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Extracts from Epilobium sp. herbs have been traditionally used in the treatment of prostate-associated ailments. Our studies demonstrated that the extracts from Epilobium angustifolium, Epilobium parviflorum and Epilobium hirsutum herbs are potent prostate cancer cells (LNCaP) proliferation inhibitors with IC50 values around 35 mg/ml. The tested extracts reduced prostate specific antigen (PSA) secretion (from 325.625.3 ng/ml to ~90 ng/ml) and inhibited arginase activity (from 65.21.1 mUnits of urea/mg of protein to ~40 mUnits of urea/mg protein). Selected constituents of extracts (oenothein B, quercetin-3-O-glucuronide, myricetin-3-O-rhamnoside) were proventobeactiveinrelationtoLNCaPcells.However,oenotheinBwasthestrongestinhibitorofcellsproliferation (IC50=7.80.8 mM), PSA secretion (IC50=21.93.2 mM) and arginase activity (IC50=19.22.0 mM). Additionally, ellagitannins from E. hirustum extract were proven to be transformed by human gut microbiota into urolithins. Urolithin C showed the strongest activity in the inhibition of cell proliferation (IC50=35.23.7 mM), PSA secretion (reduced PSA secretion to the level of 100.731.0 ng/ml) and arginase activity (reduced to the level of 27.93.3 mUnits of urea/mg of protein). Results of the work offer an explanation of the activity of Epilobium extractsand supporttheuseof Epilobium preparationsin thetreatment of prostate diseases. Copyright © 2013 John Wiley & Sons, Ltd.

Four new hydroxy-aminoalkyl derivatives of α,β-unsaturated macrolide-josamycin (2–5) have been synthesised and their structures have been studied by means of 1H and 13C NMR and FT-IR methods. Complete assignment of resonances in the 1H and 13C NMR spectra has been made on the basis of 1H13C HSQC, 1H13C HMBC, 1H1H COSY, 1H1H NOESY 2D experiments. Spectroscopic data indicated that for the derivatives 3 and 4 some equilibrium between two different structures exists in contrast to derivatives 2 and 5. The lowest-energy structures of the new derivatives of josamycin have been calculated and visualised by PM5 method at semi-empirical level of theory, taking into account the NMR and FT-IR data. The most significant differences between the structures of josamycin and its newly synthesised derivatives' were found in the conformation of the macrolide aglycone part and in the mutual orientation of the 4-O-isovalerylmycarosylmycaminose moiety relative to the aglycone part. PM5 semi-empirical calculations indicated that the structures of the new macrolide derivatives are stabilised by rather weak intramolecular hydrogen bonds in agreement with spectroscopic data. Antimicrobial properties of the new derivatives 2–5 as well as those having an acetate group at C-3 (6 and 7) were determined and compared to that of the parent macrolide antibiotic josamycin (1). Copyright © 2010 John Wiley & Sons, Ltd.

Anhydrides, imides, N-ethylimides, N-hydroxyimides and N-aminoimides of 1,4,5,6-tetramethyl-bicyclo[5.2.1.0 2,6 ]hept-5-ene-2,3-dicarboxylic acid, 1,4,5,6,7-pentamethyl-bicyclo[5.2.1.0 2,6 ]hept-5-ene-2,3-dicarboxylic acid and 7-ethyl-1,4,5,6-tetramethyl-bicyclo[5.2.1.0 2,6 ]hept-5-ene-2,3-dicarboxylic acid were obtained. Antimicrobial activity of the newly obtained derivatives was tested against selected Gram-positive and Gram-negative bacteria and fungi of the Candida species. The structures of obtained compounds and their antimicrobial activity were compared. Structure of 1b, 2b and 1e were determined by an X-ray analysis.

X-ray data of crystals of monensin A phenylurethane sodium salt (I) shows that the compound forms a pseudocyclic structure, stabilized by three intramolecular hydrogen bonds and the sodium cation coordinated by five oxygen atoms in the hydrophilic sphere.

The synthesized compounds are screened for their antibacterial activity, but only three of the tested substances show weak potency against Gram-positive bacteria.