6-O-Malonyl-β-methyl-d-glucopyranoside from roots of Rumex obtusifolius

Kasai, Takanori; Okuda, M.; Sakamura, Sadao

doi:10.1016/0031-9422(81)83043-9

Cited by 17 publications

(8 citation statements)

References 4 publications

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“…Several aspects of the phytochemistry of R. obtusifolius have been reported previously. These include the isolation and characterisation of α-picoline (Wilkinson, 1958), anthraquinones (Fairburn and Muhtadi, 1972) and glucopyranosides in roots (Kasai et al, 1981(Kasai et al, , 1982. However the structure of the proanthocyanidin has not previously been reported.…”

Section: Introductionmentioning

confidence: 99%

Isolation and Characterisation of Procyanidins from Rumex obtusifolius

Spencer

Sivakumaran

Fraser

et al. 2007

Phytochemical Analysis

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An acetone:water (7:3) extract obtained from the leaves of Rumex obtusifolius was fractionated into procyanidin oligomer and polymer fractions using a linear gradient and a simple step method on Sephadex LH-20. The chemical characteristics of the procyanidin fractions were studied by 13C-NMR spectroscopy, acid-catalysed degradation in the presence of benzyl mercaptan, matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) MS and electrospray ionisation (ESI) MS. The 13C-NMR showed that the polymer fraction consisted predominantly of procyanidin polymers, some with galloyl groups attached. The thiolysis reaction products indicated a mean degree of polymerisation (DP) of 4.3 for the step method, and a range of 2.3-8.2 mean DP for the gradient fractionation, with epicatechin as the most abundant flavan-3-ol extension unit, while the terminal units consisted of equal proportions of catechin, epicatechin and epicatechin gallate. Singly charged ions observed in MALDI-TOF/MS showed a range of oligomeric procyanidins and their polygalloyl derivatives. These species (in the range DP 2-7) were also observed by ESI/MS but the spectra were more complex due to overlapping multiply charged ions. Isolation of oligomers from the Sephadex LH-20 fraction by chromatography on polyamide and C18 yielded B1, B2, B3 and B7 dimers, an A-type trimer and a B2 3,3'-O-digallate.

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Section: Introductionmentioning

confidence: 99%

Isolation and Characterisation of Procyanidins from Rumex obtusifolius

Spencer

Sivakumaran

Fraser

et al. 2007

Phytochemical Analysis

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“…XX was prepared, according to the methods of Nishikawa et al (1975), from the silver salt of VIII and acetobromogentiobiose in dry, alcohol-free chloroform. The malonylglucoside conjugate (XIX) was prepared, according to the methods of Kasai et al (1981), from malonic acid and XVIII in the presence of IV^V-dicyclohexylcarbodiimide in dry dioxane.…”

Section: Introductionmentioning

confidence: 99%

Metabolism of the synthetic pyrethroid fenpropathrin in plants

Mikami¹,

Baba²,

Katagi³

et al. 1985

J. Agric. Food Chem.

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The metabolic fate of fenpropathrin [(i?S)-a-cyano-3-phenoxybenzyl 2,2,3,3-tetramethylcyclopropanecarboxylate] in cabbages was studied by using 14C preparations labeled separately at the cyano group and the benzyl and cyclopropyl rings. By foliar treatment in a greenhouse, the insecticide disappeared with the the initial half-life of approximately 11-12 days. The insecticide underwent ester cleavage, hydroxylation at either or both of the gem-dimethyl groups with subsequent oxidation to the carboxylic acid, hydroxylation at the 2or 4-position of the phenoxy group, and hydrolysis of the CN group to the CONH2 and COOH groups. Most of the carboxylic acids and alcohols thus produced occurred as glycoside conjugates. 2,2,3,3-Tetramethylcyclopropanecarboxylic acid, the acidic half of the molecule, was converted mainly to glucose conjugate in abscised leaves of apple and vine, to malonylglucoside in cabbage, orange, and bean plants, and to gentiobioside in tomato. H14CN in abscised leaves of cabbage was rapidly incorporated into /3-cyanoalanine, asparagine, aspartic acid, and 7-glutamyl-/3-cyanoalanine, with ultimate formation of 14C02 and bound 14C residues. Little 14C was detected in the shoot portions of bean plants grown to maturity in soils treated with 14C-fenpropathrin at a rate of 1 ppm.

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“…4 and Table). A sugar moiety was noted again and was indicated to be a 6'-O-malonyl-bglucopyranoside group, by comparison of the 1 H and 13 C shifts with 6-O-malonyl-bmethyl-d-glucopyranoside [30]. The indicated site of attachment for the peripheral glucopyranosyl substituent (C( 8 2 )) and the bridging oxygen O( 8 3 ) were consistent also with the typical downfield shifts of the H-NMR spectra of 6a in CD 3 OH, two additional signals were detected at 3.80 ppm, due to CH (13 2 ), and at 3.22 ppm, due to the malonate CH 2 group.…”

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confidence: 99%

Chlorophyll Breakdown in Tobacco: On the Structure of Two Nonfluorescent Chlorophyll Catabolites

Berghold

Eichmüller

Hörtensteiner

et al. 2004

Chemistry & Biodiversity

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In extracts of senescent leaves of the tobacco plant Nicotiana rustica, two colorless compounds with UV/VIS characteristics of nonfluorescent chlorophyll catabolites (NCCs) were detected and tentatively identified as Nr-NCCs. These two polar NCCs were found in similar amounts in the fresh extracts, and their constitutions could be determined by spectroscopic analysis. The data showed both of the two Nr-NCCs to have the same tetrapyrrolic core structure, as reported previously for all other NCCs from senescent higher plants. In the less polar catabolite, named Nr-NCC-2, this core structure was conjugated with a glucopyranose unit, as similarly discovered earlier in Bn-NCC-2, an NCC from oilseed rape (Brassica napus). The more polar NCC from tobacco leaves, Nr-NCC-1, carried an additional malonyl substituent at the 6'-OH group of the glucopyranosyl moiety. Partial (enzyme-catalyzed) hydrolysis of Nr-NCC-1 gave Nr-NCC-2, while enzyme-catalyzed malonylation of Nr-NCC-2 gave Nr-NCC-1, establishing the identity of their basic tetrapyrrole structure. In earlier work (on the polar NCCs from oilseed rape), only separate glucopyranosyl and malonyl functionalities were detected. Nr-NCC-1, thus, represents a further variant of the structures of NCCs from senescent higher plants and exhibits an unprecedented peripheral refunctionalization in chlorophyll catabolites.

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6-O-Malonyl-β-methyl-d-glucopyranoside from roots of Rumex obtusifolius

Cited by 17 publications

References 4 publications

Isolation and Characterisation of Procyanidins from Rumex obtusifolius

Isolation and Characterisation of Procyanidins from Rumex obtusifolius

Metabolism of the synthetic pyrethroid fenpropathrin in plants

Chlorophyll Breakdown in Tobacco: On the Structure of Two Nonfluorescent Chlorophyll Catabolites

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