One-pot three-component synthesis of 3-hydroxy-5,5-dimethyl-2-[phenyl(phenylthio)methyl]cyclohex-2-enone derivatives under ultrasound.

3-Hydroxy-5,5-dimethyl-2-[phenyl(phenylthio)methyl]cyclohex-2-enone is synthesized via one-pot three-component reactions of aromatic aldehyde, substituted thiophenol and 5,5-dimethyl-1,3-cyclohexanedione catalyzed by p-dodecylbenzene sulfonic acid (DBSA) under ultrasound. Under ultrasound irradiation the yields are much higher (sometimes substantially, by almost double) and the reaction time decreases substantially, the reaction conditions are milder. This method provides several advantages such as environment friendliness, high yields and simple work-up procedure and the protocol provides a novel alternative for the synthesis of thioether.

[Design, synthesis and activity of N-acyl-thiochromenothiazol-2-amine as acetylcholinesterase inhibitors].

A series of novel N-acyl-thiochromenothiazol-2-amine derivatives were designed and synthesized, furthermore, their inhibition effect on acetylcholinesterase was investigated. N-Acyl-thiochromenothiazol-2-amines were prepared from thiophenol by Hantzsch reaction, acylation reaction and substitution reaction. Moreover, their bioactivities as AChE inhibitors in vitro were measured with Ellman spectrophotometry. The results showed that most of them had a certain inhibition activity on AChE, and the compound 10a was the best in them. The IC50 of 10a to AChE is 7.92 µmol x L(-1), and the value is better than that of rivastigmine. N-Acyl-thiochromenothiazol-2-amine derivatives showed a certain bioactivity in vitro, which were worth further investigation.

[Design, synthesis and evaluation of N-acyl-4-phenylthiazole-2-amines as acetylcholinesterase inhibitors].

N-Acyl-4-phenylthiazole-2-amines were designed and synthesized, moreover their effects on acetylcholinesterase activities were tested. N-Acyl-4-phenylthiazole-2-amines were prepared from substituted 2-bromo-1-acetophenones by three steps reaction, and their AChE inhibitory activities were measured by Ellman method in vitro. The results showed that the target compounds had a certain inhibitory activity on AChE in vitro. Among them, 8c was the best, and IC50 of 8c was 0.51 micromol x L(-1), better than that of rivastigmine and Huperzine-A. The inhibitory activities of N-acyl-4-phenylthiazole-2-amines on acetylcholinesterase are worth while to be further studied.

[Design, synthesis and evaluation of new acetylcholinesterase inhibitors].

A series of novel 2-amino-4-phenylthiazole derivatives were designed and synthesized, furthermore, their inhibition effect on acetylcholinesterase were investigated. 2-Amino-4-phenylthiazoles were prepared from alpha-bromoacetophenones by Hantzsch reaction, acylation reaction and substitution reaction. Moreover, their bioactivities as AChE inhibitors in vitro were measured with Ellman spectrophotometry. The results showed that most of them had a certain inhibition activity on AChE, and the compound 8a was the best of them. The IC50 of 8a to AChE is 3.54 micromol x L(-1), and the value was better than that of rivastigmine. 2-Amino-4-phenylthiazole derivatives showed a certain bioactivity in vitro, which were worth further investigation.

Synergism and rules of the new combination drug Yiqijiedu formulae (YQJD) on ischemic stroke based on amino acids (AAs) metabolism.

The use of combination drugs is considered to be a promising strategy to control complex diseases such as ischemic stroke. The detection of metabolites has been used as a versatile tool to reveal the potential mechanism of diverse diseases. In this study, the levels of 12 endogenous AAs were simultaneously determined quantitatively in the MCAO rat brain using RRLC-QQQ method. Seven AAs were chosen as the potential biomarkers, and using PLS-DA analysis, the effects of the new combination drug YQJD, which is composed of ginsenosides, berberine, and jasminoidin, on those 7 AAs were evaluated. Four AAs, glutamic acid, homocysteine, methionine, and tryptophan, which changed significantly in the YQJD-treated groups compared to the vehicle groups (P < 0.05), were identified and designated as the AAs to use to further explore the synergism of YQJD. The result of a PCA showed that the combination of these three drugs exhibits the strongest synergistic effect compared to other combination groups and that ginsenosides might play a pivotal role, especially when combined with jasminoidin. We successfully explored the synergetic mechanism of multi-component and provided a new method for evaluating the integrated effects of combination drugs in the treatment of complex diseases.

Synthesis and pharmacological evaluation of novel bisindolylalkanes analogues.

In an effort to develop potent anti-cancer chemopreventive agents that act on topoisomerase II, a novel series of bisindolylalkanes analogues such as 3,3'-(thiochroman-4,4-diyl)bis(1H-indole) are synthesized. Structures of all compounds are elucidated by (1)H NMR, (13)C NMR and HRMS. Anti-proliferative activities for all of these compounds are investigated by the method of MTT assay on 7 human cancer lines. Most of them showed antitumor activities in vitro, the half maximal inhibitory concentration (IC50) value is 7.798 µg/mL of 3a against MCF7. Compound 3a showed comparable topoisomerase II inhibitory activity to etoposide (VP-16) at 100 µM concentration. The rest of the compounds also showed varying degree topoisomerase II inhibitory activity.

[Determination of endogenous amino acids in brain tissues after cerebral ischemia by RRLC-QQQ].

