OBJECTIVETo study the chemical constituents in the stems of Kadsura oblongifolia.

METHODThe chemical constituents were isolated by various column chromatographic methods. The structures were identified by spectral data.

RESULTSeven compounds named kaempferol-3-O-alpha-L-arabinofuranoside (1), kaempferol-3-O-alpha-D-arabinopyranoside (2), quercetin-3-O-alpha-D-arabinopyranoside (3), quercetin-3-O-alpha- L-arabinofuranoside (4), quercetin-3-O-beta-D-glucopyranoside (5), quercetin (6), kaempferol (7) were isolated and identified.

CONCLUSIONCompounds 1-7 were obtained from this plant for the first time. Compounds 1-4 were isolated from Schisandraceae family for the first time.

Acetates ; chemistry ; Kadsura ; chemistry ; Plant Stems ; chemistry ; Solubility

OBJECTIVETo investigate the chemical constituents of Ehretia thyrsiflora.

METHODCompounds were isolated by using silica gel, Sephadex LH-20 and RP-C18 chromatography; their structures were elucidated by means of spectral data analysis.

RESULTSeven compounds were isolated and identified as methyl rosmarinate (1), caffeic acid (2), quercetin (3), kampferol (4), kaempferol 3-O-alpha-D-arabinoside (5), quercetin 3-O-alpha-D-arabinoside (6), and p-hydroxy benzoic acid (7).

CONCLUSIONAll these compounds were isolated from E. thyrsiflora for the first time. Compounds 2-7 were isolated from genus Ehretia for the first time.

Acetates ; analysis ; Boraginaceae ; chemistry ; Drugs, Chinese Herbal ; chemistry

Stereoselective transformation of Baylis-Hillman acetates 1 into corresponding (Z)-allyl iodides 2 has been achieved by treatment of 1 with samarium triiodide in THF. Remarkable rate acceleration of samarium triiodide-mediated iodination of 1 was found when ionic liquid 1-n-butyl-3-methyl-imidazolium tetrafluroborate ([bmim]BF(4)) was used as reaction media in stead of THF. This novel approach proceeds readily at 50 degrees C within a few minutes to afford (Z)-allyl iodides 2 in excellent yields. A mechanism involving stereoselective iodination of the acetates of Baylis-Hillman adducts by samarium triiodide is described, in which a six-membered ring transition state played a key role in the stereoselective formation of 2.
Acetates ; chemistry ; Iodides ; chemical synthesis ; Ions ; Kinetics ; Samarium ; chemistry ; Solutions

OBJECTIVETo study the chemical constituents of Sorbus tianschanica.

METHODThe compounds were isolated and purified by recrystallization and chromatography with silica gel and resin. Their structures were identified by physicochemical properties and spectral analysis.

RESULTSeven compounds were isolated from the EtOH extraction and six structures were identified as benzoic acid (1), benzyl-O-beta-D-glucopyranoside (2), ursolic acid (3), 2alpha-hydroxyursolic acid (4), hyperoside (5), quercetin-3-O-glucoside (6).

CONCLUSIONCompounds 1-5 were isolated from S. tianschanica for the first time.

Acetates ; chemistry ; Organic Chemicals ; analysis ; isolation & purification ; Sorbus ; chemistry

Eight compounds were isolated from the ethyl acetate extraction of Prunus mume by column chromatography. On the basis of physicochemical properties and spectrum analysis, these compounds were identified as isoquercitrin-6″-O-benzoate(1), pinoresinol(2), naringin(3), ethyl-β-D-glucopyranoside(4), astragalin(5), quercetin(6), hypericin(7), and rutin(8). Among them, compound 1 was a new natural product, and compounds 2-5 were isolated from this plant for the first time. In vitro study, compounds 1, 3, 5-8 could significantly increase the cell survival ratio.
Acetates ; Phytochemicals/analysis* ; Plant Extracts/chemistry* ; Prunus/chemistry* ; Solvents

Homoacetogens are a group of microorganisms with application potential to produce chemicals and biofuels by the bioconversion of synthesis gas. In this study, we collected waste activated sludge samples to screen homoacetogens by Hungate anaerobic technique, and studied the effect of pH on acetate and alcohol production from H2/CO2 gas. The mixed culture contained Clostridium ljungdahlii, Lysinibacillus fusiformis and Bacillus cereus. Acetate concentration achieved 31.69 mmol/L when the initial pH was 7. The mixed culture containing homoacetogen could converting H2/CO2 to acetate, which provides an efficient microbial resource for the bioconversion of synthesis gas.
Acetates ; chemistry ; Bacteria ; classification ; Biofuels ; Carbon Dioxide ; Hydrogen ; Sewage ; microbiology

