1,721,102 research outputs found
Labdane diterpenes from Marrubium velutinum and Marrubium cylleneum
No full textFrom the aerial parts of Marrubium velutinum and Marrubium cylleneum, seven labdane diterpenes, velutine A, 15-epi-velutine A, velutine B, 15-epi-velutine B, velutine C, cyllenine A and 15-epi-cyllenine A, have been isolated together with five known diterpenes and four known flavones. The structures of the isolated compounds were established by means of NMR [1H- 1H-COSY, 1H-13C-HMQC, HMBC, HMQC-TOCSY, NOESY] and MS spectral analyses. Complete NMR assignments are reported for known compounds. © 2005 Elsevier Ltd. All rights reserved
Secondary metabolites from Marrubium velutinum, growing wild in Greece
No full textFrom the aerial parts of Marrubium velutinum, two new phenylethanoid glycosides, velutinosides III-IV have been isolated together with four known phenylethanoid glycosides, as well as one new acylated flavone and five known flavonoids. The structures of the isolated compounds were established by means of NMR, MS, and UV spectral analyses. © 2005 Verlag der Zeitschrift für Naturforschung
Secondary metabolites from Stachys ionica
No full textNine flavonoids, two iridoids, and one sesquiterpene were isolated from Stachys ionica. Its chemical profile appears to be completely different from other species of Stachys growing in Greece. This differentiation is correlated to the distribution of S. ionica, confined to the Ionian Islands, and therefore, well-isolated from the rest of the species. © 2003 Elsevier Ltd. All rights reserved
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Acylated flavonoid and phenylethanoid glycosides from Marrubium velutinum
No full textFrom the aerial parts of Marrubium velutinum, one acylated flavonoid glycoside, chrysoeriol 7-O-(3′′,6′′-di-O-E-p-coumaroyl)-β -D-glucopyranoside, and two tetrasaccharidic phenylethanoid glycosides, velutinosides I-II, have been isolated together with ten known flavonoids and seven known phenylethanoid glycosides. The structures of the isolated compounds were established by means of NMR, MS, and UV spectral analyses. © 2003 Elsevier Ltd. All rights reserved
Sesquiterpene lactones from Anthemis melanolepis
No full textFrom the aerial parts of A melanolepis, two new sesquiterpene lactones, melanolepin B (= 1α,4β,8α-trihydroxyeudesm-11(13)-en-12, 6α-olide; 1) and melanolepin C (=1α,10β-epoxy-8β- hydroxygermacra-4(15), 11(13)-dien-12,6α-olide; 2), were isolated, together with four known compounds, desacetyllaurenobiolide, dentatin A, taraxasterol, and (3S,5R)-loliolide. Compound 1 was found to have the rare cis-fused eudesmane skeleton. The structures of the isolated compounds were established by means of NMR (1H, 1H-COSY, 1H,13C-HSQC, HMBC, NOESY) and MS analyses. © 2007 Verlag Helvetica Chimica Acta AG
Iridoids from Scutellaria albida ssp. albida
No full textThree iridoid glycosides, 6′-O-E-p-coumaroylgardoside (1), 6′-O-p-E-coumaroyl-8-epi-loganic acid (2) and scutelloside (3) were isolated from the aerial parts of Scutellaria albida subsp. albida, in addition to an anomeric mixture in equilibrium of one iridoid aglycone (4, 4a), nine iridoid glycosides (5-13), four known phenylethanoid glycosides (14-17), and six known phenolic derivatives (18-23). © 2007 Elsevier Ltd. All rights reserved
Cytotoxicity and immunomodulating characteristics of labdane diterpenes from Marrubium cylleneum and Marrubium velutinum
No full textFrom the aerial parts of Marrubium cylleneum, one labdane nor-diterpene has been isolated together with two labdane diterpenes, hitherto not known as natural products. The structures of the isolated compounds were established by means of NMR [1H-1H-COSY, 1H-13C-HSQC, HMQC-TOCSY, HMBC, NOESY] and MS spectral analyses. Several diterpenoids from M. cylleneum and M. velutinum were tested for their cytotoxic effect against various cancer cell lines and their immunomodulating potential in human peripheral blood mononuclear cells in standard in vitro assays. Our results show a differential cytotoxicity of some compounds as well as their ability to improve selected lymphocyte functions. © 2007 Elsevier Ltd. All rights reserved
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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