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Interesting Compounds (interesting + compound)
Selected Abstracts4,,,-Acetylvitexin-2,- O -rhamnoside, Isoorientin, Orientin, and 8-Methoxykaempferol-3- O -glucoside as Markers for the Differentiation of Crataegus monogyna and Crataegus pentagyna from Crataegus laevigata (Rosaceae)CHEMISTRY & BIODIVERSITY, Issue 12 2007Sonja Prinz Abstract In our chemotaxonomic investigation of pharmaceutically relevant Crataegus species, the qualitative and quantitative flavonoid fingerprint of Crataegus monogyna and C. pentagyna is presented. Six flavonoids were identified as vitexin-2,- O -rhamnoside (1), vitexin (2), isovitexin (3), rutin (4), hyperoside (5), and isoquercitrin (6). Besides the verification of the main compounds isoorientin (7) and orientin (8) in C. pentagyna, further four flavonoids were isolated and identified as isoorientin-2,- O -rhamnoside (9), orientin-2,- O -rhamnoside (10), isovitexin-2,- O -rhamnoside (11), and 8-methoxykaempferol-3- O -glucoside (12) by means of 1D- and 2D-NMR, MS, and UV analyses. Compound 12 was isolated for the first time from C. pentagyna. In contrast to C. pentagyna, C. monogyna samples were predominated by 4,,,-acetylvitexin-2,- O -rhamnoside (13), which was missing in C. pentagyna. Hence, 13 represents an interesting compound for chemotaxonomy of C. monogyna, whereas the main flavonoids 7, 8, and 12 could be proposed as markers for C. pentagyna. The absence of 7, 8, 12, and 13 in C. laevigata offers an appropriate tool for additional differentiation from C. monogyna and C. pentagyna, and for sample identification and quality control of the three main Crataegus species used in European phytotherapy. [source] Inhibition of NF-,B activation with designed ankyrin-repeat proteins targeting the ubiquitin-binding/oligomerization domain of NEMOPROTEIN SCIENCE, Issue 9 2007Emanuel Wyler Abstract The link between the NF-,B signal transduction pathway and cancer is now well established. Inhibiting this pathway is therefore a promising approach in the treatment of certain cancers through a pro-apoptotic effect in malignant cells. Owing to its central role in the pathway, the I,B kinase (IKK) complex is a privileged target for designing inhibitors. Previously, we showed that oligomerization of NEMO is necessary for IKK activation and defined a minimal oligomerization domain (CC2-LZ) for NEMO, and we developed NEMO peptides inhibiting NF-,B activation at the level of the IKK complex. To improve the low-affinity inhibitors, we used ribosome display to select small and stable proteins with high affinity against the individual CC2-LZ because the entire NEMO protein is poorly soluble. Several binders with affinities in the low nanomolar range were obtained. When expressed in human cells, some of the selected molecules, despite their partial degradation, inhibited TNF-,-mediated NF-,B activation while having no effect on the basal activity. Controls with a naive library member or null plasmid had no effect. Furthermore, we could show that this NF-,B inhibition occurs through a specific interaction between the binders and the endogenous NEMO, resulting in decreased IKK activation. These results indicate that in vitro selections with the NEMO subdomain alone as a target may be sufficient to lead to interesting compounds that are able to inhibit NF-,B activation. [source] Synthesis and Biological Evaluation of 2-Mercapto-1,3-benzothiazole Derivatives with Potential Antimicrobial ActivityARCHIV DER PHARMAZIE, Issue 10 2009Carlo Franchini Abstract The enhancement of bacterial resistance of pathogens to currently available antibiotics constitutes a serious public health threat. So, intensive efforts are underway worldwide to develop new antimicrobial agents. To identify compounds with a potent antimicrobial profile, we designed and synthesized low molecular weight 2-mercaptobenzothiazole derivatives 2a,2l and 3a,3l. Both series were screened for in-vitro antibacterial activity against the representative panel of Gram-positive and Gram-negative bacteria strains. The biological screening identified compounds 2e and 2l as the most active ones showing an interesting antibacterial activity with MIC values of 3.12 ,g/mL against Staphylococcus aureus and 25 ,g/mL against Escherichia coli, respectively. The replacement of the S-H by the S-Bn moiety resulted in considerable loss of the antibacterial action of the 3a,3l series. The antibiotic action of compounds 2e and 2l was also investigated by testing their activity against some clinical isolates with different antimicrobial resistance profile. Moreover, the involvement of the NorA efflux pump in the antibacterial activity of our molecules was evaluated. Finally, in this paper, we also describe the cytotoxic activity of the most interesting compounds by MTS assay against HeLa and MRC-5 cell lines. [source] Enantiomers of 2-[(Acylamino)ethyl]-1,4-benzodiazepines, Potent ligands of ,-opioid receptor: Chiral chromatographic resolution, configurational assignment, and biological activityCHIRALITY, Issue 9 2001O. Azzolina Abstract Compounds 2a and 3a,e are racemic 2-[(acylamino)ethyl]-1,4-benzodiazepines, tifluadom analogs, with high affinity and selectivity towards the ,-opioid receptor. We describe the enantiomeric separation of all compounds through liquid chromatography with chiral stationary phases, as well as the resolution of the enantiomers of the most interesting compounds, 2a and 3a, by the semipreparative column Chiralpak AD. The configuration of the resolved enantiomers was investigated: the comparative study of CD and 1H NMR spectra shows that compounds (,)- 2a and (,)- 3a have the same absolute configuration of (+)-(S)-tifluadom. A study on the stereoselective interaction with opiate receptors is reported. Chirality 13:606,612, 2001. © 2001 Wiley-Liss, Inc. 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