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Updated: Jul 18, 2026
10:49
Antibiotic Dereplication Using the Antibiotic Resistance Platform
Published on: October 17, 2019
[Structure of the pentaene antibiotic roseofungin]
Antibiotiki I Meditsinskaia Biotekhnologiia = Antibiotics and Medical Biotechnology
|May 1, 1986
Summary
This study identifies methyl branching in the roseofungin antibiotic's chromophore and pinpoints carbonyl group locations. Advanced spectroscopic methods determined the precise positions of key functional groups within this complex molecule.
Area of Science:
- Natural Product Chemistry
- Organic Chemistry
- Spectroscopy
Context:
- Roseofungin is a pentaene antibiotic belonging to the carbonyl-conjugated pentaene subgroup.
- Understanding the structural details of antibiotics like roseofungin is crucial for drug development and modification.
- Previous structural elucidation of roseofungin was incomplete, particularly regarding its oxygen-containing functions and chromophore branching.
Purpose:
- To determine the precise location of methyl branching within the roseofungin chromophore.
- To identify the positions of oxygen-containing functional groups, specifically carbonyls, in the roseofungin molecule.
- To elucidate the presence and formation of a hemiketal ring within the roseofungin structure.
Summary:
- Oxidation of roseofungin's perhydroderivative yielded 2-methyltridecan dicarboxylic acid, confirming methyl branching in the chromophore.
- Mass spectrometry analysis of reduced and isonolyzed roseofungin derivatives helped locate oxygen-containing functions.
- Deuterated reducing agents (lithium aluminum boron deuteride and sodium boron deuteride) identified carbonyl groups at C11 and C17.
- Carbon-13 Nuclear Magnetic Resonance (13C NMR) spectroscopy revealed a hemiketal ring formed between carbonyls C17 and C21.
Impact:
- Provides a detailed structural map of the roseofungin antibiotic, aiding in understanding its mechanism of action.
- The confirmed structural features, including methyl branching and carbonyl positions, can guide synthetic modifications for improved antibiotic properties.
- This research contributes to the broader field of natural product chemistry and the development of new antimicrobial agents.
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