Hybrids of β-triketone and monoterpenoids from the peels of Callistemon viminalis

Fitoterapia. 2023 Apr:166:105459. doi: 10.1016/j.fitote.2023.105459. Epub 2023 Feb 16.

Abstract

Phytoconstituents of the peels of Callistemon viminalis has been investigated for the first time. As a result, two pair of diastereomers of hybrids of β-triketone and α-phellandrene, named viminalisones A-B (1-2) and viminalisones CD (3-4), and three known analogues were obtained. Their structures and absolute configurations were elucidated through a combination of the analysis of their MS data, NMR spectra, single-crystal X-ray diffraction, and their experimental and calculated electronic circular dichroism (ECD) spectra. All isolates were evaluated for their antimicrobial activities against Botrytis cinerea and Cutibacterium acnes. Meroterpenoid 7 exhibited antibacterial activity against Botrytis cinerea with a MIC value of 0.256 mg/mL.

Keywords: Antibacterial activity; Callistemon viminalis; Meroterpenoids; Viminalisones A-D.

MeSH terms

  • Botrytis
  • Microbial Sensitivity Tests
  • Molecular Structure
  • Monoterpenes*
  • Myrtaceae* / chemistry

Substances

  • Monoterpenes

Supplementary concepts

  • Botrytis cinerea