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Panaxatriol, a triterpene bearing a steroid-like structure similar to cardiac glycosides, was presumed to share the same bioactivity with cardiac glycosides, and may be a potential Na+, K+-ATPase inhibitor. In this paper, a series of panaxatriol derivatives were synthesized and evaluated for Na+, K+-ATPase inhibitory activities. The results of biological tests showed that more than half of the synthesized derivatives presented increased inhibitory activities compared with panaxatriol. Of these compounds, 13a with a 3, 4-seco skeleton showed the most potent inhibitory activity, which was equal to that of the standard drug digoxin. To understand the binding mode of the most active compound, molecular docking study of 13a with Na+, K+-ATPase was conducted. Therefore, 13a may serve as a new lead compound for the development of novel Na+, K+-ATPase inhibitors.

Five new prenylated chalcones hedysarumines C-G (1-5), along with eight known chalcones (6-13) all of which were isolated from the genus Hedysarum for the first time, were isolated from the roots of Hedysarum gmelinii by chromatographic methods. Their structures were determined by extensive spectroscopic techniques. The isolated chalcones (2-13) and previously isolated prenylated chalcones (14-16) were evaluated for antiproliferative activity against five human cancer cell lines (HepG2, A549, Du145, BGC823, and HCT116) and in vitro anti-inflammatory activity. Compounds 5, 10, and 15 inhibited NO production induced by lipopolysaccharide in BV-2 cells, with IC

Six new compounds, including four new lignans, dipsalignan A (1), B–D (3–5), and two new bis-iridoid glycoside dimmers, dipsanosides M (7) and N (8), together with two known compounds (2) and (6), have been isolated from the roots of Dipsacus asper Wall. Their structures were established on the basis of spectroscopic data (MS, 1D, 2D NMR, and CD) and chemical methods. All the isolated compounds were tested against human immunodeficiency virus-1 (HIV-1) integrase inhibition activities, and only compounds 1, 2, 7, and 8 displayed weak activities.

Similisines A (1a) and B (1b), a pair of unprecedented polybrominated spiro-trisindole enantiomers fused through a five-member ring, along with seven known biologically related indole alkaloids, were isolated from Laurencia similis. The structures and absolute configurations of the enantiomers were elucidated by comprehensive spectroscopic analysis, computer modeling, and comparison of experimental and theoretically calculated ECD. The proposed biogenetic pathway of 1a and 1b and cytotoxic activity of all isolates were also discussed.

Novel thiophosphoramidate derivatives of nucleoside analogue as membrane-soluble prodrugs of the bioactive free nucleotides have been prepared by thiophosphorylation reaction. 2′,3′-O, O′-Isopropylidene uridine-5′-yl N-thiophosphoryl serine and threonine methyl esters underwent the intramolecular catalyzed hydrolysis reaction.

Novel alkyl thiophosphoramidate derivatives of nucleoside analogues (5) have been prepared by phosphochloridothioate chemistry. O-Isopropyl 2′, 3′-O-isopropylidene uridine-5′-yl N-thiophosphoryl threonine and serine methyl esters (Sa and 5b) underwent the intramolecular catalyzed hydrolysis reaction.

Three new kaempferol glycosides, kaempferol 3-O-β-D-glucopyranosyl-(16)-β-D-galactopyranosyl-7-O-α-L-rhamnopyranoside (1), kaempferol 3-O-β-D-galactopyranosyl-7-O-β-D-glucopyranosyl-(13)-α-L-rhamnopyranoside (2), and kaempferol 3-O-β-D-glucopyranosyl-(16)-β-D-galactopyranosyl-7-O-β-D-glucopyranosyl-(13)-α-L-rhamnopyranoside (3), were isolated from the whole herbs of Cardamine leucantha, along with three known kaempferol glycosides, kaempferol 7-O-α-L-rhamnopyranoside, kaempferitrin, and kaempferol 3-O-β-D-galactopyranosyl-7-O-α-L-rhamnopyranoside. Their structures were elucidated on the basis of spectroscopic methods.

