Geometry,Electronic Structure,and Related Properties of Dye Sensitizer： 3,4-bis[1- （carboxymethyl）-3-indolyl]- 1 H-pyrrole-2,5-dione

The geometry, electronic structure, polarizability and hyperpolarizability of dye sensitizer 3,4-bis[1-（carboxymethyl）-3-indolyl]-1H-pyrrole-2,5-dione （BIMCOOH） were studied using density functional theory （DFT） with hybrid functional B3LYP, and the electronic absorption spectra were investigated using semi-empirical quantum chemical method ZINDO-1 and time-dependent DFT （TDDFT）. The results of natural bond orbital suggest that the natural charges of the dione, indole, and acetic groups are about 0.15e, -0.29e, and 0.44e, respectively. The calculated isotropic polarizability, polarizability anisotropy invariant and hyperpolarizability are 305.4, 188.3, and 1155.4 a.u., respectively. The electronic absorption spectral features in visible and near-UV region were assigned to the π→π^＊ transition due to the qualitative agreement between the experiment and the TDDFT calculations, and the transitions of the excited states 9-11 related to photoinduced intramolecular charge transfer processes. The analysis of electronic structure and UV-Vis absorption indicates that the indole groups primarily contributed sensitization of photo-to-currency conversion processes, and the interracial electron transfer between semiconductor TiO2 electrode and dye sensitizer BIMCOOH are electron injection processes from excited states of the dyes to the semiconductor conduction band.     

Asymmetric Synthesis of （R）- and （S）-Moprolol

A simple and effective procedure for the enantioselective synthesis of （R）- and （S）-moprolol was described. The key step was the asymmetric synthesis of enantiopure （R）- and （S）-guaifenesin, which were synthesized from enantioenriched （R）-3-chloro-l,2-propanediol and （S）-epichlorohydrin via kinetics of hydrolysis resolution of racemic epichlorohydrin by chiral Salen-Co^Ⅲ complex. The e.e. values of both the optical compounds were above 98%, and the chemical structures of the target compounds were confirmed by ^1H NMR, ^13C NMR, IR, and MS.     

Lipase immobilized on HOOC-MCF： A highly enantioselective catalyst for transesterification resolution of （R,S）-1-phenylethanol

Pseudomonas cepacia lipase (PSL) immobilized on the carboxyl-functionalized meso-cellular foams (HOOC-MCF) was used for the transesterification resolution of (R,S)-1-phenylethanol in organic solvent.The results showed that the ee value of (S)-1- phenylethanol and (R)-1-phenylethyl acetate reached 99% with 50% conversion of 1-phenylethanol using toluene as solvent. Furthermore,it was found that PSL/HOOC-MCF exhibited high enantioselectivity in organic solvent with log P≤2 such as toluene and hexane.     

Kinetic Resolution of 2-Chloro-1-（3,4-dichlorophenyl）ethanol by Lipase-Catalyzed Transesterification

Kinetic resolution of racemic 2-chloro-1-（3,4-dichlorophenyl）ethanol was performed by free Alcaligene sp. lipase-catalyzed irreversible transesterification affording the （R）-isomer with ≥95% ee and the （S）-isomer with ≥90% ee. The activity of lipase Alcaligene sp. strongly depends on the basicity of the reaction system, and an organic base such as triethylamine can enhance the activity of the lipase and enantioselectivity markedly.     

