Sodium Acetate-catalyzed Regiospecific and High Stereose- lective Aminobromination of β,β-Dicyanostyrene Derivatives with NBS as Nitrogen/Bromine Source

An easy and efficient method for the aminobromination of β,β-dicyanostyrene derivatives with NBS as the aminobrominating reagent in CH3CN catalyzed by NaOAc （10 mol%） is developed. This protocol provides con- venient process to convert β,β-dicyanostyrene derivatives into the vicinal haloamines with full regiospecificity and high stereoselectivety in the ice-water bath in air. The reaction is high efficient in yielding the corresponding ami- nobrominated products in excellent yields （up to 95%） under these conditions. The outcome indicated that the reac- tion has an electrophilic addition feature. 12 Eexamples of β,β-dicyanostyrene derivatives have been investigated.

Discovery and structure-activity relationship studies of novel tetrahydro-β-carboline derivatives as apoptosis initiators for treating bacterial infections

Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a new type of1,2,3,4-tetrahydro-β-carboline(THC)derivatives and evaluated the in vitro and in vivo bioactivities against the Xanthomonas oryzae pv.oryzae(Xoo),Xanthomonas axonopodis pv.citri(Xac),and Pseudomonas syringae pv.actinidiae(Psa).The in vitro bioassay results exhibited that most title molecules possessed good activity toward the three plant pathogenic bacteria,the compound A17 showed the most active against Xoo and Xac with EC50 values of 7.27 and 4.89 mg mL^(-1)respectively,and compound A8 exhibited the best inhibitory activity against Psa with EC50value of 4.87 mg mL^(-1).Pot experiments showed that compound A17 exhibited excellent in vivo antibacterial activities to manage rice bacterial leaf blight and citrus bacterial canker,with protective efficiencies of 52.67 and 79.79%at 200 mgmL^(-1),respectively.Meanwhile,compound A8 showed good control efficiency(84.31%)against kiwifruit bacterial canker at 200 mg mL^(-1).Antibacterial mechanism suggested that these compounds could interfere with the balance of the redox system,damage the cell membrane,and induce the apoptosis of Xoo cells.Taken together,our study revealed that tetrahydro-β-carboline derivatives could be a promising candidate model for novel broadspectrum bactericides.

High-Value-Added Utilization of Turpentine:Screening of Anti-Influenza Virus Agents fromβ-Pinene Derivatives

Turpentine is a renewable and resourceful forest product.The deep processing and utilization of turpentine,particularly its primary componentβ-pinene,has garnered widespread attention.This study aimed to synthesize 40 derivatives ofβ-pinene,including nopinone,3-cyanopyridines of nopinone,myrtanyl acid,myrtanyl acylthioureas,and myrtanyl amides.We assessed the antiviral activities of theseβ-pinene derivatives against influenza virus A/Puerto Rico/8/34(H1N1)using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method.Theβ-pinene derivatives were used before and after cellular infection with the influenza virus to evaluate their preventive and therapeutic effects against the H1N1 virus.The results showed that only compound 10o exhibited a preventive effect against the H1N1 virus with a half-maximal inhibitory concentration(IC50)value of 47.6μmol/L.Among the compounds,4e,4i,and 4l demonstrated therapeutic effects against cellular infection,with compound 4e displaying the most potent therapeutic effect(IC50=17.5μmol/L),comparable to the positive control ribavirin.These findings indicated that certainβ-pinene derivatives exhibited in vitro antiviral activity against the H1N1 influenza A virus,warranting further investigation as potential anti-influenza agents.

K3PO4-Catalyzed Regiospecific Bromoamidation of β, β-Dicyanostyrene Derivatives with N-Bromoacetamide（NBA）

An efficient method for the bromoamidation of β,β-dicyanostyrene derivatives with N-bromoacetamide （NBA） was developed.This protocol provides a convenient process to convert β,β-dicyanostyrene derivatives into the vicinal haloamines in excellent yields（up to 99％） at room temperature in the presence of anhydrous K3PO4 as a catalyst without the protection of the inert gaseous in CH2Cl2.A total of 11 examples were investigated and all the products showed the regionspecific feature.Based on the observation of different activities for the different substrates involving the electron-rich or electron-deficient β,β-dicyanostyrenes,a possible Michael addition mechanism was proposed.

Separation Properties of a New Polysiloxane-Anchored β-Cyclodextrin Derivative as Gas Chromatography Stationary Phase

A new capillary gas chromatography stationary phase, monokis (2,6 di O benzyl 3 O propyl (3’)) hexakis(2,6 di O benzyl 3 O methyl) β CD bonded polysiloxane, was synthesized. It exhibited separation abilities to disubstituted benzene isomers and some chiral solutes. It was also found that the polarity of CD derivatives can be lowered both by chemically bonding it to polysiloxane and by diluting it in polysiloxane. The separation abilities of the polysiloxane anchored CDs (SP CD) are higher than that of the unbonded CDs (S CD) and the diluted S CD at lower column temperature. Hydrosilylation reaction is one of the best methods to lower the operating temperature of CDs.