Three unique phenylpropanoyl 2,7-anhydro-3-deoxy-2-octulosonic acid derivatives were isolated from Conyza canadensis (horseweed). Their structures were defined as rel-(1S,2R,3R,5S,7R)-methyl 7-caffeoyloxymethyl-2-hydroxy-3-feruloyloxy-6,8-dioxabicyclo[3.2.1]octane-5-carboxylate (1), rel-(1S,2R,3R,5S,7R)-methyl 7-feruloyloxymethyl-2-hydroxy-3-feruloyloxy-6,8-dioxabicyclo[3.2.1]octane-5-carboxylate (2), and rel-(1R,2R,3R,5S,7R)-methyl 7-feruloyloxymethyl-2-feruloyloxy-3-hydroxy-6,8-dioxabicyclo[3.2.1]octane-5-carboxylate (3). Compound 1 and a 5:3 mixture of compounds 2 and 3 were demonstrated to inhibit the catecholamine secretion induced by acetylcholine with IC(50) values of 94.65 and 42.35 microM, respectively, and to inhibit the catecholamine secretion induced by veratridine and high [K(+)] at a dose of 100 microM in cultured bovine adrenal medullary cells.

2-(2′-Oxo-3′-oximidocyclododecyl) cyclododecanone (1) and 2-(1′-hydroxylcyclododecyl) cyclododecanone (2) were synthesized and characterized. The conformation analysis was carried out based on the NMR, molecular mechanics calculation and X-ray diffraction. The conformation of two cyclododecyl moieties of both 1 and 2 was found to be the [3333]-2-one or [3333] square conformation both in the crystal state and the solution. The dihedral angle between carbonyl and the oxime double bond of the ring B is 180° in the crystal of 1. The protons or hydroxyl group of carbon atoms to link the two cyclododecyl moieties of 1 and 2 constitute dihedral angles of 174° in the crystal, and 175° in the solution, and the CC σ bond between two cyclododecyl moieties can not freely rotate in the solid state and the solution. In addition, compound 2 was the first example of α-corner-anti-monosubstituted cyclododecanone.

Roots of Hedysarum kirghisorum B. Fedtsch (Leguminosae, subfamily Papilionoideae) were collected at Tian-Shan mountain, Xinjiang Autonomous Region China, in July 2000 and were identified by Prof. Hu-Biao Chen, Department of Natural Medicines, Peking University. A voucher specimen (no. 99-w-001) was deposited at the Herbarium, School of Pharmaceutical Sciences, Peking University (PEM).

Two new saponins, named davuricoside L (1) and davuricoside O (2), have been isolated from the whole plants of Lysimachia davurica. Their structures were determined by 1D and 2D NMR, FAB-MS techniques, and chemical methods.

Pentacoordinated phosphoranes containing valine or iso-leucine residue (2-phenyl-2,75-spiro[1,3,2-phenanthrodioxaphosphole-2,2′-1,3,2-oxazaphospholan]-5′-one) were synthesized through sequential two-step reactions, whereby the reaction products of phenyldichlorophosphine with N,O-bis(trimethylsilyl)valine or iso-leucine were followed by the addition of phenanthrenequione, and the crystals of 4a and 4b were obtained from benzene and hexane mixed solution. The x-ray structure of the crystals 4a and 4b revealed that they are distorted TBP, exhibiting RP absolute configuration. The 31P NMR spectra showed that the SP diastereomer could transfer into the other one RP that came out from the solution during crystallization. Correspondingly, when it was dissolved in solvents the RP diastereomer transferred into the other one SP, and the pair of diastereomers changed each other in solution at room temperature through a phosphonium carboxylate zwitterions intermediate. The work was supported by the National Natural ...

Dinucleotide (TpAZT) phosphoramidates were synthesized through Atherton-Todd reaction of dinucleoside H-phosphonates and amino acid methyl esters, and their diastereomers (Rp and Sp) were separated by crystallization. It was showed that the cheap methyl esters of natural alanine and phenylalanine could act as new chiral auxiliaries for large-scale synthesis of dinucleotide analogs.

With (E/Z)-isomeric phytyl halides as side-chain materials, vitamin K 1 is synthesized via a Diels–Alder reaction to activate the free bridgehead hydrogen of 3 for the alkylation and a retro-Diels–Alder reaction to eliminate cyclopentadiene from 2 in a high yield, in which the configuration of the double bond in the phytyl side-chain is retained.

