Prenylated or geranylated flavonoids have been studied for their promising antiproliferative and cytotoxic activities. Twelve natural geranylated flavonoids (1-12) were isolated from the fruit of Paulownia tomentosa Steud. Their structures were elucidated using UV and IR spectroscopy, mass spectrometry, and 1D and 2D NMR spectroscopy. The absolute configurations were determined using NMR and circular dichroism. Seven of the compounds were characterized as new geranylated derivatives isolated from a natural source for the first time, namely 3'-O-methyl-5'-hydroxyisodiplacone (3), paulodiplacone A (5), tomentone II (6), tomentone B (7), tomentodiplacone P (8), paulodiplacone B (9), and tomentoflavone A (12). After 24 h of incubation at concentrations in the range 1-30 μM, the isolated compounds were tested for their antiproliferative and cytotoxic potentials against the human monocytic leukaemia cell line THP-1, using WST-1 and LDH assays, respectively. Almost all of the test compounds induced a concentration-dependent reduction in the metabolic activity of THP-1 cells and a concentration-dependent reduction in the cell viability. Diplacone (1) was the most potent antiproliferative and cytotoxic agent (IC50 9.31 ± 0.72 μM, LC50 18.01 ± 1.19 µM). 3'-O-Methyl-5'-hydroxydiplacone (2) showed relatively strong antiproliferative effect (IC50 12.61 ± 0.90 μM) and weaker cytotoxic activity (LC50 > 30 μM), indicating that it may serve as a potential lead compound for further testing. The structure-activity relationship for the 12 isolated compounds is discussed.

Department of Food Quality and Safety Czech University of Life Sciences Prague Kamýcká 129 16500 Prague 6 Suchdol Czech Republic

Department of Natural Drugs Faculty of Pharmacy Masaryk University Palackého tř 1946 1 61200 Brno Czech Republic

Department of Pharmaceutical and Pharmacological Sciences University of Padua Via F Marzolo 5 35131 Padua Italy

Department of Pharmacology and Toxicology Faculty of Pharmacy Masaryk University Palackého tř 1946 1 61200 Brno Czech Republic

Citace poskytuje Crossref.org

Identification of Plant Phenolics from Paulownia tomentosa and Morus alba as Novel PPARγ Partial Agonists and Hypoglycemic Agents

New potent N-hydroxycinnamamide-based histone deacetylase inhibitors suppress proliferation and trigger apoptosis in THP-1 leukaemia cells

Prenylated Flavonoids in Topical Infections and Wound Healing