Determination of Pb（II） in environmental water by nano-ceria-graphene modified electrodeEI北大核心CSCD

Nafion solution as a binder,the Gr/CeO2 /Nafion/GCE modified electrode was prepared based on graphene （Gr）-nano cerium oxide （CeO2 ）composite materials. The electrochemical behavior of Pb（II）on the modified electrode was investigated using differential pulse anodic stripping voltammetry （DPASV）. Subsequently,a determination method for Pb（II）was established. The concentrations and ratio of composite materials,buffer solution pH,modification amount,enrichment potential and time were optimized. Under the optimal conditions ,the peak current of Gr/CeO2 /Nafion/GCE showed good linearity in the range of 0.24-48.31 μµmol/L of Pb（II）,and the detection limit was 4.3 nmol/L. Interference experiments showed that the other common anions and cations in water samples caused little interference to Pb（II）detection. Furthermore,the interference of Cu（II）within 10 times is acceptable. The modified electrode was used to the detection of Pb（II） in four complex water samples,and the recovery rates of the spiked assays were from 89.5% to 107.7%. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

（Salen）Ti（Ⅳ）-Catalyzed Asymmetric Ring-opening of meso Epoxides Using Dithiophosphorus Acid as the Nucleophile

The asymmetric ring-opening of epoxides with dithiophosphorus acids catalyzed by a （salen）Ti（Ⅳ） complex formed in situ from the reaction of Ti（OPr-i）4 and the chiral Schiff base derived from （1R,2R）-（＋）-diaminocyclohexane was realized. The resulting products were obtained with low to good enantioselectivity （up to 73% ee）.     

二茂铁衍生的手性硫膦配体在铱催化喹啉不对称氢化中的应用

 Chiral S,P-donor ferrocene-derived ligands were synthesized and applied in the asymmetric hydrogenation of quinolines using the ［Ir(COD)Cl］2/S,P-ligand complex as the catalyst in the presence of iodine. The effects of the solvent and hydrogen pressure on conversion and enantioselectivity were examined, and up to 82% ee was obtained. The planar chirality plays an important role in this reaction. R- and S-enantiomers of 1,2,3,4-tetrahydroquinoline derivatives were obtained using ligands 3 and 5, respectively.     

Silicon Effect on the Enantioselective Transcyanation of Acetyltrimethylsilane Examined by Different Oxynitrilases

The synthesis of optically active （R）- and （S）-2-trimethylsilyl-2-hydroxyl propionitrile by enantioselective transcyanation of acetyltrimethylsilane with acetone cyanohydrin was successfully carded out using defatted plum, loquat , peach, almond or apple seed meals as （R）-oxynitrilase source and using Manihot esculenta leaves as （S）-oxynitrilase source in a biphasic system with good conversion and high enantiomeric excess. Comparative study demonstrated that silicon atom in substrate showed great effect on the reaction and due to the unique characteristics of silicon atom, both the substrate conversion and the product e.e. of the transcyanation of acetyltrimethylsilane were much higher than those of its carbon counterpart 3,3-dimethyl-2-butanone for all examined oxynitrilases.     

Rapid detection of chlorpheniramine maleate by an electrochemical sensor based on metal-organic frameworks CHP@Cu3（BTC）2 /MWCNTsEI北大核心CSCD

Copper hydroxyphosphate@metal-organic frameworks/multi-wall carbon nanotube composites （CHP@Cu3 （BTC）2 /MWCNTs）were prepared by a new in-situ template method and then an electrochemical sensor was developed based on the composites. The crystal structure and morphology of the material were characterized by X-ray diffraction and scanning electron microscope. Cyclic voltammetry and linear sweep voltammetry were used to study the electrochemical catalytic performance，and the determination conditions were optimized. The rapid and sensitive detection of chlorphenamine maleate was realized. There was a good linear relationship between the oxidation peak current and concentration of chlorphenamine maleate in the ranges from 5 to 100 µμmol/L and from 150 to 800 µμmol/L，and the linear equations were as Ipa （µμA）=0.1559c（µμmol/L）-0.3533 （R2 =0.9973）and Ipa （µμA）=0.02328c（µμmol/L）+16.63（R2 =0.9594），and the detection limit was 1.67 µμmol/L. The recoveries of the actual drug ranged from 91.0% to 109.1%. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

Photochemical degradation of environmentally persistent perfluorooctanoic acid （PFOA） in the presence of Fe（Ⅲ）