STRUCTURE,MOLECULAR WEIGHT AND BIOACTIVITIES OF(1→3)-β-D-GLUCANS AND ITS SULFATED DERIVATIVES FROM FOUR KINDS OF LENTINUS EDODES

Lentinan samples,(1→3)-β-D-glucans containing 4.6-15.2 wt% proteins,coded as L-I_1 L-I_2 L-I_3 and L-I_4(L-I)were isolated from four kinds of Lentinus edodes.These glucans were treated with acetone to remove the protein in orderto obtain free protein glucans coded as LNP-I_1,LNP-I_2.LNP-I_3 and LNP-I_4(LNP-I).The free-protein polysaccharideswere sulfated to give derivatives(S-LNP-I)with degree of substitution(DS)from 0.4-0.8.The structural features andweight-average molecular weight(M_w)of the samples were investigated by using infrared spectroscopy,elemental analysis,^(13)C-NMR,size exclusion chromatography combined with laser light scattering(SEC-LLS)and viscometry.The effects ofstructure and conformation of the polysaccharides on antitumor activities were assayed in vivo(Sarcoma 180 solid tumors)and in vitro(Sarcoma 180,HL-60,MCF-7 and Vero tumors).The results indicated that the predominant species of thesamples L-I and LNP-I in 0.2 mol/L NaCl aqueous solution existed as triple-helical chains with high rigidity and in dimethylsulfoxide(DMSO)as single-flexible chains.Interestingly,the antitumor activities of LNP-I are lower than those of the nativeglucans(L-I),whereas their sulfated derivatives have higher inhibition ratio against Sarcoma 180 than LNP-I.The resultsreveal that the binding of protein,sulfated modification and the triple helix conformation are important factors in theenhancement of the antitumor activities of polysaccharides on the whole.

Application of derivative ratio spectrophotometry for determination of β-carotene and astaxanthin from Phaffia rhodozyma extract

A derivative ratio spectrophotometric method was used for the simultaneous determination of β-carotene and astaxanthin produced from Phaffia rhodozyma. Absorbencies of a series of the standard carotenoids in the range of 441 nm to 490 nm demonstrated that their absorptive spectra accorded with Beer’s law and that the additivity when the concentrations of β-carotene and astaxanthin and their mixture were within the range of 0 to 5 μg/ml, 0 to 6 μg/ml, and 0 to 6 μg/ml, respectively. When the wavelength interval (?λ) at 2 nm was selected to calculate the first derivative ratio spectra values, the first derivative amplitudes at 461 nm and 466 nm were suitable for quantitatively determining β-carotene and astaxanthin, respectively. Effect of divisor on derivative ratio spectra could be neglected; any concentration used as divisor in range of 1.0 to 4.0 μg/ml is ideal for calculating the derivative ratio spectra values of the two carotenoids. Calibration graphs were established for β-carotene within 0?6.0 μg/ml and for astaxanthin within 0?5.0 μg/ml with their corresponding regressive equations in: y=?0.0082x?0.0002 and y=0.0146x?0.0006, respectively. R-square values in excess of 0.999 indicated the good linearity of the calibration graphs. Sample recovery rates were found satisfactory (>99%) with relative standard deviations (RSD) of less than 5%. This method was suc- cessfully applied to simultaneous determination of β-carotene and astaxanthin in the laboratory-prepared mixtures and the extract from the Phaffia rhodozyma culture.

Equilibrium Studies on Liquid-Liquid Reactive Extraction of Phenylsuccinic Acid Enantiomers Using Hydrophilicβ-CD Derivatives Extractants

This paper deals with the enantioseparation of phenylsuccinic acid(H2A)enantiomers by liquid-liquid reactive extraction usingβ-CD derivatives as aqueous selectors.Cyclodextrin and its derivatives can interact with guest molecules selectively to form complexes with different stabilities.Cyclodextrin derivatives are not soluble in organic liquids,but highly soluble in water.In this work,hydroxypropyl-β-cyclodextrin(HP-β-CD),hydroxyethyl- β-cyclodextrin(HE-β-CD)and methyl-β-cyclodextrin(Me-β-CD)were selected as chiral selectors in aqueous phase for the reactive extraction of phenylsuccinic acid enantiomers from organic phase to aqueous phase.The results show that the efficiency of the extraction depends,often strongly,on a number of process variables,including the types of organic solvents andβ-CD derivatives,the concentrations of the extractants and H2A enantiomers,pH and temperature.HP-β-CD,HE-β-CD and Me-β-CD have stronger recognition abilities for R-phenylsuccinic acid than for S-phenylsuccinic acid.Among the three kinds ofβ-CD derivatives,HP-β-CD has the strongest separation ability. Excellent enantioseparation was achieved under the optimal conditions of pH of 2.5 and temperature of 5°C with a maximum enantioselectivity(a)of 2.38.Reactive extraction of enantiomers with hydrophilicβ-CD derivatives is of strong chiral separation ability and can be hopeful for separations of various enantiomers at a large-scale.