Novel aryl N-phosphonamidothionate derivatives of nucleosides as membrane-soluble prodrugs of bioactive free nucleotides have been prepared by phosphochloridothioate chemistry. Unprotected nucleosides, for example uridine and adenosine, were used; phosphorylation took place selectively at the 5′-position. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:62–66, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10080

Two new pterocarpenes were isolated from the roots of Hedysarum multijugum, and their structures were elucidated as hedysarimpterocarpene B (1) and hedysarimpterocarpene C (2) on the basis of spectroscopic data.

A stable penta-coordinated serine-carboxylic-phosphoric anhydride may be synthesized at temperatures below −18 °C. Above that temperature, the product was shown to isomerize to another penta-coordinated phosphorus compound, which was proven by the change in the magnitude of observed P–C coupling constants. The mechanism for the anhydride to ester isomerization might provide a clue to the proposal of high-energy supply for biochemistry. Organic bases were shown to exert little influence on the rate of isomerization.

Novel aryl thiophosphoramidate derivatives of the anti-HIV nucleoside analogue 3′-azido-3′-deoxythymidine (AZT) have been prepared by the thiophosphorochloridate chemistry. These materials were designed to act as membrane-soluble prodrugs of the bioactive free nucleotides.

Six new cycloartane triterpene glycosides (1-6), beesiosides A-F, were isolated from whole plants of Beesia calthaefolia, and their structures were elucidated on the basis of extensive NMR experiments and chemical methods. Beesiosides A-F were assigned as (20S,24R)-epoxy-9,19-cyclolanostane-3beta,16beta,18,25-tetraol-3-O-beta-D-xylopyranoside (1), (20S,24R)-epoxy-9,19-cyclolanostane-3beta,12beta,16beta,18,25-pentaol-3-O-beta-D-xylopyranoside (2), (20S,24R)-epoxy-9,19-cyclolanostane-3beta,12alpha,16beta,18,25-pentaol-3-O-beta-D-xylopyranoside (3), (20S,24R)-16beta-acetoxy-20,24-epoxy-9,19-cyclolanostane-3beta,12alpha,18,25-tetraol-3-O-beta-D-xylopyranoside (4), (20S,24R)-epoxy-9,19-cyclolanostane-3beta,15alpha,16beta,18,25-pentaol-3-O-beta-D-xylopyranoside (5), and (20S,24R)-16beta-acetoxy-20,24-epoxy-9,19-cyclolanostane-3beta,12beta,25-triol-3-O-beta-D-xylopyranoside (6), respectively.

A convenient, efficient and general method has been developed for synthesis of H-phosphonate mono and diesters of AZT and d4T through one-pot reaction of phosphonic acid with AZT or d4T and different alcohols using pivaloyl chloride as condensing agent under mild conditions.

A triterpenoid saponin (1) was obtained from the stem barks of Albizia julibrissin Durazz. Its structure was elucidated as 3-O-[beta-D-xylopyranosyl-(1 --2)-alpha-L-arabinopyranosyl-(1 --6)-beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O-beta-D-quinovopyranosyl-2, 7-octadienoyl]-16-deoxy-acacic acid 28-O-beta-D-glucopyranosyl-(1 --3)-[alpha-L-arabinofuranosyl-(1 --4)]-alpha-L-rhamnopyranosyl-(1 --2)-beta-D-glucopyranosyl ester (1), named as Julibroside J26, based on the chemical and spectral methods.

N,O-Bis(trimethylsilyl)-α-amino acids (N,O-BTMS-AA), mediated by o-phenylene phosphorochloridate (PPC), could oligomerize into polypeptides. The mechanism might go through sequential steps, i.e., t...

A new isomer of Julibroside J2 (Chen, S.P., Zhang, R.Y., Ma, L.B. and Tu, G.Z. Acta Pharm. Sinica, 1997, 32, 110–115) was obtained from the cytotoxic fraction of 95% ethanol extracts of stem barks of Albizia julibrissin Durazz, together with Julibroside J2. Its structure was elucidated as 3-O-[β-D-xylopyranosyl-(1 → 2)-α-L-arabinopyranosyl-(1 → 6)-β-D-glucopyranosyl]-21-O-{(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O-[3-O-((6S)-2-trans-2-hydroxymethyl-6-methyl-6-hydroxy-2,7 -octadienoyl)-β-D-quinovopyranosyl]-2,7-octadienoyl} acacic acid 28-O-β-D-glucopyranosyl-(1 → 3)-[α-L-arabinofuranosyl-(1 → 4)]-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranosyl ester(1), named as Julibroside J7, based on chemical and spectral methods. Julibroside J2 showed good inhibitory action against KB cell line in vitro.