Environmentally persistent and bioaccumulative perfluorooctanic acid （PFOA） was difficult to be decomposed under the irradiation of 254 nm UV light. However, in the presence of 80μmol/L Fe（Ⅲ）, 80% of PFOA with initial concentration of 48μmol/L （20 mg/L） was effectively degraded and 47.8% of fluorine atoms in PFOA molecule were transformed into inorganic fluoride ion after 4 h reaction. Shorter chain perfluorocarboxylic acids bearing C3-C7 and fluoride ion were detected and identified by LC/MS and IC as the degradation products in the aqueous solution. It was proposed that complexes of PFOA with Fe（Ⅲ） initiated degradation of PFOA irradiated with 254 nm UV light.     

From salmon pink to blue natural sensitizers for solar cells: Canna indica L., Salvia splendens, cowberry and Solanum nigrum L.

Study on dye-sensitized solar cells (DSSCs) with extracts of Canna indica L., Salvia splendens, Solanum nigrum L. as sensitizers is firstly reported in this paper. DSSCs were assembled by using natural dyes extracted from C. indica L., S. splendens, cowberry and S. nigrum L. as sensitizers. The energy conversion efficiency of the cells sensitized with dyes of C. indica L., S. splendens, cowberry and S. nigrum L. was 0.29%, 0.26%, 0.13% and 0.31%, respectively. A novel technique was taken to fabricate TiO₂ electrode films by electrophoresis. We present FTIR and UV–vis spectroscopy studies of structures and light absorption of these four kinds of natural dyes. The electrochemical impedance spectroscopy (EIS) was used to analyze the interface resistance of cells. The result indicated that high resistance existed in the interfaces of cell with cowberry extract as sensitizer.     

Antiviral activity of some Tunisian medicinal plants against Herpes simplex virus type 1

Fifteen species of Tunisian traditional medicinal plants, belonging to 10 families, were selected for this study. They were Inula viscosa (L.) Ait and Reichardia tingitana (L.) Roth ssp. discolor (Pom.) Batt. (Asteraceae), Mesembryanthemum cristallinum L. and M. nodiflorum L. (Aizoaceae), Arthrocnemum indicum (Willd.) Moq., Atriplex inflata Muell., A. parvifolia Lowe var. ifiniensis (Caball) Maire, and Salicornia fruticosa L. (Chenopodiaceae), Cistus monspeliensis L. (Cistaceae), Juniperus phoenicea L. (Cupressaceae), Erica multiflora L. (Ericaceae), Frankenia pulverulenta L. (Frankeniaceae), Hypericum crispum L. (Hypericaceae), Plantago coronopus L. ssp. eu-coronopus Pilger var. vulgaris G.G. (Plantaginaceae) and Zygophyllum album L. (Zygophyllaceae). Fifty extracts prepared from those plants were screened in order to assay their antiviral activity against Herpes simplex virus type 1 (HSV-1), using neutral red incorporation. Extracts from eight plants among these 15 showed some degree of antiviral activity, while the methanolic extract of E. multiflora was highly active with EC(50) of 132.6 microg mL(-1). These results corroborate that medicinal plants from Tunisia can be a rich source of potential antiviral compounds.     

An Improved On-Line HPLC-DPPH Method for the Screening of Free Radical Scavenging Compounds in Water Extracts of Lamiaceae Plants

