New 5-Methylcoumarin derivatives from Ethulia conyzoides

Balbaa, S. I.; Halim, Ahmed F.; Halaweish, Fathi T.; Bohlmann, Ferdinand

doi:10.1016/0031-9422(80)80208-1

Cited by 8 publications

(8 citation statements)

References 6 publications

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“…Jedoch enthalten auch vier Gattungen der Tribus Vernonieae artige verbindungen3. 5,6,9.10,13,15,16) __ der-11 12 13 Die uberraschend groDe Zahl und Variationsbreite derartiger Verbindungen wirft die Frage nach ihrer Biogenese auf. Offensichtlich ist das 5-Methyl-4-hydroxycumarin eine zentrale Vorstufe, die wahrscheinlich durch Kondensation des Coenzym-A-Derivats von Methylsalicylsaure mit Malonyl-CoA gebildet wird, obwohl ein direkter Aufbau des Clo-Acetogenins nicht auszuschliel3en ist.…”

Section: -Methylcoumarin Derivatives From Lycoseris Iazifoliaunclassified

5‐Methylcumarin‐Derivate aus Lycoseris latifolia

et al. 1985

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Aus oberirdischen Teilen von Lycoseris latifolia wurden neun Cumarin-Derivate isoliert, die sehr wahrscheinlich biogenetisch durch Kondensation von 4-Hydroxy-5-methylcumarin mit einem Sesquiterpenaldehyd gebildet werden, wonach sich verschiedene Umwandlungen und Abbaureaktionen anschlieBen. Die Strukturen wurden durch Hochfeld-NMR-Spektroskopie geklart. NOE-Differenzspektroskopie ermoglichte eine eindeutige Zuordnung aller Konfigurationen. Die chemotaxonomische Bedeutung dieser Verbindungen wird kurz diskutiert. 5-Methylcoumarin Derivatives from Lycoseris IazifoliaFrom the aerial parts of Lycoseris ZatijoZia nine coumarin derivatives were isolated which most likely are formed biogenetically by condensation of 4-hydroxy-5-methylcoumarin with a sesquiterpene aldehyde followed by various transformations and degradations. The structures were elucidated by high-field NMR spectroscopy. NOE difference spectroscopy allowed an unequivocal assignment of all configurations. The chemotaxonomic relevance of these compounds is discussed briefly.Die Gattung Lycoseris (Compositae, Tribus Mutisieae, Subtribus Gochnatiinae) umfal3t 15 Arten, die von Costa Rica bis Peru verbreitet sind. Uber ihre verwandtschaftlichen Beziehungen zu anderen Gattungen ist noch kaum etwas bekannt, und chemische Untersuchungen fehlen. Wir haben daher einen in Costa Rica heimischen Vertreter, Lycoseris latifolia (D. Don.) Benth., naher untersucht.Aus oberirdischen Teilen haben wir neben y-Cadinen, p-Selinen und Lupeol ein komplexes Gemisch von Verbindungen isoliert, dessen Auftrennung erhebliche Schwierigkeiten bereitete. Das 'H-NMR-Spektrum des Gemisches zeigt charakteristische Signale, die wir bei verschiedenen 5-Methylcumarinen beobachtet haben. Weiterhin beobachtet man Signale fur phenolische Hydroxygruppen, wahrend Methoxysignale fehlen. Wir haben daher das Gemisch mit Diazomethan behandelt, da Vorversuche gezeigt haben, daB die entsprechenden Methylether besser trennbar sind. Nach mehrfacher dunnschichtchromatographischer Trennung sowie teilweise durch Hochdruckflussigchromatographie wurden schliel3lich zehn einheitliche Substanzen sowie ein Epimerengemisch erhalten.Die am wenigsten polare Verbindung ist ein Methoxy-Derivat und somit ein Methylierungsprodukt eines der Naturstoffe. Hochauflosende Massenspektro-

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Section: -Methylcoumarin Derivatives From Lycoseris Iazifoliaunclassified

5‐Methylcumarin‐Derivate aus Lycoseris latifolia

et al. 1985

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“…R' = H, R2 = O H (377) R' = OMe, R2 = OH (378) R' = R2 = R' = H, R2 = O H (382) R' = H, R2 = O H (380) R' = OMe R2 = OH (381) R' = R2 = H (383) R' = OMe, R2 = O H (384) R' = R2 = H~g a l l o c h a . ~~~Replacement by isoeugenol (384)3423 343 gave propacin(378), from Protium o p ~c u m , ~~~ the regioisomer (381) of which has been obtained in optically active form from…”

mentioning

confidence: 99%

Coumarins

Murray¹

1989

Nat. Prod. Rep.

122

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“…The chromatographic separation of the plant extracts and the spectral analysis of the separated compounds revealed the identification of the triterpenoids lupyl acetate [20] and was previously isolated from the same plant species [13] and lupeol [21]) that was isolated before from E. conyzoides [13], The monoterperpenoidal 5-methylcoumarins ethuliacoumarin (1) which was isolated previously from the same plant species by Baldaa et al, (1980) and [8,9], isoethyliacoumarin A (2) and isoethuliacoumarin C (3) which were isolated previously from the same plant species by (Baldaa et al, 1980) [8], as well as the flavonoid 7-O-methyl apigenin (Genkwanin) [22], which has not been isolated previously from E. conyzoides.…”

Section: Resultsmentioning

confidence: 99%

“…The molluscicidal activity of E. conyzoides was recorded [4], which was attributed to the presence of ethuliacoumarin A and isoethuliacoumarin A. The previous phytochemical screening revealed that E. conyzoides contains terpenoid 5-methylcoumarins [5,8,9,10,11,12], triterpenoids [13,14], flavonoids [15] and sterols [13]. This article presents the results of phytochemical and acaricidal activity investigation of E. conyzoides.…”

Section: Introductionmentioning

confidence: 99%

Acaricidal Activity of Ethulia conyzoides Extracts and Constituents against Tetranychus urticae Koch

Dawidar¹,

Abdel-Mogib²,

El-Naggar³

et al. 2015

IJSEA

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Abstract:The acaricidal potential of Ethulia conyzoides L. aerial parts extracts as well as its isolated compounds were investigated against larvae and adults of Tetranychus urticae Koch under laboratory conditions. Chromatographic separation of the extracts gave 3-O-acetyl lupeol, lupan-3-ol, ethuliacoumarin (1) and 7-O-methyl apigenin (Genkwanin), besides a mixture of isoethyliacoumarin A (2), isoethuliacoumarin C (3). The biological evaluation results indicated that ethyl acetate fraction and ethuliacoumarin (1) were the most potent to larvae and adults of Tetranychus urticae. The LC50 values of ethyl acetate fraction were found to be 11.58 and 17.86 ppm, respectively and LC50 values of (1) were found to be 12.72 and 19.22 ppm, respectively after 7 days of treatment.

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New 5-Methylcoumarin derivatives from Ethulia conyzoides

Cited by 8 publications

References 6 publications

5‐Methylcumarin‐Derivate aus Lycoseris latifolia

5‐Methylcumarin‐Derivate aus Lycoseris latifolia

Coumarins

Acaricidal Activity of Ethulia conyzoides Extracts and Constituents against Tetranychus urticae Koch

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