Arsenate removal from underground water by polystyrene-confined hydrated ferric oxide (HFO) nanoparticles:effect of humic acid.

Arsenic decontamination from groundwater is an urgent but still challenging task. Polystyrene-based hydrated ferric oxide (denoted as D201-HFO) nanocomposite is a new emerging current adsorbent for efficient arsenate removal in natural waters; the resulting materials can interact with arsenate, mainly driven by inner complexation and static interaction and the existing HA effects on adsorption was well investigated. Results reveals that low concentrations of HA (below 25 mg/L) coexistence led to negligible effects on As(V) removal, but high levels of HA (100 mg/L) exerted outstanding sorption competition to As(V) removal; kinetics results revealed the HA additions brought about the diffusion prolonging and capacity decline, due to the large molecule structure of HA.

[Flavonol glycosides from Lysimachia clethroides].

Eleven flavonol glycosides were isolated from the ethanol extract of Lysimachia clethroides by a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, and reversed-phase HPLC. Their structures were identified as astragalin (1), isoquercitrin (2), isorhamnetin-3-O-β-D-glucopyranoside (3), quercetin-3-O-β-D-6"-acetylglucopyranoside (4), quercetin-7-O-β-D-glucopyranoside (5), prunin (6), 2-hydroxynaringin-5-O-β-D-glucopyranoside (7), kaempferol-3-O-rutinonoside (8), kaempferol-3-O-robinobioside (9), rutin (10) and kaempferol-3,7-di-O-β-D-glucopyranoside (11). Among them, compounds 4, 7 and 11 were obtained from the Lysimachia genus for the first time, while compounds 3, 5 and 9 were firstly reported from this plant.

Three new norsesquiterpenoids from the seeds of Alpinia galanga.

From the seeds of Alpinia galanga Willd., three new norsesquiterpenoid racemic mixtures, galanols A-C (1-3) were isolated, along with three known sesquiterpenoids (4-6). Their structures were elucidated by means of UV, IR, HR-ESI-MS, 1D NMR and 2D NMR spectroscopic data.

The total synthesis of hypodematine.

Hypodematine, isolated from Hypodematium sinense Iwatsuki as an alkaloid with a new skeleton, was synthesized via nine reaction steps, in which the synthesis of 2-aryl-1-benzazocines via Beckmann rearrangement of 5H-benzocyclohepten-5-one oxime mesylate in dry toluene is discussed.

Bioactive carboxylic acids from Lysimachia clethroides.

Six new carboxylic acids (1-6), together with 11 known ones (7-17), were isolated from the aerial parts of Lysimachia clethroides. Their structures were elucidated on the basis of spectroscopic analysis and chemical evidence. Five new carboxylic acids (1 and 3-6) were evaluated for their in vitro inhibitory activity against aldose reductase.

Hepatoprotective iridoid glycosides from the roots of Rehmannia glutinosa.

Eleven new iridoid glycosides, rehmaglutosides A-K (1-11), together with 20 known analogues were isolated from the air-dried roots of Rehmannia glutinosa. The structures of these compounds were elucidated on the basis of spectroscopic data analysis and chemical evidence. Furthermore, in in vitro assays, compounds 3, 7, and 9-11 (10 μM) exhibited moderate hepatoprotective activities against D-galactosamine-induced HL-7702 cell damage.

Four new N-contained iridoid glycosides from flower buds of Lonicera japonica.

Four new N-contained iridoid glycosides, lonijapospiroside A (1), L-phenylalaninosecologanin B (2), L-phenylalaninosecologanin C (3), and dehydroprolinoylloganin A (4), were isolated from the flower buds of Lonicera japonica Thunb. Their structures were established on the basis of UV, IR, MS, and NMR spectral data.

Bioactive sesquiterpenoids from the rhizomes of Acorus calamus.