An on-line HPLC-1,1-diphenyl-2-picrylhydrazyl (DPPH*) method has been improved for the detection of polar and nonpolar radical scavenging compounds from complex plant extracts. Eight water extracts were prepared from steam-distilled essential oil-extracted Lamiaceae plants (Origanum vulgare L., O. Onites L., O. Minutiflorum O. Schwartz et P. H. Davis, O. Syriacum L., Satureja cuneifolia Ten., Thymbra spicata L., Coridothymus capitatus (L.) Reichb. f., Majorana hortensis Moench). After the components within each extract had been separated by reverse phase chromatography using 10% to 100% methanol with 2% acetic acid as a mobile phase, analytes capable of scavenging a citric acid-sodium citrate buffered methanolic DPPH* solution were detected by post-column derivatization at 517 nm. The HPLC-DPPH* on-line method was applied to the qualitative and quantitative analysis of these Lamiaceae plant extracts. There was a strong correlation between the scavenging (negative) peak area and the concentration of the radical scavenging reference substances used. The radical scavenging compounds within the extracts were determined as benzoic acid and hydroxycinnamic acid derivatives, flavonoids and diterpenoids according to their retention time and UV spectral data. Rosmarinic acid and carnosic acid were identified as the dominant radical scavengers in these extracts by this method.     

自支撑CNTs/SMF-Ni电极上电催化氧气氧化茴香醚合成茴香醛

以具有三维开放网络结构的薄层大面积烧结8 μm金属纤维(SMF-Ni, SMF-SS(316L不锈钢))为基底, 通过乙烯催化化学气相沉积在金属纤维表面生长碳纳米管(CNTs)的方法, 制备了整体式CNTs/SMF-Ni (CNTs: 50% (w))和CNTs/SMF-SS (CNTs: 40% (w))复合材料. 研究表明, 以CNTs/SMF-Ni 为阴极材料、SMF-SS为阳极材料, 具有很高的直接电催化氧气氧化对甲氧基甲苯(茴香醚)合成对甲氧基苯甲醛(茴香醛) 的活性, 反应物转化率和产物选择性分别达95.4%和96.5%, 电流效率可超过80%.     

Triterpenoid contents and anti-inflammatory properties of the methanol extracts of ligustrum species leaves

Ligustrum (privet) plants are used by Chinese physicians to prevent and cure hepatitis and chronic bronchitis. Three common Ligustrum plant spp., namely Ligustrum lucidum Ait. (LL), L. pricei Hayata (LP) and L. sinensis Lour. (LS) were collected to assess their analgesic/anti-inflammatory properties on chemical-induced nociception and carrageenan-induced inflammation in rodents. The methanol extracts from Ligustrum plants leaves effectively inhibited nociceptive responses induced by 1% acetic acid and 1% formalin. LP and LL reduced the edema induced by 1% carrageenan. LP exhibited the best potency of the Ligustrum plants. Furthermore, LP reduced the abdominal Evan's blue extravasations caused by lipopolysaccharide, lipoteichoic acid, autocrines and sodium nitroprusside. The triterpenoid content of the three Ligustrum spp. was measured by high performance liquid chromatography using a photodiode array detector. LP contained the highest content of amyrin, betulinic acid and lupeol. LL had the highest content of oleanolic acid and ursolic acid. The various degrees of analgesic/anti-inflammatory effects among three Ligustrum plants may be related to their different triterpenoid contents. LP is a potential analgesic and anti-inflammatory Ligustrum plant. The effects of LP are partially related to the inhibition of cyclooxygenase-2 activity and a decrease in microvascular permeability via the actions of autocrines and kinins.     

Extraction of antioxidants from plants using ultrasonic methods and their antioxidant capacity

The analytical method based on the HPLC coupled with UV detection (HPLC‐UV) for the determination of selected antioxidants (i.e. esculetin, scopoletin, 7‐hydroxycoumarine, rutin, xanthotoxin, 5‐methoxypsoralen and quercetin) in plant material was developed. Two ultrasonic extraction methods for the isolation of these compounds from the plants such as Mentha longifolia L., Mentha spicata L., Ruta graveolens L., Achyllea millefolium L., Plantago lanceolata L. and Coriandrum sativum L. were used. Both of these methods, i.e. ultrasonic probe and ultrasonic bath, were optimised and compared to each other. For the proposed HPLC‐UV method LOQ values in the range from 22.7 (xanthotoxin) up to 97.2 ng/mL (rutin) were obtained. For all extracts the antioxidant capacity based on the reduction of free 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical was also determined. Obtained results ranged from 10.11 up to 73.50% of DPPH radical inhibition.     

