Neolignan glycosides from roots of Codonopsis tangshen

Yuda, Masamichi; Ohtani, Kazuhiro; Mizutani, Kenji; Kasai, Ryoji; Tanaka, Osamu; Wang, Tingyun; Yi-rui, Ling; Pu, Xui-Feng; Saruwatari, Yuhichiro

doi:10.1016/0031-9422(90)85053-i

Cited by 52 publications

(31 citation statements)

References 9 publications

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“…[21] Oxidation at position 3 was shown to be the only reaction observed with substrates 24, 25 and 26. Although 2-deoxy-dglucose (24) does not possess an oxidisable hydroxyl group in position 2, it is oxidised with considerable efficiency (Table 1) to the 3-keto compound 27.…”

Section: Resultsmentioning

confidence: 99%

“…We thus isolated (1 36)-linked disaccharides 36, [24] 37, [25] 38 and 40 [26] in yields between 7 and 20 % in addition to minor amounts of (1 33)-linked disaccharides 39 and 41 which Table 1. Kinetic data of enzymatic oxidations with immobilised pyranose 2-oxidase.…”

Section: Resultsmentioning

confidence: 99%

“…This demonstrates that the pentulose 28 as well as the C-1 oxidation products 29, 53 and 54 are formed by chemical oxidation with H 2 O 2 , which is produced during the enzymatic reaction (or with O 2 from the bubbling air ). We assume that the C-1 oxidated derivatives 29, 53, and 54 are formed by direct chemical oxidation of 2-deoxy-d-glucose (24), by H 2 O 2 (or with O 2 from the bubbling air), which is in agreement with the usual chemical oxidation of 2-deoxy-dglucose. [50,51] On the other hand, the product 28 may be formed by subsequent chemical oxidation of enzymatically oxidised 27.…”

Section: Substratementioning

confidence: 99%

“…The galacto derivative 31, on the other hand, exclusively adopts the usual hydrated form in water. [30] Enzymatic oxidation of 2-deoxy-d-glucose (24) gives the 3-keto derivative 27 (Scheme 7). Although 27 has been reported as a probable enzymatic oxidation product of 24, [7c] it has never been characterised or synthesised by chemical Scheme 7.…”

Section: Substratementioning

confidence: 99%

“…Although 27 has been reported as a probable enzymatic oxidation product of 24, [7c] it has never been characterised or synthesised by chemical Scheme 7. Enzymatic oxidation of 2-deoxy-d-glucose (24) to give the 3-keto derivative 27. means to our knowledge. Also, when we attempted a chemical synthesis of 27 from the glycoside 52 [47] this proved to be difficult.…”

Section: Substratementioning

confidence: 99%

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Rare Keto-Aldoses from Enzymatic Oxidation: Substrates and Oxidation Products of Pyranose 2-Oxidase

Freimund¹,

et al. 1998

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Pyranose oxidases are known to oxidise d-glucose, d-xylose and lsorbose to keto-aldoses, biochemically interesting compounds that may also be used for synthetic purposes in a variety of reactions. In this study pyranose oxidase from the basidiomycete Peniophora gigantea was investigated, and it was found that this enzyme is able to oxidise a broad variety of substrates very effectively. In analogy to its natural mode of action, most substrates are oxidised regioselectively in position 2. Certain compounds, however, are converted into 3-keto derivatives, and the enzyme even exhibits transfer potential, that is, disaccharides are formed from bglycosides of higher alcohols. Substrates that may be oxidised at C-2 in yields between 40 ± 98 % are d-allose, d-galactose, 6-deoxy-d-glucose, d-gentiobiose, a-d-glucopyranosyl fluoride and the very interesting 3-deoxy-d-glucose. 1,5-Anhydro-d-glucitol (1-deoxy-d-glucose) is very effectively oxidised in position 2 in 98 % yield and additionally gives a product of dioxidation at C-2 and C-3 upon prolonged reaction time. Selective oxidation at C-3 was found for 2-deoxyd-glucose in very good yields and for methyl b-d-gluco-and methyl b-galactopyranoside in lower yields. All oxidation products were unequivocally characterised by NMR spectroscopy and/or chemical derivatisation. In addition, the kinetic data of the enzymatic reactions were determined for all substrates. On the basis of these data and the structural characteristics of the substrates, a model for the minimal structural requirements of the enzyme ± substrate interaction is suggested. The enzyme presumably uses two different binding modes for the regioselective C-2 and the C-3 oxidations, which are described.

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Substratementioning

confidence: 99%

Section: Substratementioning

confidence: 99%

Section: Substratementioning

confidence: 99%

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Rare Keto-Aldoses from Enzymatic Oxidation: Substrates and Oxidation Products of Pyranose 2-Oxidase

Freimund¹,

et al. 1998

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Two New Phenylpropanoid Derivatives from Codonopsis tangshenOliv.

Song

Chou

Zhong

et al. 2008

Helvetica Chimica Acta

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Evaluation of surfactant‐assisted pressurized hot water extraction for marker compounds in Radix Codonopsis pilosula using liquid chromatography and liquid chromatography/electrospray ionization mass spectrometry

Ong

Len²

2003

J of Separation Science

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Evaluation of surfactant-assisted pressurized hot water extraction for marker compounds in Radix Codonopsis pilosula using liquid chromatography and liquid chromatography/electrospray ionization mass spectrometryIn the move towards the elimination of organic solvents in the extraction process in botanicals, a new method combining surfactant and pressurized hot water extraction (PWHE) with an applied temperature below the boiling point and lower pressure from 10 to 20 bar was developed for the analysis of marker compounds that are reasonably hydrophobic such as tetradeca-4E,12E-diene-8,10-diyne-1,6,7-triol and tetradeca-4E,12E-diene-8,10-diyne-1,6,7-triol-O-b-D-glucoside in Radix Codonopsis pilosula (DangShen). Because reference substances for the proposed botanicals were not available, a method was developed to isolate the marker compounds in Radix Codonopsis pilosula. Other than surfactant-assisted PHWE, the marker compounds present in Radix Codonopsis pilosula were extracted using pressurized liquid extraction (PLE) with methanol and PHWE with a mixture of water/ethanol (80:20). The extracts were analyzed using liquid chromatography and liquid chromatography/electrospray ionization mass spectrometry. With surfactant-assisted PHWE, the effects of different added surfactants such as sodium dodecyl sulfate and Triton X-100 was studied. Surfactant assisted PHWE with Triton X-100 proved to be at least equivalent or better compared to Soxhlet extraction in terms of quantitative analysis of marker compounds in Radix Codonopsis pilosula. The method precision was less than 8% (RSD, n = 6). The presence of surfactants in PHWE was found to enhance the solubility of target compounds naturally occurring in medicinal plants.

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Neolignan glycosides from roots of Codonopsis tangshen

Cited by 52 publications

References 9 publications

Rare Keto-Aldoses from Enzymatic Oxidation: Substrates and Oxidation Products of Pyranose 2-Oxidase

Rare Keto-Aldoses from Enzymatic Oxidation: Substrates and Oxidation Products of Pyranose 2-Oxidase

Two New Phenylpropanoid Derivatives from Codonopsis tangshenOliv.

Evaluation of surfactant‐assisted pressurized hot water extraction for marker compounds in Radix Codonopsis pilosula using liquid chromatography and liquid chromatography/electrospray ionization mass spectrometry

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