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The fat of the seeds from the West African tree Pycnanthus kombo contains ca 20% of a hitherto undescribed compound. This compound was identified as 16(2′,5′-dihydroxy-3′-methylphenyl)-2,6,10,14-tetramethyl-2,6,10,14-hexadecatetraenoic acid, for which the name kombic acid is proposed.  相似文献   
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Summary Females and males of three tree species did not differ in growth or mortality over an interval of 9.5 years. Comparing between sexes and across species, there was no consistent pattern of effects of short-term (1 year) growth and fecundity on longer-term gorwth or mortality. Effects of size were significant (but minor) for growth in one species, and were significant for mortality in two species. Soil type affected mortality in one species, but affected growth in all three species. Sex and size are not consistently strong bases for predicting the performance of adult trees.  相似文献   
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The constituents of Virola carinata were established as dehydrodieugenol, its monomethyl ether and sitosterol.  相似文献   
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The trunk woods of two Amazonian Myristicaceae, Virola minutiflora and V. elongata, contain respectively 1-(2-hydroxy-4-methoxyphenyl)-3-(3,4-m  相似文献   
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Eight highly polymorphic microsatellite loci were developed for Virola flexuosa from a (CA)n‐enriched genomic library for population and seed dispersal studies in eastern Ecuador. Loci show a high level of variation with the number of alleles ranging from 13 to 27. Observed and expected heterozygosities were from 0.313 to 0.896 and 0.552 to 0.937, respectively. The high levels of polymorphism and exclusionary power of the developed markers will likely prove very useful in direct measurement of seed dispersal.  相似文献   
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Dibenzylbutane and aryltetralone lignans from seeds of Virola sebifera   总被引:2,自引:0,他引:2  
Rezende KR  Kato MJ 《Phytochemistry》2002,61(4):427-432
Two lignans rel-(8R, 8'R)-3,4:3',4'-bis-(methylenedioxy)-7.7'-dioxo-lignan and (7'R,8'S,8S)-2'-hydroxy-3,4:4',5'-bis-(methylenedioxy)-7-oxo-2,7'-cyclolignan were isolated from seeds of Virola sebifera. The cyclolignan showed two atropisomers as determined by 1H NMR spectroscopy at low temperature.  相似文献   
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The fruits of Virola carinata contain the lignans (?)-cubebin, (?)-hinokinin and (+)-asarinin, besides four neolignans of the β-aryloxy-arylpropane type and two neolignans of the benzodioxane (eusiderin) type.  相似文献   
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Bark of Virola sebifera used in the preparation of hallucinogenic snuffs and drinks in Venezuela has yielded N-methyl-N-formyltryptamine and N-methyl-N-acetyltryptamine, which exist in two rotameric forms reflecting hindered rotation around the carbon—nitrogen bond of the amide function. They were detected by HPLC as well as NMR. 2-Methyl-1,2,3,4-tetrahydro-β-carboline, N,N-dimethyltryptamine, its oxide and N-monomethyltryptamine were also identified.  相似文献   
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