Antiradical efficiency of 20 selected medicinal plants

The antioxidant system of a plant comprises a group of chemicals that are highly diverse in their sources, effects and uses. These antioxidants are capable of contracting and damaging free radicals. This investigation deals with a screening and comparison of the antioxidant activities of 20 selected medicinal plants and their parts, individually and in combination with vitamins A, C or E, using the DPPH radical scavenging method. Phyllanthus emblica L., Santalum album L., Syzygium cumini L. and Trigonella foenum-graecum L. presented highly significant antiradical efficiency (AE) singly and in combination with either vitamin A, C or E. Further, Curcuma longa L., Momordica charantia L., S. cumini, T. foenum-graecum, Moringa oleifera Lam and S. album have also shown fairly significant AE in a vitamin combination dose of 0.001 mM concentration.     

Terpenoids and related compounds from plants of the family Compositae (Asteraceae)

This review will summarize the authors' studies on the structures of terpenoids and related compounds from plants of the family Compositae (Asteraceae). Eighty three new compounds have been obtained and characterized from seven species of the plants, namely, Erigeron annuus (L.) Pers., Erigeron philadelphicus L., Erigeron sumatrensis Retz, Ligularia dentata Hara, Ligularia stenocephala Matsum. et Koidz., Petasites japonicus Maxim. and Tussilago farfara L.     

Anthocyans from Fruit of Some Plants of the Caprifoliaceae Family

The qualitative and quantitative compositions of anthocyans from fruit of plants of the Caprifoliaceae family grown under conditions of Belgorod region were investigated. The plants included elder species [Sambucus nigra L. (I), S. canadensis (II), and S. canadensis f. sceletoniana (III)], Viburnum opulus L., and Lonicera caerulea L. It has been found that the principal anthocyans of I are cyanidin-3-sambubioside (52.5%) and cyanidin-3-glucoside (37.1%) whereas from the other two elder species the principal component was cyanidin-3-sambubioside-5-glucoside, acylated p-coumaric acid, 70.9 (II) and 54.3% (III). Fruit of the other plants did not contain acylated anthocyans. The content of anthocyans in fresh or dried fruit was determined by spectrophotometry.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 132–133, March–April, 2005.     

Ethanol production from corn starch in a fluidized-bed bioreactor

The production of ethanol from industrial dry-milled corn starch was studied in a laboratory-scale fluidized-bed bioreactor using immobilized biocatalysts. Saccharification and fermentation were carried out either simultaneously or separately. Simultaneous saccharification and fermentation (SSF) experiments were performed using small, uniform κ-carrageenan beads (1.5–2.5 mm in diameter) of co-immobilized glucoamylase and Zymomonas mobilis. Dextrin feeds obtained by the hydrolysis of 15% drymilled corn starch were pumped through the bioreactor at residence times of 1.5–4h. Single-pass conversion of dextrins ranged from 54–89%, and ethanol concentrations of 23–36 g/L were obtained at volumetric productivities of 9–15 g/L-h. Very low levels of glucose were observed in the reactor, indicating that saccharification was the rate-limiting step. In separate hydrolysis and fermentation (SHF) experiments, dextrin feed solutions of 150–160 g/L were first pumped through an immobilized-glucoamylase packed column. At 55°C and a residence time of 1 h, greater than 95% conversion was obtained, giving product streams of 162–172 g glucose/L. These streams were then pumped through the fluidized-bed bioreactor containing immobilized Z. mobilis. At a residence time of 2 h, 94% conversion and ethanol concentration of 70 g/L were achieved, resulting in an overall process productivity of 23 g/L-h. Atresidence times of 1.5 and 1 h, conversions of 75 and 76%, ethanol concentrations of 49 and 47 g/L, and overall process productivities of 19 and 25 g/L-h, respectively, were achieved.