Gas Chromatographic Enantiomer Separation of Cyclopropane Derivatives on Three 2, 6-Di-O-allyl-3-O-acylated-β- cyclodextrins Chiral Stationary Phases

Eight pairs of enantiomers of cyclopropane derivatives were resolved on capillary gas chromatographic columns using three new 2, 6-di-O-allyl-3-O-acylated-β-cyclodextrins as chiral stationary phases. It was found that the three β-CDs can separate some of the racemic cyclopropane derivatives well.

Inclusion Complexation of β-CD with Phenothiazine and N-Alkylphenothiazine Derivatives

Inclusion of Acyclodextrin (ACD) with phenothiazine 1 and Nalkylpheno-thiazine derivatives (alkyl = ethyl 2, isobutyl 3 and isopentyl 4) in aqueous solution was studied by means of UV-vis spectroscopy. The association constant Ka values for the inclusion of β-CD with 1, 2, 3 and 4 were determined to be 188, 214, 129 and 80 L/mol, respectively. It indicates that the stability of the inclusion complexes is dependent on the structure and the volume of the substituents in the guest compounds.

On quantitative structure-activity relationships between hydrazine derivatives and β irradiation

In this study, solutions of hydrazine and its derivatives were irradiated using a pulsed electron beam to determine the half-reaction time of radiolysis. 3 D structures of the hydrazine derivatives were optimized, and their energies were calculated using density functional theory with the B3 LYP method and 6-311 +(3 d, 3 p) basis set.For the first time, the 3 D quantitative structure-activity relationship(QSAR) equation describing the relationship between the hydrazine derivative structures and rate of radiolysis has been established using SPSS software.Pearson correlation analysis revealed a close correlation between the total energies of the molecules and half-reaction times. In the QSAR equation, Y =-7583.464 +54.687 X_1+94333.586 X_2,Y,X_1,and X_2 are the half-reaction time, total energy of the molecule, and orbital transition energy, respectively. The significance levels of the regression coefficients were 0.006 and 0.031, i.e., both less than 0.05. Thus, this model fully explains the relationship between hydrazine derivatives and β radiolysis stability.The results show that the total energy of the molecule and orbital transition energy are the main factors that influence the β radiolysis stability of these hydrazine derivatives.

One-pot Synthesis of α,β-Dehydroamino Derivatives from β,β-Dicyanostyrene with 1,3-Dibromo-5,5-dimethylhydantoin Promoted by Mild Base

The reaction of β,β-dicyanostyrene derivatives（l） with 1,3-dibromo-5,5-dimethylhydantoin（DBDMH） was systematicly studied. The reaction could generate different products when promoted by different mild bases. When the reaction was promoted by NaOAc（100%, molar ratio to compound 1）, β,β-dicyanostyrene derivatives could be directly converted into corresponding α,β-dehydroamino derivatives in good to excellent yields in one-pot. When the reaction was promoted by K3PO4（80%, molar ratio to compound 1）, the corresponding α,β-dehydroamino and double-α,β-dehydroamino compounds were simultaneously obtained and the total conversion of β,β-dicyanostyrene derivatives was up to 90% or higher.

SYNTHESIS AND CHARACTERIZATION OF NOVEL MULTIFUNCTIONAL HOST COMPOUNDS.1.β-CYCLODEXTRIN DERIVATIVE BEARING DIETHANOLAMINE MOIETY

A novel β-cyclodextrin(β-CD)derivative bearing diethanolamine moiety was synthesized by a convenient method with 63% yield,and the new host compound was characterized by (13)~C-NMR,FT-IR spectra etc,

Stereoselective Synthesis and Anticancer Activities of New Podophyllotoxin Derivatives:4-β-Cyano-4-Deoxy-4'-Demethylepipodophyllotoxin and 4-β-Carboxyl-4-Deoxy-4'-Demethylepipodophyllotoxin

4-β-Cyano-4-deoxy-4'-demethylepipodophyllotoxin 4 was synthesized from 4'-de -methylepipodophyllotoxin and Me3SiCN in the presence of BF3· Et2O. 4-β-Carboxyl-4-deoxy-4'-demethylepipodophyllotoxin 5 was obtained by hydrolyzing 4 in HOAc. Both of them show very high anticancer activities against L1210 and KB cell lines in vitro.

