Enantiomeric synthesis of natural alkylglycerols and their antibacterial and antibiofilm activities

Abstract

Alkylglycerols (AKGs) are bioactive natural compounds that vary by alkyl chain length and degree of unsaturation, and their absolute configuration is 2S. Three AKGs (5l–5n) were synthesised in enantiomerically pure form, and were characterised for the first time together with 12 other known and naturally occurring AKGs (5a–5k, 5o). Their structures were established using ¹H and ¹³C APT NMR with 2D-NMR, ESI-MS or HRESI-MS and optical rotation data, and they were tested for their antibacterial and antibiofilm activities. AKGs 5a–5m and 5o showed activity against five clinical isolates and P. aeruginosa ATCC 15442, with MIC values in the range of 15–125 µg/mL. In addition, at half of the MIC, most of the AKGs reduced S. aureus biofilm formation in the range of 23%–99% and P. aeruginosa ATCC 15442 biofilm formation in the range of 14%–64%. The antibiofilm activity of the AKGs assessed in this work had not previously been studied.

Graphical Abstract

Keywords:

• Natural alkylglycerols
• 1-O-alkyl-sn-glycerols
• synthesis
• antibacterial
• antibiofilm

Acknowledgements

The authors are grateful to the Laboratory of Advanced Analytical Techniques in Natural Products, at the Universidad de los Andes, for ESI-MS and HRESI-MS analysis.

Supplementary material

Experimental details relating to this paper are available online alongside Figures S1–S37.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Dirección de Investigación, Universidad Nacional de Colombia [projects 20406 and 37110].