A prenylated xanthone from cell suspension cultures of Hypericum patulum

Ishiguro, Kyoko; Nagareya, Noriko; Suitani, Akiko; Fukumoto, Hisae

doi:10.1016/s0031-9422(96)00651-6

Cited by 21 publications

(13 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the basis of the biosynthetic hypothesis of Quillinan and Scheinmann (15), compound 1a could arise from tris(dimethylallyloxy) precursor 17a, the xanthone motif of which could be traced to 1,3,5,6-tetrahydroxyxanthone 18. It is of interest to mention that 18 is also a natural product found in plants of the genus Hypericum (Guttiferae) (19,20). Further disconnection across the central ring of xanthone 18 unveils phloroglucinol (19) and 2,3,4-trihydroxybenzoic acid as suitable starting materials.…”

Section: Resultsmentioning

confidence: 99%

Unified synthesis of caged Garcinia natural products based on a site-selective Claisen/Diels–Alder/Claisen rearrangement

Tisdale

Slobodov

Theodorakis

2004

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

A unified synthetic strategy toward caged Garcinia natural products has been designed and implemented. Central to the strategy is a tandem Claisen͞Diels-Alder͞Claisen rearrangement of a suitably substituted xanthone precursor to form forbesione (1a). Serving as a template, forbesione is then used to deliver representative members of this family, including desoxygaudichaudione A (4), desoxymorellin (5), and gambogin (10). Studies on the timing of this reaction cascade suggest that the C-ring Claisen͞Diels-Alder rearrangement proceeds initially and is followed by the A-ring Claisen reaction. The electronic and steric effects that govern the outcome of this cascade are presented.

show abstract

Section: Resultsmentioning

confidence: 99%

Unified synthesis of caged Garcinia natural products based on a site-selective Claisen/Diels–Alder/Claisen rearrangement

Tisdale

Slobodov

Theodorakis

2004

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…This may be because of mutual effects of the chemical constituents in Tianjihuang extract. A variety of compounds have been isolated from Tianjihuang, including flavonoids (Wu et al, 1998;Ishiguro et al, 1991bIshiguro et al, , 1993, phloroglucinol derivatives (Hu et al, 2000), xanthonoids (Ishiguro et al, 1997), chromone glycosides (Wu et al, 1998;Ishiguro et al, 1990) and peptides (Ishiguro et al, 1991a). Its active components are complicated.…”

Section: Pharmacokinetic Studymentioning

confidence: 99%

“…(Chinese name, Tianjihuang) has been used as a Chinese medicinal herb for the treatment of infectious hepatitis, bacterial diseases and tumors for many years (Hu et al, 1996;Ishiguro et al, 1986;Wu et al, 1998;Li et al, 1993). Previous phytochemical studies of Tianjihuang have demonstrated that it mainly contains flavonoids (Wu et al, 1998;Ishiguro et al, 1991bIshiguro et al, , 1993, phloroglucinol derivatives (Hu et al, 2000), xanthonoids (Ishiguro et al, 1997), chromone glycosides (Wu et al, 1998;Ishiguro et al, 1990) and peptides (Ishiguro et al, 1991a). The isolated compounds were tested for their coagulant activity in in vitro systems.…”

Section: Introductionmentioning

confidence: 99%

HPLC analysis and pharmacokinetic study of quercitrin and isoquercitrin in rat plasma after administration of Hypericum japonicum thunb. extract

Wang

Zhang

et al. 2007

Biomedical Chromatography

View full text Add to dashboard Cite

A simple HPLC method was developed for determination of quercitrin and isoquercitrin in rat plasma. Reversed-phase HPLC was employed for the quantitative analysis using kaempferol-3-O-beta-D-glucopyranoside-7-O-alpha-L-rhamnoside as an internal standard. Following extraction from the plasma samples with ethyl acetate-isopropanol (95:5, v/v), these two compounds were successfully separated on a Luna C(18) column (250 x 4.6 mm, 5 microm) with isocratic elution of acetonitrile-0.5% aqueous acetic acid (17:83, v/v) as the mobile phase. The flow-rate was set at 1 mL/min and the eluent was detected at 350 nm for both quercitrin and isoquercitrin. The method was linear over the studied ranges of 50-6000 and 50-5000 ng/mL for quercitrin and isoquercitrin, respectively. The intra- and inter-day precisions of the analysis were better than 13.1 and 13.2%, respectively. The lower limits of quantitation for quercitrin and isoquercitrin in plasma were both of 50 ng/mL. The mean extraction recoveries were 73 and 61% for quercitrin and isoquercitrin, respectively. The validated method was successfully applied to pharmacokinetic studies of the two analytes in rat plasma after the oral administration of Hypericum japonicum thunb. ethanol extract.

show abstract

“…This involves the condensation of shikimate and acetate-derived moieties to form benzophenones or benzophenone-like intermediates, which then react intramolecularly to form xanthones. Mechanisms for this intramolecular reaction have been postulated involving either direct phenol oxidative coupling (Lewis, 1963), quinone addition (Ellis et al, 1967), dehydration Norcowanin (227) Garcinia cowa [280] 6-Methoxykielcorin (228) Hypericum re¯exum [53] Isocadensin D (229) Psorospermum febrifugum [2] Cadensin F (230) Psorospermum febrifugum [2] Isocadensin D Ð monoacetate (231) Psorospermum febrifugum [2] Paxanthonin (232) Hypericum patulum [176,179] 1,2-Dihydro-3,6,8-trihydroxy-1,1-bis(3-methylbut-2-enyl)xanthen-2,9dione (233) Hypericum patulum [178] Muraxanthone (234) Seneico mikanioides [60] Table 6 (continued) between hydroxyl groups on the acetate and shikimatederived rings , or spirodienone formation and subsequent rearrangement to form the xanthone (Gottlieb, 1968;.…”

Section: -O-demethylpaxanthonin (215)mentioning

confidence: 99%

Tetraoxygenated naturally occurring xanthones

2000

View full text Add to dashboard Cite

This review, with 350 references, gives information on the chemical study of 234 naturally occurring tetraoxygenated xanthones in 12 families, 53 genus and 182 species of higher plants, and two which are described as fungal and lichen metabolites. The value of these groups of substances in connection with pharmacological activity and therapeutic use of some species is described. The structural formulas of 135 isolated compounds, and their distribution, are also given.

show abstract

A prenylated xanthone from cell suspension cultures of Hypericum patulum

Cited by 21 publications

References 10 publications

Unified synthesis of caged Garcinia natural products based on a site-selective Claisen/Diels–Alder/Claisen rearrangement

Unified synthesis of caged Garcinia natural products based on a site-selective Claisen/Diels–Alder/Claisen rearrangement

HPLC analysis and pharmacokinetic study of quercitrin and isoquercitrin in rat plasma after administration of Hypericum japonicum thunb. extract

Tetraoxygenated naturally occurring xanthones

Contact Info

Product

Resources

About