en
Scientific article
English

Targeted Isolation of Indolopyridoquinazoline Alkaloids from Conchocarpus fontanesianus Based on Molecular Networks

Published inJournal of Natural Products, vol. 79, no. 9, p. 2270-2278
Publication date2016
Abstract

A dichloromethane-soluble fraction of the stem bark of Conchocarpus fontanesianus showed antifungal activity against Candida albicans in a bioautography assay. Off-line high-pressure liquid chromatography activity-based profiling of this extract enabled a precise localization of the compounds responsible for the antifungal activity that were isolated and identified as the known compounds flindersine (17) and 8-methoxyflindersine (18). As well as the identification of the bioactive principles, the ultra-high-pressure liquid chromatography-high-resolution mass spectrometry metabolite profiling of the dichloromethane stem bark fraction allowed the detection of more than 1000 components. Some of these could be assigned putatively to secondary metabolites previously isolated from the family Rutaceae. Generation of a molecular network based on MS(2) spectra indicated the presence of indolopyridoquinazoline alkaloids and related scaffolds. Efficient targeted isolation of these compounds was performed by geometric transfer of the analytical high-pressure liquid chromatography profiling conditions to preparative medium-pressure liquid chromatography. This yielded six new indolopyridoquinazoline alkaloids (5, 16, 19-22) that were assigned structurally. The medium-pressure liquid chromatography separations afforded additionally 16 other compounds. This work has demonstrated the usefulness of molecular networks to target the isolation of new natural products and the value of this approach for dereplication. A detailed analysis of the constituents of the stem bark of C. fontanesianus was conducted.

Keywords
  • Alkaloids/chemistry/isolation & purification/pharmacology
  • Antifungal Agents/chemistry/isolation & purification/pharmacology
  • Biological Products/chemistry/isolation & purification/pharmacology
  • Brazil
  • Candida albicans/drug effects
  • Chromatography, High Pressure Liquid
  • Nuclear Magnetic Resonance, Biomolecular
  • Plant Bark/chemistry
  • Rutaceae/chemistry
Citation (ISO format)
CABRAL-CABECA, Rodrigo et al. Targeted Isolation of Indolopyridoquinazoline Alkaloids from Conchocarpus fontanesianus Based on Molecular Networks. In: Journal of Natural Products, 2016, vol. 79, n° 9, p. 2270–2278. doi: 10.1021/acs.jnatprod.6b00379
Main files (1)
Article (Published version)
accessLevelRestricted
Identifiers
ISSN of the journal0163-3864
209views
0downloads

Technical informations

Creation02/05/2020 3:08:00 PM
First validation02/05/2020 3:08:00 PM
Update time03/15/2023 9:11:01 PM
Status update03/15/2023 9:11:01 PM
Last indexation01/17/2024 9:04:38 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack