Three new phenolic glycosides from Curculigo orchioides G.

Three new phenolic glycosides, curculigosides F-H (1-3), were isolated from rhizomes of Curculigo orchioides Gaertn. Their structures were elucidated based on comprehensive spectroscopic analyses including IR, MS, 1D- and 2D NMR (HSQC, COSY, and HMBC). Curculigosides F-H (1-3) were evaluated for their anti-HBV activity in vitro using the HBV transfected Hep G2.

Polymorphic transformation of isotactic poly(1-butene) in form III upon heating: in situ synchrotron small- and wide-angle X-ray scattering studies.

The phase transformation of form III isotactic poly(1-butene) was investigated as a function of temperature. The polymer was isothermally precipitated from a dilute solution in iso-amyl acetate and observed with real-time synchrotron small- and wide-angle X-ray scattering techniques. The results confirmed that the polymorphic transition of form III was strongly dependent on temperature.

Four new trace phenolic glycosides from Curculigo orchioides.

Four new trace phenolic glycosides named orcinosides D (1), E (2), F (3), and G (4) were isolated from the rhizomes of Curculigo orchioides Gaertn. Based on comprehensive spectroscopic analyses including IR, FAB-MS, HR-ESI-MS, 1D- and 2D NMR (HSQC, HMBC), their structures were elucidated as orcinol-1-O-beta-D-xylopyranoside (1), orcinol-1-O-beta-D-apiofuranosyl-(1 --> 2)-beta-D-glucopyranoside (2), orcinol-3-O-beta-D-apiofuranosyl-1-O-beta-D-glucopyranoside (3), and 1-O-beta-D-glucopyranosyl-4-ethoxyl-3-hydroxymethylphenol (4).

[Chemical constituents from Piper longum].

Objective: To study the chemical constituents of Piper longum.

Method: The whole plant of air-dried P. longum was extracted with 95% EtOH.

Two new phenylpropanoid derivatives and other constituents from Illicium simonsii active against oral microbial organisms.

Bioassay-guided fractionation of the ethanol extract of the leaves and stems of Illicium simonsii led to the isolation of two new compounds, simonin A (1) and 1-hydroxyl-2- O- β- D-6'-acetyl-glucopyranosyl-4-allylbenzene (2), along with eight known compounds. Their structures were elucidated by spectroscopic analysis. The isolates were tested for anti-oral microbial activity using a microdilution method.

Two new compounds from the roots of Ligusticum chuanxiong.

Two new compounds, named ligusticoside A (1), a novel phthalide derivative with a lactone ring, and 4-pentylcyclohex-3-ene-1alpha,2beta-diol (2), were isolated from the rhizomes of Ligusticum chuanxiong. Their structures were determined by spectral methods (MS, IR, UV, 1D and 2D NMR). An X-ray diffraction experiment was performed to confirm the structure of compound 1.

Swerilactones C and D, anti-HBV new lactones from a traditional Chinese herb: Swertia mileensis.

Swerilactones C (1) and D (2), two novel diastereomeric lactones with an unprecedented 6/6/6/6/6 pentacyclic ring system, were isolated from the traditional Chinese herb Swertia mileensis. Their structures and relative stereochemistry were elucidated on the basis of spectroscopic methods and further confirmed by X-ray single-crystal diffraction analysis. In vitro antihepatitis B virus (HBV) assay on the Hep G 2.

Anti-HBV agents. Part 3: preliminary structure-activity relationships of tetra-acylalisol A derivatives as potent hepatitis B virus inhibitors.

Thirty-two tetra-acylated derivatives of alisol A were synthesized and evaluated for their anti-hepatitis B virus (HBV) activities and cytotoxicities in vitro. Among the series of alisol A derivatives examined, five analogues were active against HBV surface antigen (HBsAg) and HBV e antigen (HBeAg) secretion in HepG 2.2.

Microstructure and deformation behavior of polyethylene/montmorillonite nanocomposites with strong interfacial interaction.

Deformation behavior of polyethylene/modified montmorillonites with polymerizable surfactant (PE/P-MMT) nanocomposite with strong interfacial interaction was studied by means of morphology observation and X-ray scattering measurements. The orientation of PE chains was accompanied by the orientation of well-dispersed MMT platelets due to the presence of strong interfacial interaction, and both of the orientations were parallel to the deformation direction. The high degree of orientation of MMT platelets and PE chains resulted from the synergistic movement of PE matrix and MMTs, which originated from the presence of a network-like structure.

