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【期刊论文】Conyzasaponins I-Q, Nine New Triterpenoid Saponins from Conyza blinii
果德安, Yanfang Su, †, ‡, Kazuo Koike, Tamotsu Nikaido, *, Jiansheng Liu, §, Junhua Zheng, § and Dean Guo*
J. Nat. Prod. 2003, 66, 1593-1599,-0001,():
-1年11月30日
Nine new triterpenoid saponins, conyzasaponins I-Q (1-9), were isolated from the aerial parts of Conyza blinii. Their structures were established on the basis of extensive 1D and 2D NMR spectra as well as by chemical degradations. Among these compounds, conyzasaponins M-O (5-7) share a common pentasaccharide unit attached to C-28 of the aglycon, 28-O-β-D-apiofuranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-[β-D-apiofuranosyl-(1→3)]-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl ester, which contains two apiofuranosyl residues. To the best of our knowledge, they are among the few examples of natural products possessing two apiofuranose units in a single sugar chain.
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【期刊论文】Directional Modifications of Resibufogenin by Mucor subtilissimus and Pseudomonas aeruginosa
果德安, JIXUN ZHAN a, b, YUANXING ZHANG b, WENHUI LIU a, HONGZHU GUO a AND DEAN GUO a*
Biocatalysis and Biotransformation, 2003 VOL. 21 (3). pp. 141-143,-0001,():
-1年11月30日
Directional modifications of resibufogenin 1 by Mucor subtilissimus and Pseudomonas aeruginosa were carried out. The substrate was hydroxylated at C-12 by M. subtilissimus AS 3.2454, from which a major product 12-hydroxyresibufogenin 2 was obtained. Then product 2 was dehydrogenated by P. aeruginosa AS 1.860, which resulted in a new compound 12β-hydroxy-3-keto-resibufogenin 3.
Directional modifications, Resibufogenin, Hydroxylation, Mucor subtilissimus, Dehydrogenation, Pseudomonas aeruginosa
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果德安, Lie Li, Jin-Lan Zhang, Yu-Xin Sheng, Guan Ye, Hong-Zhu Guo, De-An Guo*
Journal of Chromatography B, 808(2004)177-183,-0001,():
-1年11月30日
Four major active saponins (ginsenosides Rg1, Rb1, Rd and notoginsenoside R1) in Panax notoginseng were determined in rat urine after oral and intravenous administration of total saponins of P. notoginseng (PNS), and the urine samples were treated with solid-phase extraction (SPE) prior to liquid chromatography. A reversed-phase liquid chromatography system with ultraviolet detection and a Zorbax SB-C18 column was used. The within-day and between-day assay coefficients of variation for the four saponins in urine were less than 7% and the recovery of this method was higher than 85%. Using this method, the excretion profile of the drug in rat urine after administration of PNS was revealed for the first time.
Panax notoginseng, Saponins, Ginsenosides
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果德安, Yuxin Sheng, Lie Li, Chuanshe Wang, Yanyan Li, Dean Guo*
Journal of Chromatography B, 806(2004)127-132,-0001,():
-1年11月30日
A sensitive and rapid high-performance liquid chromatography (HPLC) method with solid-phase extraction (SPE) to simultaneously determine albiflorin and paeoniflorin in rat serum was described. Serum samples were pretreated with solid-phase extraction using Extract-CleanTM cartridges, and the extracts were analyzed by HPLC on a reversed-phase C18 column and a mobile phase of acetonitrile-0.03% formic acid (17:83 (v/v)) with ultraviolet detection at 230nm. Pentoxifylline was used as the internal standard (IS). The linear ranges of the calibration curves were 29-1450ng/ml for albiflorin and 10-2000ng/ml for paeoniflorin. The intra-and inter-day precisions (R.S.D.) were≤10.49% for albiflorin and≤11.29% for paeoniflorin, respectively. Mean recovery was determined to be 89.75% for albiflorin and 85.82% for paeoniflorin. The limit of quantification was 29ng/ml for albiflorin and 10ng/ml for paeoniflorin, respectively. The validated method was applicable to pharmacokinetic studies of albiflorin and paeoniflorin from rat serum after oral administration of Si-Wu decoction. The pharmacokinetic study indicated that albiflorin and paeoniflorin had poor absorption and rapid elimination. This assay result was necessary for the pharmacokinetic evaluation of Si-Wu decoction.
Albiflorin, Paeoniflorin
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果德安, Min Ye, Guiqin Qu, Hongzhu Guo, Dean Guo*
Journal of Steroid Biochemistry & Molecular Biology 91(2004)87-98,-0001,():
-1年11月30日
Microbial transformation was used to prepare novel cytotoxic bufadienolides. Twelve products (3-14) were obtained from bufalin (1) by the fungus Mucor spinosus. Their structures were elucidated by high-resolution mass spectroscopy (HR-MS) and extensive NMR techniques, including 1H NMR, 13C NMR, DEPT, 1H-1H correlation spectroscopy (COSY), two dimensional nuclear Overhauser effect correlation spectroscopy (NOESY), heteronuclear multiple quantum coherence (HMQC), and heteronuclear multiple bond coherence (HMBC). Compounds 3, 4, 9 and 11-14 are new mono-or dihydroxylated derivatives of bufalin with novel oxyfunctionalities at C-1β, C-7β, C-11β, C-12β and C-16α positions. The in vitro cytotoxic activities against human cancer cell lines of 3-14, together with 16 biotransformed products derived from cinobufagin (15-30) were determined by the MTT method, and their structure-activity relationships (SAR) were discussed.
Bufalin, Bufadienolide, Microbial transformation, Mucor spinosus, Cytotoxicity, Structure-activity relationship
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