Eight new sesquiterpenes (1-8) and one new norsesquiterpene (9) named calamusins A-I were isolated from the ethanol extract of Acorus calamus rhizomes. The absolute configuration of compound 8 was determined by comparing its experimental and calculated ECD spectra. The absolute configurations of the other compounds were determined from their CD spectra.

Four new flavonoids from Morus australis.

Four new flavonoids, benzokuwanon E (1), hydroxymorusin (2), dicyclokuwanon EA (3), and dicyclokuwanon EB (4), were isolated from Morus australis. Their structures were elucidated on the basis of UV, IR, MS, NMR, and CD spectral data.

Steroidal alkaloids from the bulbs of Fritillaria unibracteata.

Two new steroidal alkaloids peimisine-3-O-β-D-glucopyranoside (1) and puqiedinone-3-O-β-D-glucopyranoside (3), together with three known compounds peimisine (2), puqiedinone (4), and puqiedine (5), were isolated and characterized from the bulbs of Fritillaria unibracteata. Their structures were fully elucidated by spectroscopic and chemical methods. Compound 1 showed moderate protection effect on neurotoxicity of PC12 cell lines induced by rotenone.

Cytotoxic triterpenoid saponins from Lysimachia clethroides.

Seven oleanane-type triterpenoid saponins, named clethroidosides A-G (1-7), an ursane-type triterpenoid saponin, clethroidoside H (8), and six known saponins were isolated from the aerial parts of Lysimachia clethroides. The structures of the saponins were elucidated on the basis of physical data analysis (1D and 2D NMR, HR-ESIMS) and chemical evidence. The cytotoxic activities of compounds 1-14 were evaluated against five human tumor cell lines (HT-29, HePG2, BGC-823, A549, and A375).

[Alkaloids and anthraquinones from branches and leaves of uvaria kurzii].

Objective: To investigate the chemical constituents of the branches and leaves of Uvaria kurzii.

Method: The compounds were isolated and purified by silica gel and Sephadex LH-20 column chromatographic methods. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data.

[Study on chemical constituents from branches and leaves of Polyalthia nemoralis].

Objective: To investigate the chemical constituents of the branches and leaves of Polyalthia nemoralis.

Method: The compounds were isolated and purified by silica gel, macroporous adsorption resin and Sephadex LH-20 column chromatographic methods. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data.

Chemical constituents of the stem bark of Morus cathayana.

Phytochemical investigation of the stem bark of Morus cathayana led to the isolation and identification of six new compounds, cathayanons F-J (1-5) and cathayanin A (6), and two known compounds, cathayanins B-C (7-8). Their structures were elucidated by spectroscopic methods. Compounds 1, 2, 3, 5, and 7 exhibited weak activities against five human cancer cell lines, with IC(50) values ranging from 4.

[Aporphine alkaloids from branches and leaves of Polyalthia nemoralis].

Objective: To investigate the aporphine alkaloids in the branches and leaves of Polyalthia nemoralis.

Method: The compounds were isolated and purified by silica gel and Sephadex LH-20 column chromatographies. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data.

Three new Diels-Alder type adducts from the stem bark of Morus cathayana.

Three new Diels-Alder type adducts cathayanons C (1), D (2), and E (3), together with one known compound sanggenon C (4), were isolated from the stem bark of Morus cathayana. Their structures were fully elucidated by spectroscopic and chemical methods. Compound 2 showed good anti-oxidation activity with the inhibitory rate of malondialdehyde being 88% at a concentration of 10(- 6) mol/l.

2-Arylbenzofuran Derivatives from Morus cathayana.

Four new 2-arylbenzofuran derivatives, cathafurans A (1), B (2), C (3), and D (4), were isolated from the stem bark of Morus cathayana. Their structures were determined by spectroscopic methods. Compounds 2 and 3 exhibited moderate activities against five human cancer cell lines, with IC(50) values ranging from 6.

The synthesis of analogs of shuangkangsu, a novel natural cycloperoxide glucoside from Lonicera japonica Thunb.

Four novel optically pure cycloperoxide glucosides 9a, 9b, 10a, and 10b, analogs of shuangkangsu--a natural product with unusual skeleton and antivirus activity from the buds of Lonicera japonica Thunb, were firstly synthesized by employing peroxidation and glucosidation reactions from phthalaldehyde or 4,5-dichloro phthalaldehyde and glucose.

Two new dimeric stilbenes from the stem bark of Morus australis.

Two new dimeric stilbenes austrafuran B and austrafuran C were isolated from the bark of Morus australis. Their structures were elucidated on the basis of spectroscopic methods.

Sorption enhancement of 1-naphthol onto a hydrophilic hyper-cross-linked polymer resin.

A hydrophilic hyper-cross-linked polymer resin NDA-150 was developed to remove 1-naphthol from the contaminated waters. The sorption performance of 1-naphthol on NDA-150 was explored and compared with that on the commercial hydrophobic resin XAD-4. The sorption rates of 1-naphthol onto both of the two resins obey the pseudo-second-order kinetics, and are limited by the successive steps of film diffusion and intraparticle diffusion.

Four new alkaloids from Polyalthia nemoralis (Annonaceae).

Four new alkaloids, polynemoralines A (1), B (2), C (3), and D (4), were isolated from the branches and leaves of Polyalthia nemoralis A DC. The structures of 1-4 were elucidated mainly on the basis of spectroscopic methods. The structure of 4 was confirmed by X-ray diffraction analysis.

Equilibrium and heat of adsorption of diethyl phthalate on heterogeneous adsorbents.

Removal of phthalate esters from water has been of considerable concern recently. In the present study, the adsorptive removal performance of diethyl phthalate (DEP) from water was investigated with the aminated polystyrene resin (NDA-101) and oxidized polystyrene resin (NDA-702). In addition, the commercial homogeneous polystyrene resin (XAD-4) and acrylic ester resin (Amberlite XAD-7) as well as coal-based granular activated carbon (AC-750) were chosen for comparison.

Removal enhancement of 1-naphthol and 1-naphthylamine in single and binary aqueous phase by acid-basic interactions with polymer adsorbents.

In the present study removal performance of 1-naphthol and 1-naphthylamine from wastewater by single and binary adsorption was compared. Synergistic effects were investigated in single-solute, binary-solute, and the preloading adsorption systems at 293 K. Two commercial polystyrene adsorbents Amberlite XAD-4, a macroporous adsorbent, and NDA-100, a hyper-cross-linked adsorbent, were employed here for their frequent use in organic pollutants removal from contaminated waters.

Application of the Polanyi potential theory to phthalates adsorption from aqueous solution with hyper-cross-linked polymer resins.

The adsorption equilibria of dimethyl phthalate (DMP) and diethyl phthalate (DEP) on two hyper-cross-linked polymer resins (NDA-99 and NDA-150) in aqueous solution were investigated at 298 K. And a coal-based granular activated carbon (AC-750) was chosen for comparison. All the adsorption equilibrium data of DMP were well fitted by the Polanyi-based isotherm modeling (Polanyi-Manes (PM) equation), and the characteristic curves of the three adsorbents were obtained.

Evaluation of enantiopure N-(ferrocenylmethyl)azetidin-2-yl(diphenyl)methanol for catalytic asymmetric addition of organozinc reagents to aldehydes.

A facile and practical approach to preparation of enantiopure N-(ferrocenylmethyl)azetidin-2-yl(diphenyl)methanol was developed from cheap and easily available l-(+)-methionine. Synthetic highlights include the three-step, one-pot construction of the chiral azetidine ring and the development of an improved one-step procedure for the synthesis of the key intermediate l-2-amino-4-bromobutanoic acid. Enantiopure N-(ferrocenylmethyl)azetidin-2-yl(diphenyl)methanol was evaluated for catalytic asymmetric addition of organozinc reagents to aldehydes.