Anti-plasmodial activity-guided fractionation of Phlomis brunneogaleata (Lamiaceae) led to the isolation of two new metabolites, the iridoid glycoside, brunneogaleatoside and a new pyrrolidinium derivative (2S,4R)-2-carboxy-4-(E)-p-coumaroy- and X-ray crystallography. Compounds 10 and 11 were determined to be the major anti-malarial principles of the crude extract (IC 50 values of 2.4 and 5.9 mg/mL, respectively). They also exhibited significant leishmanicidal activity (IC 50 = 1.1 and 4.1 mg/mL, respectively). The inhibitory potential of the pure metabolites against plasmodial enoyl-ACP reductase (FabI), which is the key regulator of type II fatty acid synthases (FAS-II) in P. falciparum, was also assessed. Compound 10 showed promising FabI inhibiting effect (IC 50 = 10 mg/mL) and appears to be the first anti-malarial natural product targeting FabI of P. falciparum.

The qualitative and quantitative determination of phenylethanoid glycosides in methanolic extracts of five species of the genus Phlomis (Lamiaceae) has been investigated using a new reversed-phase HPLC method combined with photodiode-array detection and electrospray/MS analysis. Forsythoside B, verbascoside, samioside, alyssonoside, isoverbascoside, leucosceptosides A and B and martynoside were detected. The quantification of the above constituents was performed using echinacoside as internal standard. Knowledge of the content of phenylethanoid glycosides contributes to the chemotaxonomy of the genus.

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Volatile constituents of various solvent extracts (n-hexane, CH 2 Cl 2 , H 2 O) of 15 different organs (leaves, flowers, fruits) of five Rhododendron species (Ericaceae) growing in Turkey were trapped with headspace solid-phase microextraction (HS-SPME) technique and analyzed by GC-MS. A total of 200 compounds were detected and identified from organic extracts, while the water extracts contained only traces of few volatiles. The CH 2 Cl 2 extract of the R. luteum flowers was found to exhibit the most diverse composition: 34 compounds were identified, with benzyl alcohol (16.6%), limonene (14.6%) and p-cymene (8.4%) being the major compounds. The CH 2 Cl 2 -solubles of R. x sochadzeae leaves contained only phenyl ethyl alcohol. This study indicated appreciable intra-specific variations in volatile compositions within the genus. Different anatomical parts also showed altered volatile profiles. This is the first application of HS-SPME-GC-MS on the volatiles of Rhododendron species.