A nanotemplate surface that functions as a regular array of traps for molecules such as naphthalocyanine (see picture) is provided by a nanomesh of hexagonal BN on Rh(111), which has now been identified as a single, complete monolayer. The 2‐nm‐sized pores form at regions where the layer binds strongly to the underlying metal, while the regular network of mesh wires corresponds to regions where the layer is not bonded to the substrate.

The effects of 15 jatrophane diterpene polyesters (1-3 and 5-16) isolated from lipophilic extracts of Euphorbia serrulata, E. esula, E. salicifolia, and E. peplus (Euphorbiaceae) on the reversion of multidrug resistance of mouse lymphoma cells were examined. The structures of five new compounds (1-5) were elucidated by spectroscopic methods, including HRFABMS, ESIMS, (1)H-(1)H homonuclear and (1)H-(13)C heteronuclear correlations, long-range correlation spectra, and NOESY experiments. The stereochemistry and absolute configuration of one compound (3) were determined by X-ray crystallography. The structure-activity relationship is discussed.

The antioxidant effects of aqueous methanolic extracts from three medicinal Lamiaceae species were investigated in enzyme-dependent and enzyme-independent lipid peroxidation systems. All these extracts caused a considerable concentration-dependent inhibition of lipid peroxidation. Phenolic components present in the plant extracts were evaluated for antioxidant activity and were found effective in both tests. Their concentrations in each extract were determined by TLC-densitometry.

The protective effects of eleven Salvia species native to Europe against enzyme-dependent and enzyme-independent lipid peroxidation were evaluated. The 50% aqueous methanolic extracts of the leaves of all tested plants were found to be more effective than the positive control alpha-tocopherol acid succinate. The extracts of S. candelabrum, S. ringens, S. tomentosa, S. nemorosa, and S. glutinosa displayed considerable concentration-dependent antioxidative effects that were comparable to those of the medicinal and aromatic plant S. officinalis. The concentrations of flavonoids, hydroxycinnamic acids and total phenolic compounds in each extract were quantified with the aim of clarifying the connection between activity and chemical composition.

The dried aerial parts of Euphorbia mongolica afforded three new acylated polyhydroxy diterpenoids based on the jatrophane framework. The structures were established by means of a combination of 1D and 2D NMR techniques and mass spectrometry as (2S,3S,4R,5R,7S,8R,13S,15R)-5alpha,7beta,8alpha-triacetoxy-3beta-benzoyloxy-15beta-hydroxyjatropha-6(17),11E-diene-9,14-dione (1), (2S,3S,4R,5R,7S,8S,9S13S,15R)-5alpha,7beta,8alpha,9alpha,15beta-pentaacetoxy-3beta-benzoyloxyjatropha-6(17),11E-dien-14-one (2), and (2S,3S,4R,5R,7S,8S,9S13S,15R)-3beta,7beta,8alpha,9alpha,15beta-pentaacetoxy-5alpha-benzoyloxyjatropha-6(17),11E-dien-14-one (3). When the isolates were assayed for multidrug resistance-reversing activity in a rhodamine 123 exclusion test using L5178 mouse lymphoma cells, all compounds demonstrated a concentration-dependent effect in inhibiting the efflux pump activity of these tumor cells in the range 11.2-112 microM.

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Phytochemical study of the aerial parts of Euphorbia grandicornis led to the isolation of two new tigliane diterpenes, 16-angeloyloxy-13α-isobutanoyloxy-4β,9α,20-trihydroxytiglia-1,5-diene-3,7-dione (1) and 16-angeloyloxy-13α-isobutanoyloxy-4β,9α,7β-trihydroxytiglia-1,5-dien-3-one (2). The structures and relative configuration of the new compounds were elucidated on the basis of extensive spectroscopic analysis, including 1D and 2D NMR experiments ((1)H NMR, JMOD, (1)H-(1)H COSY, NOESY, HSQC, and HMBC), mass spectrometry, and comparison with literature data. The biogenesis of 1 and 2 with respect to the unusual 5-en-7-one and 5-en-7-ol moieties is also discussed.

Phytochemical study of whole, undried plants of Euphorbia esula led to the isolation of six new (1-6) jatrophane diterpene polyesters, named esulatins H-M, together with the known compounds 2α,3β,5α,7β,15β-pentaacetoxy-9α-nicotinoyloxyjatropha-6(17),11-dien-14-one (7), salicinolide (8), and euphosalicin (9). The structures and relative configuration of 1-6 were established on the basis of extensive spectroscopic analysis, including HRESIMS and one- and two-dimensional NMR techniques. All these compounds, together with diterpenes (10-14) isolated previously from this plant, were evaluated for their antiproliferative activity against HeLa, Ishikawa, and MCF7 cells. The multidrug-resistance-reversing activities were also investigated on L5178 mouse lymphoma cells transfected with the pHa MDR1/A retrovirus DNA. Preliminary structure-activity relationship data are discussed.