Octopus Manganese Porphyrin with Polyglycol Chains as a Catalyst for the β -Selective Epoxidation of Cholesterol Derivatives

Synthesis of a novel octopus porphyrin with polyglycol chains 1a was achieved. The catalytic activity of la's manganese complex for the epoxidation of cholesterol derivatives with PhIO give a satisfactory conversion and regioselectivity.

A Study on the Driving Force for Binding of Benzene Derivatives by α-and β-Cyclodextrin

A three-dimensional diagram shows that the association constants (Ka) for the inclusionof a- and 6-CD with substitUted benzene are mainly correIated with the molar refraction (R.) andhydrophobic constant (%) of the substitUents of guest compounds. It reveals that the inclusion ofcyclodextrin with the substitUted benzene is dondnantly driYen by van der Waals forces andhydrophobic interactions.

Determination Enantiomer Excess(e.e.%)of Chiral Sharpless Epoxides with β-Cyclodextrin Derivatives as Chiral Stationary Phases of Capillary Gas Chromatography

Using four β-cyclodextrin derivatives, 2,6-di-O-benzyl-3-O-heptanonyl-β-CD, 2,6-di- O-benzyl-3-O-octanonyl-β-CD, 2,3-di-O-benzyl-6-O-heptanonyl-β-CD, and 2,3-di-O-benzyl -6-O- octanonyl-β-CD, as chiral stationary phases of capillary gas chromatography （CGC）, the enantiomers of Sharpless epoxides were well separated. The enantiomer excess values （e.e.%） of some chiral Sharpless epoxides were also determined successfully using these CDs.

Selectivity of New β-Cyclodextrin Derivatives as CGC Stationary Phases and Application for the Analysis of Volatile Compounds in Traditional Chinese Medicines

New cyclodextrin derivatives （CDs）, heptakis（2, 6-di- O-methyl-3- O-methoxymethyl）-β-CD （ Ⅰ ） and heptakis（2, 3, 6-tri-O-methoxymethyl）-β-CD （ Ⅱ ）, were investigated for their chromatographic performance as stationary phases for capillary gas chromatography （CGC）. Both of the CDs exhibited good selectivity and satisfactory separation for test mixtures and aromatic positional isomers, and volatile compounds from Ligusticurn chuanxiong Hort. Additionally, the selectivity and elution orders of major compounds were compared with a well-recognized commercial column on the basis of the results by gas chromatography-mass spectrometry （GC-MS）. The present work demonstrates the good selectivity of the two new CDs and can be used as GC stationary phases for the separation of positional isomers and analytes in complex samples.

Preparation of Amide-Containing Insecticidal Derivatives from the Renewable Natural Productβ-Pinene

The preparation of bioactive derivatives from the renewable natural product pinene is a hot research topic in the deep processing and utilization of pinene.In this study,β-pinene was used to develop novel molecules as a promising new precursor of insecticide.A series of amide-containing derivatives ofβ-pinene were synthesized and characterized.The insecticidal activities of these derivatives against Mythimna separate and Semiaphis heraclei were tested.The structure characterization results showed that the characterization data of amide-containing derivatives were in full agreement with their proposed structures.The insecticidal activities evaluation results indicated that amide-containing derivatives exhibited weak insecticidal activity against Mythimna separate,but exhibited moderate to good insecticidal activity against Semiaphis heraclei.After testing for 72 h,the corrected mortality against Semiaphis heraclei of compounds 5c,5e,5f,5 h,5j,and 5 m was 100%at 1000 mg/L.The structure-activity relationship analysis results showed that the introduction of an amide group into the structure of derivatives improved their insecticidal activity against Semiaphis heraclei.Meanwhile,the amide-containing derivatives containing the F and NO_(2) substituted benzene ring might improve their insecticidal activity against Semiaphis heraclei.This study will be helpful for the high value-added utilization of the natural renewable resourceβ-pinene and the development of novel insecticides.

SYNTHESIS OF DERIVATIVES OF 3-β-D-XYLOPYRANOSYL-1,2,4-OXADIAZOLES

The synthesis of derivatives of 3-β-D-xylopyranosyl-1,2,4-oxadiazoles is accomplished by condensing protected β-D-xylopyranosyl amidoxime with acid anhydrides or various substituted benzoyl chlorides in good yield.The structures of now derivatives were identified by spectra and elemental analysis. The stability of 1,2,4-oxadiazole ring and mechanism of cyclization were. investigated.