Two new alkaloids named piperlactam S and piperine S have been isolated from the stem and leaves of Piper puberullum, in addition to puberullumine and three known pyridone alkaloids. The structures of these compounds were determined on the basis of spectral analyses. The known compounds were identified as piplartine dimer, piplartine and 8,9-dihydropiplartine and obtained for the first time from this species.

Five new 3-hydroxy-3-methylglutaryl (HMG) flavonol 3-O-glycosides, named oxytroflavosides A–E (1–5), and two new rhamnocitrin 3-O-glycosides, oxytroflavosides F and G (6 and 7) were isolated from the n-BuOH-soluble fraction of an EtOH extract of Oxytropis falcata together with seven known kaempferol glycosides (8–14), of which six were isolated from the genus Oxytropis for the first time. The structures of these compounds were elucidated by spectroscopic techniques and chemical methods. The absolute configuration of HMG in compounds 1–5 was determined to be S through spectroscopic analysis of the mevalonamide obtained by amidation and reduction of the HMG moiety. Compounds 1–10 were evaluated for anti-inflammatory activities using lipopolysaccharide-induced RAW 264.7 cells, but none of them showed inhibitory effects on NO production.

Two new triterpenoid saponins 1 and 2, along with six known saponins 3–8, were isolated from the roots of Dipsacus asper. The structures of new compounds were established as 3-O-β-d-glucopyranosyl-(1 → 4)-[α-l-rhamnopyranosyl-(1 → 3)]-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranosyl-hederagenin-28-O-β-d-glucopyranoside (dipsacus saponin J, 1) and 3-O-α-l-arabinopyranosyl-hederagenin-28-O-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranoside (dipsacus saponin K, 2). The structures were determined by extensive analysis of their spectroscopic data. Compounds 6 and 7 could significantly stimulate UMR106 cell proliferation and increase alkaline phosphatase activities in UMR106 cell at the concentration of 4 μM.

Two new alkaloids named piperlactam S and piperine S have been isolated from the stem and leaves of Piper puberullum, in addition to puberullumine and three known pyridone alkaloids. The structures of these compounds were determined on the basis of spectral analyses. The known compounds were identified as piplartine dimer, piplartine and 8,9-dihydropiplartine and obtained for the first time from this species.

Pentacoordinate spirobicyclic 2-phenoxy-1,3-phenylenedioxo-1,3,2-imino(alkyl)acetoxyphosphoranes are synthesized through a new and efficient method whereby phosphorus pentachloride is displaced stepwise by catechol, an N,O-bis(trimethylsilyl)amino acid and phenol (pathway A) or catechol, phenol and an N,O-bis(trimethylsilyl)amino acid (pathway B); this method has advantages of high yields, rapid reaction times and easy operation, which might provide a new route for the synthesis of other pentacoordinate phosphoranes.

A new natural red-purple azulene-type pigment, 1,1,6-trimethylazuleno[1,8-cd]pyran-3(1H)-one, named oreolactone (1), together with nine known compounds, scopoletin (2), pomolic acid (3), friedelin (4), 3β-friedelinol (5), 3α-friedelinol (6), stigmast-4-en-3-one (7), stigmast-4, 22-dien-3-one (8), β-sitosterol (9), and daucosterol (10), was isolated from the rhizomes of Oreocnide frutescens. The structures were elucidated on the basis of spectroscopic analysis.