[Chemical constituents from air-dried Piper longum].

Objective: To study the chemical constituents of Piper longum.

Method: The whole plant of air-dried P. longum.

Swerilactones A and B, anti-HBV new lactones from a tradtional Chinese herb: Swertia mileensis as a treatment for viral hepatitis.

Swerilactones A (1) and B (2), two novel lactones with an unprecedented 6/6/6/6/6 pentacyclic ring system, were isolated from the traditional Chinese herb of Swertia mileensis with activity against the hepatitis virus. Their structures and relative stereochemistry were elucidated based on spectroscopic methods and further confirmed by X-ray single crystal diffraction analysis. In vitro antihepatitis B virus (HBV) assay on Hep G 2.

Henrylactones A-E and anti-HBV constituents from Illicium henryi.

Five new sesquiterpene lactones, henrylactones A-E ( 1- 5), together with ten known compounds: cycloparvifloralone ( 6), tashironin ( 7), tashironin A ( 8), neoanisatin ( 9), anisatin ( 10), anislactone B ( 11), 7- O-acetylanislactone B ( 12), merrillianolide ( 13), cyclomerrillianolide ( 14) and pseudomajucin ( 15), were isolated from the stems and roots of ILLICIUM HENRYI. Their structures were elucidated based on extensive spectroscopic data analyses. Among them, henrylactone A ( 1) is a novel sesquiterpene with a dilactone moiety and its structure was confirmed by X-ray diffraction.

Synthesis of a chiral quaternary carbon center bearing a fluorine atom: enantio- and diastereoselective guanidine-catalyzed addition of fluorocarbon nucleophiles.

The perfect combination: The title reaction provides adducts having quaternary carbon centers bearing a fluorine atom with high ee and d.r. values (see scheme).

Synthesis of alpha-stereogenic amides and ketones by enantioselective conjugate addition of 1,4-dicarbonyl but-2-enes.

In the conjugate addition reaction of a alpha,beta-unsaturated compound, the new stereogenic center is created in the beta-position. In contrast, conjugate addition to 1,4-dicarbonyl but-2-enes will generate an alpha-stereogenic center with respect to one of the carbonyl groups, which informally, can be considered as an inversion of normal reactivity patterns or Umpolung. In this paper, we demonstrate that chiral bicyclic guanidine can catalyze the addition of 1,3-dicarbonyl compounds to 1,4-dicarbonyl but-2-enes [(E)-4-oxo-4-arylbutenamides and (E)-4-oxo-4-arylbutenones] with high regioselectivity and enantioselectivity (ee values up to 97%).

Anti-HBV agents. Part 2: synthesis and in vitro anti-hepatitis B virus activities of alisol A derivatives.

Chemical modifications were performed on hydroxyl groups at C-11,23,24,25 positions and C-13(17) double bond of alisol A for structure-activity relationship study. Forty-one derivatives of alisol A were synthesized and assayed for their in vitro anti-hepatitis B virus (HBV) activities and cytotoxicities. Of them, 14 compounds were active against HBV surface antigen (HBsAg) and HBV e antigen (HBeAg) secretion in HepG 2.

[Chemical constituents from herbs of Swertia mileensis].

Objective: To study the chemical constituents of Swertia mileensis.

Method: The air-dried whole plants of S. mileensis were extracted with 50% EtOH.

[Five alkaloids from vine stems of Diploclisia affinis].

Objective: To study alkaloid constituents of Diploclisia affinis.

Method: The air-dried vine stems of D. affinis were extracted with 90% EtOH three times at room temperature.

Tandem conjugate addition-elimination reaction promoted by chiral pyrrolidinyl sulfonamide (CPS).

Chiral pyrrolidinyl sulfonamides have been found to promote the conjugate addition-elimination reaction between activated allylic bromides and 1,3-dicarbonyl compounds with high enantioselectivities and the highly functionalised products can be used to generate a variety of interesting enantiomerically pure compounds via simple transformations.

Two new dammarane triterpene glycosides from the rhizomes of Panax notoginseng.

