Linked Life Data

20663528

Source:http://linkedlifedata.com/resource/pubmed/id/20663528

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14-15
pubmed:dateCreated
2010-9-9
pubmed:abstractText
Twelve pyramidatins, i.e., dibenzocyclooctadiene-type lignans, together with Machilin G, were isolated from the dichloromethane extracts of aerial material of Talauma gloriensis, Magnolia fraseri, and Magnolia pyramidata (Magnoliaceae). These lignans contain a highly oxidized 7,9'-epoxy-2,2'-cyclolignane skeleton. Their structures were established using NMR spectroscopy (1D and 2D experiments) and mass spectrometry. The absolute configurations of five pairs of atropisomers (S(a)/R(a)-pyramidatins) and two single atropisomers (S(a)-pyramidatins) were determined by experimental and calculated circular dichroism (CD). In addition, the absolute configuration of (S(a))-3,3',4,4',5,5'-hexamethoxypyramidatin was confirmed using X-ray crystallography. Five pyramidatins, (R(a))-3,3',4,4',5,5'-hexamethoxypyramidatin, (R(a))-3,3'-dimethoxy-4,5:4',5'-bis(methylenedioxy)pyramidatin, (S(a))-3,3',4,5'-tetramethoxy-4,5-methylenedioxypyramidatin, (R(a))-3,3',4,5'-tetramethoxy-4,5-methylenedioxypyramidatin, and (R(a))-3,3',4,5-tetramethoxy-4',5'-methylenedioxypyramidatin are reported herein for the first time. In the current dataset, NMR values are in accordance with the observed and calculated CD values. These values are herein reported with particular reference to previously described data of pyramidatins, which have to be revised.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1873-3700
pubmed:author
pubmed:copyrightInfo
Copyright © 2010 Elsevier Ltd. All rights reserved.
pubmed:issnType
Electronic
pubmed:volume
71
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1787-95
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Dibenzocyclooctadiene lignans from Magnolia and Talauma (Magnoliaceae): their absolute configuration ascertained by circular dichroism and X-ray crystallography and re-evaluation of previously published pyramidatin structures.
pubmed:affiliation
Institute of Pharmaceutical Sciences, Department of Pharmacognosy, University of Graz, Graz, Austria. wolfgang.schuehly@uni-graz.at
pubmed:publicationType
Journal Article