Fourteen compounds were isolated and purified from the ethyl acetate of the ethanol extract of Shiaria bambusicola by various chromatographic methods, and their structures were elucidated by spectral techniques and physicochemical properties as hypocrellin A (1), hypocrellin B (2), hypocrellin C (3), hypomycin A (4), ergosterol (5), ergosterol peroxide (6), (22E, 24R)-5alpha, 8alpha-epidioxy-6,9(11),22-trien-3beta-ol (7), ergosta-7, 24(28)-dien-3beta-ol (8), (22E, 24R)-ergost-7, 22-dien-3beta, 5alpha, 6beta-triol (9), (22E,24R)-ergosta-7, 22-diene-3beta, 5alpha, 6beta-triol-3-O-palmitate (10), (22E, 24R)-ergosta-7, 22-diene-3beta, 5alpha, 6beta-triol-6-O-palmitate (11), 1-O-monostearin (12), 1, 3-O-distearin (13), and mannitol (14). Among them, compounds 7-13 were firstly isolated from this genus.
Acetates ; chemistry ; Ascomycota ; chemistry ; Biological Factors ; chemistry ; Molecular Structure ; Spectrometry, Mass, Electrospray Ionization

Poly lactic acid (PLA)/Poly (butyleneadipate-co-terephthalate)(PBAT) and glyceryl triacetate (GTA) blend were prepared by torque rheometer, and the effect of GTA on thermodynamical performance, mechanical properties and microstructure of PLA/PBAT composites were studied using differential scanning calorimeter(DSC), dynamic mechanical analysis(DMA), universal testing machine, impact testing machine and scanning electron microscope(SEM). After adding GTA, Tg values of the two phases gradually became closer, blends cold crystallization temperature and melting temperature decreased. When with 3 phr GTA, the dispersed phase particle size of PLA/PBAT blend decreased. Mechanics performance test showed that the elongation at break and impact strength of the PLA/PBAT blend was greatly increased with 3 phr GTA, and the elongation at break increased 2.6 times, improved from 17.7% to 64.1%.
Acetates ; chemistry ; Calorimetry, Differential Scanning ; Crystallization ; Lactic Acid ; Polyesters ; chemistry ; Polymers ; Temperature

OBJECTIVESince haloacetic acids (HAAs), which are nonvolatile and of high carcinogenic risk, are common species of chlorinated disinfection by-products(DBPs) in drinking water, and little has been known in China, it is necessary to make a survey about the kinds and levels of HAAs in drinking water of the nation.

METHODHAAs were analyzed using gas chromatography with electron capture detector(GC/ECD) and relatively complex pretreatment process of sample was applied. Five main cities in different areas of China were chosen in the survey.

RESULTSStudies showed that the main species of HAAs in drinking water in China were DCAA and TCAA, ranging from 0.4 microg/L to 12.85 microg/L and from 0.56 microg/L to 10.98 microg/L, respectively. MBAA and DBAA were also detected in one city, ranging from 2.20 microg/L to 4.95 microg/L and 1.10 microg/L to 2.81 microg/L, respectively. Therefore, the contents of HAAs varied, usually no more than 25 microg/L. Based on the acquired data to date, it is known that the concentrations of HAAs in drinking water in China were surely under the limits of Sanitary Standard for Drinking Water Quality (China, 2001).

CONCLUSIONA wider survey of HAAs in drinking water should be conducted throughout the nation to get adequate data and information, the ultimate aim of which is to control HAAs pollution and keep the balance between microbiological safety insurance and chemical risk control, minimize the formation of DBPs and ensure the safety of water supply at the same time.

Acetates ; analysis ; China ; Chlorine ; chemistry ; Cities ; Environmental Monitoring ; Halogens ; chemistry ; Humans ; Seasons ; Water Purification ; Water Supply

OBJECTIVETo determine ethylacetate and petroleum ether(60-90 ℃)in Haikesu 2,which is one of the raw materials of artificial musk,using the head-space gas chromatography.

METHODSThe determination was performed on HP-5(30 m×0.53 mm,5 Μm)capillary column with an hydrogen flame ionization detector. The solvent was dimethyl sulfoxide and the internal standard was methanol. The injector temperature and the detector temperature were controlled at 180 ℃ and 250 ℃,respectively. The carrier gas was nitrogen. The containers of head-space injector were preheated at 90 ℃ for 15 minutes. The column temperature was programmed raised,which achieved baseline separation of the components.

RESULTSThe results showed a good linear relationship for ethylacetate and petroleum ether(60-90 ℃)in their linearity range;and the limit of detection was 0.7 and 0.3 Μg/ml,respectively. The good precision and good average recoveries were satisfactory.

CONCLUSIONThe head-space gas chromatography is simple,rapid,and precise technique for the measurement of residual solvents in Haikesu 2.

Acetates ; analysis ; Chromatography, Gas ; Drugs, Chinese Herbal ; chemistry ; Fatty Acids, Monounsaturated ; chemistry ; Flame Ionization ; Solvents ; analysis