Showing papers in "Phytochemistry Letters in 2008"

TL;DR: The isolated compounds and other flavonoid glycoside analogues exhibited antifungal activity against different Fusarium oxysporum f.sp.

TL;DR: Theanine can be synthesised from glutamic acid and ethylamine derived from alanine in all parts of tea seedlings, however, supplied NH 3 exogenously to intact seedlings was converted to theanine mainly in roots.

TL;DR: Phytochemical techniques are developing fast and tools available which allow for a systematic investigation of complex mixtures and specifically to link phytochemical analysis with other strategies (such as in vitro or in vivo screening for biological activity or toxicity, morphological plant diversity and ecological parameters).

TL;DR: Whereas GC/MS proved to be an appropriate tool for the study of specific expected metabolites of catechin stereoisomers, GC×GC-TOF-based metabolomics analysis also revealed new metabolites not included in the targeted analyses.

TL;DR: An analysis of the structure-activity relationship shows that the substituents in position C-1 and C-2 of aporphine alkaloids are crucial for the antimalarial activity.

TL;DR: In this article, eight known compounds, oleanolic acid (1), linoleic acid (3), linolenic acid, betulin (5), betulinic acid(6), 5-(hydroxymethyl)-2-furfural (7), and β-sitosterol were isolated from an hexane-soluble partition of a methanol extract of Thompson seedless raisins (Vitis vinifera).

TL;DR: A series of eleven biflavonoids containing amentoflavone and hinokiflavone derivatives from the Indian medicinal herb Selaginella bryopteris has been investigated for their antiprotozoal activity using in vitro assays against the K1 strain of Plasmodium falciparum, Leishmania donovani, Trypanosoma brucei rhodesiense and TryPanosoma cruzi.

TL;DR: Phytochemical investigation of Hypericum empetrifolium Willd.

TL;DR: In this paper, a phytochemical investigation of the methylene chloride/methanol extract of the aerial parts of Artemisia herba-alba afforded two new sesquiterpene lactones 1β,9β-diacetoxyeudesm-3-en-5α,6β,11β H -12,6-olide (1).

TL;DR: A new oleanane-type triterpene saponin, β- d -glucopyranosyl 2α,3β,6β-trihydroxy-23-galloylolean-12-en-28-oate (1), together with four known oleanANE-type pentacyclic triterpenoids, combregenin (2), arjungenin(3), ARJunglucoside I (4), and combreglucose (5) were isolated from the stem bark of Comb

TL;DR: Structural–activity relationships of flavonoids as intensifiers of INH susceptibility in mycobacteria indicate that they overlap with SARs for their radical-scavenging properties, however the potentiation of INh activity cannot only be explained by theirradical- scavenging activity alone.

TL;DR: Three new spermidine alkaloids were isolated from the roots of Capparis spinosa and their structures were established on the basis of spectroscopic analysis, including 1D and 2D NMR experiments.

TL;DR: Three xanthones, named cochinchinones E-G and G, together with 10 known Xanthones and a known anthraquinone were isolated from the root, fruit and twigs of Cratoxylum cochchinense as mentioned in this paper.

TL;DR: In this article, two new flavones: 5,7-dihydroxy-3-isoprenyl flavone (1 ) and 5,hydroxy- 3-ISOPrenyl Flavone (2 ), along with two known compounds β-sitosterol and stigmasterol have been isolated from the chloroform extract of Sida cordifolia.

TL;DR: A comprehensive phytochemical investigation of the rhizomes of Dryopteris crassirhizoma Nakai resulted in the isolation and identification of one new trimeric phloroglucinol, trisflavaspidic acid ABB (1) together with 12 known compounds as discussed by the authors.

TL;DR: It is shown for the first time, that some species of the family Marantaceae of the order Zingiberales accumulate rosmarinic acid, which was detected in two species of Maranta and one Thalia species.

TL;DR: Five new C15 eight-membered cyclic ethers with a characteristic terminal cis ene–yne moiety were isolated from the organic extract of the red alga Laurencia glandulifera, collected at Crete island in South Greece, by extensive analysis of their NMR spectra.

TL;DR: A chalcone, 2,3-dimethoxy-4′-γ,γ-dimethylallyloxy-2′-hydroxychalcone (1) and an isoflavone, 7 −γ, γ-dimethyltimethylally loxy-5 −hydroxy-4 −methoxyisoflavones (2) were isolated from the root bark of Dalbergia sissoo and the structures of these compounds were elucidated on the basis of spectral and chemical studies.

TL;DR: A degraded diterpenoid dimer and manniorthoquinone have been isolated from the stem bark of Neoboutonia mannii Benth and their structures were elucidated on the basis of spectral studies and comparison with published data.

TL;DR: NMR data for phyllanthol provided in the literature have been revised and the leaves of Phyllanthus polyanthus yielded (20 S )-3α-acetoxy-24-methylenedammaran-20-ol.

TL;DR: The structures of these coumarins were unequivocally determined by spectroscopic means, notably UV, HRESIMS, and 1D and 2D NMR spectroscopy as mentioned in this paper.

TL;DR: A novel isoflavan-4-ol (pumilanol) exhibited significant antiprotozoal activity against T. rhodensiense, T. cruzi and L. donovani, but displayed high toxicity towards L-6 (IC 50 of 17.12 μg/mL) rat skeletal myoblasts.

TL;DR: The roots of Dichapetalum madagascariensis have yielded the new dichapetalin M, which exhibited greater toxicity towards brine shrimp larvae than dichAPetalin A, which has demonstrated cell inhibition against various cancer cell lines.

TL;DR: In this article, an ethanolic extract of the aerial parts of Delphinium staphisagria L. from Tenerife yielded four new flavonol glycosides 2″-acetylastragalin, 2″acetylpaeonoside, quercetin 3-O-(2acetyl-β-glucopyranoside)-7-O-β -glocopyranoide and 2″ -acetylpetiolaroside in addition to astragalin, isoquercitrin, pae

TL;DR: In this article, two new isoprenylated flavanones, tonkinochromanes J (1 ) and K (2 ), and a new dihydrochalcone were isolated from the roots of Sophora tonkinensis along with four known compounds ( 4-7 ).

TL;DR: In this article, two new diterpenes, including one with an unprecedented 6/6/8 carbon ring skeleton and another with 19 carbons, were isolated from the radix of Curcuma wenyujin and elucidated on the basis of spectroscopic analysis, mainly NMR and MS.

TL;DR: The ethyl acetate extract of the aerial parts of Ajuga turkestanica afforded 6 neo-clerodane diterpenes, including two novel compounds, 14, 15-dihydroajugachin B and 14-hydro-15-methoxyajugaches B and chamaepitin, which were elucidated through exhaustive NMR spectroscopic analysis and chemical transformation.

TL;DR: Results indicate that methylation of xanthosine by 7-methylxanthosinesine synthase is the most plausible rate-limiting step of caffeine biosynthesis; the supply of non-methylated purine precursors or availability of S-adenosyl- l -methionine are not the principal controlling factors of coffee biosynthesis.

TL;DR: Phytochemical investigation of flowering tops of Leonotis leonurus yielded a new diterpene ester, 1,2,3-trihydroxy-3,7,11,15-tetramethylhexadecan-1-yl-palmitate along with five known metabolites that were determined by spectroscopic methods including 1D- and 2D NMR spectroscopy.

TL;DR: Results indicate that the presence of the acetoxy group has a detrimental effect on antibacterial activity against certain strains of Staphylococcus aureus.