Ofloxacin ((+/-)-9-fluoro-3-methyl-10-(4-methylpiperazin-1-yl)-7-oxo-2, 3-dihydro-7H-pyrido[1,2,3-de]-1, 4-benzoxazine-6-carboxylic acid) is a totally synthetic fluoroquinolone antimicrobial agent with a broad spectrum of activity against Gram-positive and Gram-negative bacteria and atypical pathogens such as Mycoplasma, Chlamydia and Legionella. Even though it is widely used for the treatment of gastrointestinal, pulmonary, urinary, and other infections, the comprehensive mechanism of action at molecular level has not been known so far. It is very important to understand the structural characteristics of the drug and the effects that are caused by the environments. With the purpose of deeply investigating the structure of Ofloxacin, an analog of Ofloxacin, Methyl-Ofloxacin (Me-OFL), was synthesized by methylation of 4'N in piperazine ring from Ofloxacin with CH3I. Then appropriate Me-OFL was dissolved in DC1/D2O and NaOH/D2O to prepare corresponding acidic and alkaline solutions. Systematic NMR spectroscopic investigation on Me-OFL in both acidic and alkaline solution was conducted using quantitative 1H and 13C spectra, DEPT, HSQC together with HMBC techniques. The spectra were recorded with Bruker AM-300 spectrometer and DRX500 spectrometer. Chemical shifts have been given in values referred to dioxane (deltaJ = 3.7, deltac = 67.8). Complete assignments on 1H and 13C signals of Me-OFL were obtained in different pH environments where the coupling constant between 13 C and 19F was found to be very helpful for the assignment of aromatic 13C signals. A comprehensive comparison between the 1H, 13C chemical shifts, together with the structural transformation in acidic and alkaline solutions was made and discussed in details. Due to the formation of hydrogen bond between COOH and C==O, the COOH and aromatic ring are in the same plane. As a result, a weak O...H--C hydrogen bond forms between C==O from the carboxyl group and 5-H from aromatic ring. In alkaline solution, the deprivation of H+ from COOH destroys not only the hydrogen bond between COOH and carbonyl group but also the weak hydrogen between the C==O from COOH and 5H. As a result, the 5H exhibited remarkable shift toward high field (1.02). Meanwhile, the chemical shift of 6C, 13C, 7C, 15C also exhibited remarkable shift to low field at 12. 04, 7.46, 4.33, 2.88 respectively. Such variations were related to the changes of p electrons from carboxyl group caused by the transformation between the carboxyl group and the carboxylate group in different pH environments. Comparison of deltaH, deltac data between Me-OFL and OFL in acidic solution and OFL in alkaline was made. In Me-OFL acidic solution, the chemical shift of 3'C, 5'C, 7'C, 8'C also exhibited remarkable shift to low field at 6.66-7.32 respectively, the chemical shift of 2'C and 6'C also exhibited remarkable shift to high field 6.04. In OFL acidic solution, the chemical shift of 2'C, 3'C, 5'C, 6'C, 7'C, 8'C also exhibited remarkable shift to high field within 2.39, Comparison between the protonation and the methylation on the 4'N atom from the piperazine ring was also made. The distribution of positive charge also showed difference. When protonation occurred on the piperazine ring, the positive charge was on the proton connected with 4'N. However, if methylation occurred, the positive charge is on the 4'-N atom.

From a China mangrove plant Acanthus ilicifolius Linn., a new compound, 5,11-epoxymegastigmane glucoside (1) was isolated along with one known compound of megastigmane glucosides, (6S, 9S)-roseoside (2). The structure of compound 1 was determined on the basis of 1D- and 2D-NMR techniques (DEPT, COSY, HMBC, HMQC, NOESY) and HR-FABMS. The structure of 1 was established as (1S, 3S, 5R, 6R, 7E)-5,11-epoxy-3-hydroxymegastigman-7-en-9-one-3-O-beta-D-glucopyranoside.

To study the constituents of the Prunella vulgaris L, the constituents were isolated by various column chromatography and the structures were identified on the basis of chemical and spectral analysis. One saponin compound (I) and one flavone glycoside compound (II) were obtained from Prunella vulgaris L. Their structures were elucidated as 16-oxo-17-demethyl-3beta,24-dihydroxylolean-12-en-3-O-beta-D-glucuronoside (I), and acacetin-7-O-beta-D-glucopyranoside (II). Compound I is a novel triterpenoid saponin and named as prunelloside A. Compound II was obtained for the first time from the Prunella genus.

