Abstract
A series of substituted di-indolglyoxylamido-spermine analogues were prepared and evaluated for intrinsic antimicrobial properties and the ability to enhance antibiotic action. As a compound class, intrinsic activity was typically observed towards Gram-positive bacteria and the fungus Cryptococcus neoformans, with notable exceptions being the 5-bromo- and 6-chloro-indole analogues which also exhibited modest activity (MIC 34–50 μM) towards the Gram-negative bacteria Escherichia coli and Klebsiella pneumoniae. Several analogues enhanced the activity of doxycycline towards the Gram-negative bacteria Pseudomonas aeruginosa, E. coli, K. pneumoniae and Acinetobacter baumannii. Of particular note was the identification of five antibiotic enhancing analogues (5-Br, 7-F, 5-Me, 7-Me, 7-OMe) which also exhibited low to no cytotoxicity and red blood cell haemolytic properties. The mechanisms of action of the 5-Br and 7-F analogues were attributed to the ability to disrupt the integrity of, and depolarize, bacterial membranes.
Original language | English |
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Article number | 111708 |
Journal | European Journal of Medicinal Chemistry |
Volume | 183 |
DOIs | |
Publication status | Published - 1 Dec 2019 |
Externally published | Yes |
Scopus Subject Areas
- Pharmacology
- Drug Discovery
- Organic Chemistry
User-Defined Keywords
- Polyamine
- Indole
- Indolglyoxylamide
- Potentiation
- Antimicrobial