ChemInform Abstract: NATURALLY OCCURRING TERPENE DERIVATIVES. 98. CONSTITUENTS OF THE GENUS LIGULARIA

Abstract

Die Untersuchung von 13 Ligularia‐Arten ergibt neben bekannten Verbindungen die sieben neuen Sesquiterpene (I)‐(V).

Effects of a Labdane Diterpene Isolated from Brickellia paniculata on Intracellular Ca2+ Deposit of Guinea-Pig Ileal Longitudinal Muscle

“…In a previous study, from the methanolic extract were isolated a flavonoid (xanthomicrol) and a labdane diterpene, this latter compound was structurally characterized as 3a-angeloyloxy-2a-hydroxy-13,14Z-dehydrocativic acid (AAHDD) [3]. The structures have already been reported and their identity was confirmed by comparison with published physical and spectroscopic data [4], [5], [6]. Both compounds relaxed the segments of isolated guinea-pig ileum stimulated with high K + and the effect was correlated with an interference of Ca 2+ mobilization in the cell.…”

Inhibitory Effect of Xanthomicrol and 3α-Angeloyloxy-2α-hydroxy-13,14Z-dehydrocativic Acid from Brickellia paniculata on the Contractility of Guinea-Pig Ileum

“…From F 1 a solid was precipitated and after washing it with hexane, 0.5 % of pure compound 1 was obtained; from F 2 precipitated compound 2, yield 1.38 %. The identities of both compounds were confirmed by comparison with published physical and spectroscopic data [3], [4], [10]. For the biological assay, the distal guinea-pig ileum was removed and segments of 1.5 cm were suspended in 10 mL organ baths containing Tyrode solution at 37 8C bubbled with 95 % O 2 -5 % CO 2 and at a resting tension of 1 g. Contractility of the tissue was recorded isometrically using a Grass force-displacement transducer (FTO3C) connected to a Grass-7D polygraph.…”

“…The main purpose of the present report was to carry out bioguided fractionation of this extract and evaluation of the active principles. While monitoring the inhibitory effect produced by the fractions on the contractile responses induced with K + (60 mM), attention was focused on two major constituents: compound 1, which was characterized as the flavone 5,4¢-dihydroxy-6,7,8-trimethoxyflavone (xanthomicrol) and compound 2 as the labdane diterpene 3a-angeloyloxy-2a-hydroxy-13,14Z-dehydrocativic acid (AAHDD), both already isolated from the Brickellia species [3], [4]. Stimulation of most smooth muscles by high external K + concentrations induces a biphasic contractile response consisting of an initial rapid, highly transitory increase in tension (phasic component) followed by a slow sustained tonic contractile response.…”

Terpenoids and Related Compounds from Plants of the Family Compositae (Asteraceae)

“…: Ligularia dentata Hara has lon g been used as a medicinal herb for easing br eathing, stimulating blood flow, reducing in flammation, alleviating pain, stopping coughs, and getting rid of phlegm in China. Previous phytochemical investigations of this plant r esulted in the isolation of ph enolic norsesquiterpenoids [13][14][15], bisabolane-type sesquiterpenoids [16,17] and pyrrolizidine alkaloids [18]. On the other hand, fractionation of the ether extract of the leaves of this plant resu lted in the is olation of two synthetic known triterpenoids, (2E,6E,10E,14E,18E) [31], and a new cycloartane-type triterpenoid, 24-chlorocycloart-25-en-3-ol (36) (Figure 7) [27,32].…”

“…: Ligularia dentata Hara has lon g been used as a medicinal herb for easing br eathing, stimulating blood flow, reducing in flammation, alleviating pain, stopping coughs, and getting rid of phlegm in China. Previous phytochemical investigations of this plant r esulted in the isolation of ph enolic norsesquiterpenoids [13][14][15], bisabolane-type sesquiterpenoids [16,17] and pyrrolizidine alkaloids [18]. A new eudesmane-ty pe sesquiterpenoid, eudesma-4,11-diene-1,14-diol ( 21) [20], three n ew phenolic n orsesquiterpenoids, named liguladentanorol ( 22), 8-hydroxyligudentatol ( 23) and 8-hydroxyligujapone ( 24) [22], and two new lacton e derivatives, 2-acetoxy-2,3-dimethyl-5-methoxycarbonyl-9-methoxy-5heptanolide ( 25) and 2 -ethyl-5-hydroxy-5-methoxycarbonyl-4methyl-4-hexanolide (26), were isolated from the extract of this plant together with (2E,4R,5S)-2-ethylidene-5-methoxycarbonyl-4methyl-5-hexanolide ( 27), a known synthetic compound (Figure 5) [19].…”