Spatholobus sinensis is a plant of the Spatholobus genus (Leguminosae family). Its caulis are used as "ji-xue-teng" regionally. However, to our knowledge, no phytochemical investigation on S. sinensis has been reported to date. In this study, eight compounds were isolated from the ethanol extract of the caulis of S. sinensis, by solvents extraction and column chromatography methods. By analysis of their physic-chemical constants and spectral data, the structures of 8 compounds were identified as spatholosineside A (1), 2',4',5,7-tetrahydroxyisoflavone (2), isoliquiritigenin (3), lupinalbin A (4), coumestrol (5), naringenin (6), protocatechuic acid (7), leonuriside A (8). Compound 1 is a new compound.

Five new cyclolanostane triterpene glycosides, 12-deacetyloxy-15alpha-hydroxy-23-epi-26-deoxyactein, 12-deacetyloxy-23-epi-26-deoxyactein, 24-O-acetyldahurinol-3-O-beta-D-xylopyranoside, 12beta-hydroxycimigenol-3-O-beta-D-xylopyranosyl-(1--3)-beta-D-xylopyranoside, 25-anhydrocimicigenol-3-O-beta-D-(2'-O-acetyl)xylopyranoside, were isolated from the rhizome of Souliea vaginata collected in China. Their structures were elucidated by spectroscopic techniques, including 2D NMR spectra, and in the case of 5, by chemical correlation.

To in vestigate the constituents in root of Gentiana macrophylla.Various column chromatographic techniques were used for isolation and purification of the principles. The structures were elucidated on the basis of spectral data (UV, IR, MS, 1H-, 13C-NMR etc.) and identified by comparing with standard substance.Eight compounds were identified. Four compounds isolated from the chloroform fraction are: 5-carboxyl-3,4-dihydrogen-1H-2-benzopyran-1-one (1), erythrocentauric acid (2), roburic acid (3), oleanolic acid (4). Water fraction gave four known secoiridoid glucosides. They were: gentiopicroside (5), swertiamarine (6), sweroside (7), 6'-O-beta-D-glucosylgentiopicroside (8).1 is a novel compound. It was named as erythrocentauric acid. 2 was isolated from genus Gentiana and 8 was isolated from G. macrophylla for the first time.

To study the chemical constituents of the roots of Hedysarum multijugum Maxim.Compounds were isolated and purified by solvent and column chromatographic methods, and their structures were determined on the basis of physico-chemical properties and spectroscopic data.Seven compounds warangalone-4'-methyl ether (1), afrormosin (2), sissotrin (3) and ononin (4), naringenin-5, 7-di-O-beta-D-glucopyranoside (5), apigenin (6) and narcissin (7) were obtained from the roots of Hedysarum multijugum.Compound 1 is a new natural product, and other compounds; are obtained from the plant for the first time.

To study the lignan glycosides from the roots of Bupleurum scorzonerifolium. Chromatography methods was used to isolate compounds and chemical and spectral methods were used to identify the structures of isolated compounds.Two lignan glycosides were isolated from the roots of B. scorzonerifolium and their structures were identified as 2, 3-E-2,3-dihydro-2-(3'-methoxy-4'-O-beta-D-glucopyranosyl-phenyl)-3-hydroxymethyl-5-(3"-hydroxypropenyl )-7-methoxy-1-benzo [b] furan (1) and 2, 3-E-2, 3-dihydro-2-( 3'-methoxy-4'-hydroxy-phenyl)-3-hydroxymethyl-5-( 3"-hydroxypropenyl)-7-O-beta-D-glucopyranosyl-1-benzo[b]furan (2), both of them which were the mixture of (+)2S,3R- and (-)2R,3S-type diastereoisomer and in both of them the amount of (+)2S,3R-type was a little more than that of the (-)2R,3S-type.Compounds 1 and 2 were isolated from B. scorzonerifolium for the first time. (+)2S, 3R-2, 3-Dihydro-2-(3'-methoxy-4'-hydroxy-phenyl)-3-hydroxymethyl-5-(3"-hydroxypropenyl)-7-O-beta-D-glucopyranosyl-1-benzo[b] furan is a new compound.

