Article

Triterpene Glycosides from Antarctic Sea Cucumbers. 1. Structure of Liouvillosides A(1), A(2), A(3), B-1, and B-2 from the Sea Cucumber Staurocucumis liouvillei: New Procedure for Separation of Highly Polar Glycoside Fractions and Taxonomic Revision

Pacific Institute of Bioorganic Chemistry of the Far East Division of the Russian Academy of Sciences, Pr. 100-letya Vladivostoka 159, 690022, Vladivostok, Russian Federation.
Journal of Natural Products (Impact Factor: 3.95). 11/2008; 71(10):1677-85. DOI: 10.1021/np800173c
Source: PubMed

ABSTRACT Five new triterpene glycosides, liouvillosides A1 (1), A2 (2), A3 (3), B1 (4), and B2 (5), have been isolated from the Antarctic sea cucumber Staurocucumis liouviellei along with the known liouvilloside A(6), isolated earlier from the same species, and hemoiedemosides A (7) and B (8), isolated earlier from the Patagonian sea cucumber Hemioedema spectabilis. The isolation was carried out using a new chromatographic procedure including application of ion-pair reversed-phase chromatography followed by chiral chromatography on a cyclodextrin ChiraDex column. The structures of the new glycosides were elucidated using extensive NMR spectroscopy (1H and 13C NMR spectrometry, DEPT, 1H-(1)H COSY, HMBC, HMQC, and NOESY), ESI-FTMS, and CID MS/MS, and chemical transformations. Glycosides 1-3 are disulfated tetraosides and glycosides 4 and 5 are trisulfated tetraosides. Glycosides 2 and 3 contain 3-O-methylquinovose, found for the first time as a natural monosaccharide in sea cucumber glycosides. On the basis of analyses of glycoside structures a taxonomic revision is proposed.

Download full-text

Full-text

Available from: Sergi Taboada, Jul 06, 2015
0 Followers
 · 
256 Views
  • Source
    Marine Ecosystems, 03/2012; , ISBN: 978-953-51-0176-5
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: El estudio de las interacciones entre los organismos mediadas por sustancias químicas, lo que se denomina ecología química, nos da información sobre la biología de las especies implicadas, el funcionamiento de la comunidad en que viven y nos puede proporcionar además el conocimiento de nuevas sustancias que pueden ser útiles para el ser humano. En el marco de nuestros estudios sobre la ecología química de los invertebrados antárticos, en el proyecto ECOQUIM (2003-2006) se recolectaron numerosas muestras biológicas a partir de las cuales se obtuvieron extractos y sustancias naturales de invertebrados antárticos. En el proyecto ACTIQUIM (2007-actualidad), se ha evaluado el papel ecológico de estos extractos y sustancias naturales mediante experimentos de ecología química in situ (repelencia, defensa ante distintos tipos de macro y micro-depredadores, toxicidad, citotoxicidad y actividad antifouling) y también se ha analizado la actividad antitumoral de algunos compuestos obtenidos recientemente. Nuestros resultados demuestran, entre otras cuestiones, que las defensas químicas en los organismos antárticos son elevadas en las esponjas, los cnidarios, los tunicados, los briozoos, los equinodermos y los moluscos y que por lo tanto, estos grupos pueden ser una fuente rica en metabolitos secundarios con bioactividad, tanto a nivel ecológico como farmacológico. The study of the relationships between organisms mediated by chemicals (chemical ecology) can provide valuable information about the biology of the species, their role within the community and our knowledge of new molecules potentially useful to human beings. Within our ECOQUIM Project (2003-2006), we collected many biological samples that allowed us to obtain extracts and bioactive natural products from Antarctic benthic invertebrates. During the ACTIQUIM Project (2007 and on) the ecological activities of the marine natural products obtained have been determined by in situ chemical ecology experiments (repellence, defence, toxicity, cytotoxicity and antifouling). Also, the pharmacological potential has been analyzed by testing the antitumoral activity of selected compounds recently described. Our results show that chemical defences are abundant in Antarctic sponges, cnidarians, echinoderms, bryozoans, tunicates and mollusks, and that these zoological groups can be considered as a rich source of bioactive secondary metabolites of importance both in ecology and in pharmacology.
  • [Show abstract] [Hide abstract]
    ABSTRACT: KLa(WO4)2 crystal congruently melts at 1136 °C. Yb3+:KLa(WO4)2 crystal with the dimension of Φ27×55 mm3 has been grown by the Czochralski method. The absorption and fluorescence spectra of Yb3+:KLa(WO4)2 crystal were investigated.
    Journal of Crystal Growth 02/2005; 274(s 3–4):469–473. DOI:10.1016/j.jcrysgro.2004.10.033 · 1.69 Impact Factor