Two new dammarane triterpene glycosides named notoginsenosides Rw 1 (1) and Rw 2 (2) were isolated from the rhizomes of Panax notoginseng, together with 20 known compounds including protopanaxadiol (3), protopanaxatriol (4), ginsenosides Rb1 (5), Rd (6), Re (7), Rg1 (8), Rg2 (9), 20-(S)-Rg3 (10), 20-(R)-Rg(3) (11), Rh1 (12), Rh4 (13), Rf (14), 20-O-glucopyranosyl Rf (15), notoginsenosides R1 (16), R2 (17), T5 (18), S (19), T (20), and Fa (21), and koryoginsenoside R1 (22). Based on FABMS, HRFABMS, IR, (1)H, 13C, and 2D-NMR (HSQC, HMBC, and COSY) spectral data, the structures of the new compounds were elucidated as 6-O-beta-d-xylopyranosyl-20-O-beta-d-xylopyranosyl-(1 --> 6)-beta-d-glucopyranosyldammar-24-ene-3beta,6alpha,12beta,20(S)tetraol (1) and 6-O-beta-d-xylopyranosyl-(1 --> 2)-beta-d-glucopyranosyldammar-22-ene-(trans)-3beta,6alpha,12beta,20(S), 25-pentaol (2). Compounds 3, 4, 13, and 22 were isolated from P.

Anti-HBV agents. Part 1: Synthesis of alisol A derivatives: a new class of hepatitis B virus inhibitors.

A series of alisol A derivatives were synthesized and evaluated for their anti-hepatitis B virus (HBV) activities and cytotoxicities in vitro. The preliminary investigation demonstrates that simple modifications of the parent structure of alisol A can produce a number of potentially important derivatives against HBV. The most active anti-HBV compound 6a showed high activities against the secretion of HBV surface antigen (IC(50)=0.

Dendrimer hydrazides as multivalent transient inter-cellular linkers.

Three-dimensional (3D) multi-cellular aggregates (MCAs), as a model scaffold-free tissue construct, are useful for engineering cell-dense and matrix-poor tissues for repair and regeneration applications. To facilitate rapid MCA formation with high degrees of linker consistency and performance, we synthesized a class of dendrimer hydrazides with 8, 16 and 32 arms that can react with the aldehyde on the modified cell surfaces to form MCAs. DAB-AM-16 hydrazide with 32 arms demonstrated the best cell aggregation ability as compared to the dendrimer hydrazides with fewer arms, facilitating MCA formation at lower linker concentrations, minimizing cytotoxicity.

Synthesis and in vitro anti-hepatitis B virus activities of 4-aryl-6-chloro-quinolin-2-one and 5-aryl-7-chloro-1,4-benzodiazepine derivatives.

A series of 4-aryl-6-chloro-quinolin-2-ones and 5-aryl-7-chloro-1,4-benzodiazepine were synthesized and assayed for their in vitro anti-hepatitis B virus activities and cytotoxicities for the first time. Some of the tested compounds were active against HBsAg and HBeAg secretion in Hep G2.2.

Periglaucines A-D, anti-HBV and -HIV-1 alkaloids from Pericampylus glaucus.

Four new hasubanane-type alkaloids, periglaucines A-D (1-4), and three known alkaloids, norruffscine (5), (-)-8-oxotetrahydropalmatine (6), and (-)-8-oxocanadine (7), were isolated from the aerial parts of Pericampylus glaucus. Their structures were elucidated on the basis of extensive NMR and EIMS data, and that of periglaucine A (1) was confirmed by single-crystal X-ray diffraction. Alkaloids 1-4 inhibited hepatitis B virus (HBV) surface antigen (HBsAg) secretion in Hep G2.

[Studies on chemical constituents from rhizomes of Panax notoginseng].

Objective: To study the chemical constituents from rhizomes of Panax notoginseng.

Methods: The constituents were isolated and purified by various chromatogragraphic methods, all compounds were identified on the basis of special analysis and physicochemical characters.

Results: Eight compounds were isolated from the 80% alcohol extract of the rhizomes and their structures were identified as ginsenoside Rh4 (I), ginsenoside Rh1 (II), ginsenoside Re (III), notoginsenoside R1 (IV) , ginsenoside Rd (V), ginsenoside Rh1 (VI), notoginsenoside S (VII), notoginsenoside T (VIII).