To investigate the chemical constituents of Tibetan medicine Phyllanthus emblica.Various chromatographic techniques were employed for isolation and purification of the constituents, and the structures were elucidated by chemical and spectral analyses.11 compounds were isolated and identified as gallic acid (I), ellagic acid (II), 1-O-galloyl-beta-D-glucose (III), 3,6-di-O-galloyl-D-glucose (IV), chebulinic acid (V), quercetin (VI), chebulagic acid (VII), corilagin (VIII), 3-ethylgallic acid (3-ethoxy-4,5-dihydroxy-benzoic acid, IX), isostrictiniin (X), 1,6-di-O-galloyl-beta-D-glucose (XI).3-Ethylgallic acid (3-ethoxy-4,5-dihydroxy-benzoic acid) is a novel compound, and isostrictiniin was found from P. emblica for the first time.

Three new cycloartane triterpene glycosides, soulieosides A (1), B (2), and C (3), were isolated from the rhizomes of Souliea vaginata, and their structures were elucidated on the basis of extensive NMR experiments and chemical methods. Soulieosides A-C were assigned as 25-O-acetylcimigenol-3-O-beta-D-(2-acetyl)xylopyranoside (1), 24-O-acetyl-isodahurinol-3-O-beta-D-(2-acetyl)xylopyranoside (2) and 20(S),22(R),23(S),24(R)-16beta:23;22:25-diepoxy-3beta,23,24-trihydroxy-9,19-cyclolanostane-3-O-beta-D-(4-acetyl)xylopyranoside (3), respectively.

To investigate the chemical constituents of Phyllanthus urinaria L.Various chromatographic techniques were employed for the isolation and purification. The structure was elucidated by spectral analyses.A novel ellagitannin named phyllanthusiin G was isolated, its structure was established as 1-O-galloyl-2-phyllanthoyl-3,6-(R)-HHDP-beta-D-glucose.Phyllanthusiin G is a new compound.

Sequential transesterification of diphenyl phosphite with 5'-O-(4,4'-dimethoxytrityl)thymidine (1) and hydrogen sulfide gave O-[5'-O-(4,4'-dimethoxytrityl)thymidine-3'-yl] H-thiophosphonate (2), and subsequent condensation of 2 with AZT or d4T in the presence of diphenyl chlorophosphoate provided the dinucleotide H-thiophosphonates 3 or 3'. The Antherton-Todd reaction of 3 or 3' with L-amino acid methyl ester in a solution of CCl 4 -Et 3 N-H 2 O-MeCN gave the dinuleotide thiophosphoramidates 4 or 4', and removal of the dimethoxytrityl protecting group in formic acid yielded the target products AZT/d4T thiophosphoramidates 5 and 5'.

To seek for new bioactive constituents from the aerial parts of Cimicifuga dahurica.Various column chromatographic techniques were employed for the isolation and purification of the ingredients. The structures were elucidated on the basis of 1H, 13CNMR, 1H-1H COSY, HMQC, NOESY and HMBC spectra and chemical reactions.Two cyclolanostanol xylosides, cimidahuside C and D were isolated from the EtOAc section of EtOH extracts.Cimidahuside C(1) and D(2) are new triterpenoid xylosides.

With (E/Z)-isomeric phytyl halides as side-chain materials, vitamin K 1 is synthesized via a Diels–Alder reaction to activate the free bridgehead hydrogen of 3 for the alkylation and a retro-Diels–Alder reaction to eliminate cyclopentadiene from 2 in a high yield, in which the configuration of the double bond in the phytyl side-chain is retained.

Cimidahuside 1 and 2, two new cyclolanostanol xylosides were isolated from the aerial parts of Cimicifuga dahurica (Turcz.) MAXIM, on the basis of spectral data and chemical evidences, their structures were determined to be (20R,24R)-24,25-epoxy-3-beta-(beta-D-xylopyranosyloxy)-9,19-cyclolanost-7-ene-16,23-dione (1), and (20R,24R)-24,25-epxy-15-alpha-hydroxy-3-beta-((bet-D-xylpyranosyoxy)-9,19-cyclanost-7-ene-16,23-dione (2), respectively.

Novel aryl N-phosphonamidothionate derivatives of nucleosides as membrane-soluble prodrugs of bioactive free nucleotides have been prepared by phosphochloridothioate chemistry. Unprotected nucleosides, for example uridine and adenosine, were used; phosphorylation took place selectively at the 5′-position. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:62–66, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10080