Madurastatins with Imidazolidinone Rings: Natural Products or Side-Reaction Products from Extraction Solvents?
Madurastatins are a group of pentapeptides containing an oxazoline moiety, and, in a few cases, an imidazolidinone ring as an additional structural feature. In our search for new potential antiparasitic metabolites from natural sources, we studied the acetone extracts from a culture of <i>Acti...
| Main Authors: | , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-12-01
|
| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/25/1/301 |
| Summary: | Madurastatins are a group of pentapeptides containing an oxazoline moiety, and, in a few cases, an imidazolidinone ring as an additional structural feature. In our search for new potential antiparasitic metabolites from natural sources, we studied the acetone extracts from a culture of <i>Actinomadura</i> sp. CA-135719. The LC/HRMS analysis of this extract identified the presence of the known madurastatins C1 (<b>1</b>), D1 (<b>4</b>), and D2 (<b>5</b>) together with additional members of the family that were identified as the new madurastatins H2 (<b>2</b>) and 33-<i>epi</i>-D1 (<b>3</b>) after isolation and spectroscopic analysis. The planar structures of the new compounds were established by HRMS, ESI-qTOF-MS/MS, and 1D and 2D NMR data, and their absolute configuration was proposed using Marfey’s and bioinformatic analyses of the biosynthetic gene cluster (BGC). A revision of the absolute configuration of madurastatins D1 and D2 is proposed. Additionally, madurastatins containing imidazolidinone rings are proved to be artifacts originating during acetone extraction of the bacterial cultures. |
|---|---|
| ISSN: | 1661-6596 1422-0067 |