibit enzymes in both fungi and mammals, leading to side effects.
- Selective inhibition of fungal targets is crucial for developing safer antifungal therapies.
Purpose of the Study:
- To achieve the total synthesis of khafrefungin.
- To elucidate the complete stereochemistry of khafrefungin.
- To investigate the selective mechanism of khafrefungin as an antifungal agent.
Main Methods:
- Stereoselective synthesis of simplified khafrefungin mimics (1 and 2) to determine relative stereochemistry.
- Comparative spectral analysis of synthetic mimics and natural khafrefungin.
- Tin(II)-catalyzed asymmetric aldol reactions for key synthetic steps.
Main Results:
- Complete stereochemical assignment of khafrefungin was achieved through synthesis and analysis of eight possible stereoisomers.
- Total synthesis of khafrefungin was successfully accomplished.
- Khafrefungin demonstrated selective inhibition of fungal sphingolipid synthesis, sparing mammalian pathways.
Conclusions:
- The total synthesis and structural elucidation of khafrefungin have been successfully completed.
- Khafrefungin represents a novel class of antifungal agents with selective action.
- Its unique mechanism offers potential for developing safer and more effective antifungal treatments.
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