OBJECTIVE: To establish a method to determine underivatized endogenous amino acids in brain tissues after cerebral ischemia based on RRLC-QQQ. METHOD: Diamonsil chromatographic column C18 (4.6 mm x 250 mm, 5 microm) was adopted to determine 12 amino acids in 15 min, with acetonitrile-0.1% formic acid for gradient elution. The flow rate was set at 0.5 mL x min(-1). With ESI as the ion source, positive ion scanning mode was adopted for multi-reaction monitoring. RESULT: Each amino acid standard curve (AAs) showed good linear relationship within the detection range (r > 0.996), with the limit of detection of less than 11%, the limit of quantitation of less than 3.09 microg x L(-1). The RSD of intra- and inter-day precisions at high, middle and low concentrations were less than 11%. CONCLUSION: The determination results of actual samples showed that compared with the levels of AAs of the sham operation group, all of the remaining amino acids apart from N-acetyl-aspartate increased in brain tissues. Some amino acids showed significant changes in a time-dependent manner after the operation. The method is so simple, rapid and sensitive that it can be used for finding biological metabolite markers of cerebral ischemia, and exploring cerebral ischemia molecular mechanisms and synergistic mechanism of combined administration of multi-component traditional Chinese medicines.

An ion-pair principle for enantioseparations of basic analytes by nonaqueous capillary electrophoresis using the di-n-butyl L-tartrate-boric acid complex as chiral selector.

A chiral recognition mechanism of ion-pair principle has been proposed in this study. It rationalized the enantioseparations of some basic analytes using the complex of di-n-butyl l-tartrate and boric acid as the chiral selector in methanolic background electrolytes (BGEs) by nonaqueous capillary electrophoresis (NACE). An approach of mass spectrometer (MS) directly confirmed that triethylamine promoted the formation of negatively charged di-n-butyl l-tartrate-boric acid complex chiral counter ion with a complex ratio of 2:1. And the negatively charged counter ion was the real chiral selector in the ion-pair principle enantioseparations. It was assumed that triethylamine should play its role by adjusting the apparent acidity (pH*) of the running buffer to a higher value. Consequently, the effects of various basic electrolytes including inorganic and organic ones on the enantioseparations in NACE were investigated. The results showed that most of the basic electrolytes tested were favorable for the enantioseparations of basic analytes using di-n-butyl l-tartrate-boric acid complex as the chiral ion-pair selector.

[Advance of studies on metabolic fingerprinting analytical techniques and data processing methods].

Metabolomics is an emerging discipline subsequent to genomics, transcriptomics and proteomics, aiming for systematically studying the regularity of changes in metabolite to revealing organism's nature of movement and metabolism. It is especially important in modern pharmacological studies. Metabolic fingerprinting analysis is a method for metabolic analysis on high throughput of all metabolites, studying changes in drugs, organisms and endogenic metabolites caused by drugs and finding out related biomarkers to reflect dynamic changes inside organisms more directly and explain the mechanism of drugs and their effects on diseases. This essay summarizes some new metabolic fingerprint analytical methods and data processing methods used for metabolic fingerprint, elaborates their advantages and disadvantages and looks ahead to their combination with studies on traditional Chinese medicines, providing room for the development of new methods and new approaches for studies on complexity theory system of traditional Chinese medicines.

[Design, synthesis and in vitro antifungal activity of 3-substituted-methylenechroman-4-ones].

Substituted phenols as the starting materials were transformed into substituted chromanones by substitution reaction and cyclization reaction, and then 3-(hydroxymethylene)chroman-4-ones were synthesized from substituted chromanones by condensation reaction; at last, the target compounds were synthesized from 3-(hydroxymethylene)chroman-4-ones by chlorination reaction. Their structures were confirmed by 1H NMR and MS. The antifungal activity of the target compounds in vitro was measured by consecutive double dilution, and the result of antifungal experiment indicated that the target compounds had good antifungal action on most fungi tested in vitro. The MIC value of compounds 4c, 4e, 4g and 4h on M. gypseum is 1 microg x mL(-1), better than fluconazole and amphotericin B.

Ultrasound-assisted extraction of syringin from the bark of Ilex rotunda thumb using response surface methodology.

In this work, a rapid extraction method based on ultrasound-assisted extraction (UAE) of syringin from the bark of Ilex rotunda Thumb using response surface methodology (RSM) is described. The syringin was analyzed and quantified by high performance liquid chromatography coupled with UV detection (HPLC-UV). The extraction solvent, extraction temperature and extraction time, the three main factors for UAE, were optimized with Box-Behnken design (BBD) to obtain the highest extraction efficiency. The optimal conditions were the use of a sonication frequency of 40 kHz, 65% methanol as the solvent, an extraction time of 30 min and an extraction temperature of 40 °C. Using these optimal conditions, the experimental values agreed closely with the predicted values. The analysis of variance (ANOVA) indicated a high goodness of model fit and the success of the RSM method for optimizing syringin extraction from the bark of I. rotunda.

In situ synthesis of twelve dialkyltartrate-boric acid complexes and two polyols-boric acid complexes and their applications as chiral ion-pair selectors in nonaqueous capillary electrophoresis.

In this paper, twelve dialkyltartrate-boric acid complexes and two polyols-boric acid complexes were in situ synthesized by the reaction of different dialkyltartrates or polyols with boric acid in methanol containing triethylamine. All of the twelve dialkyltartrate-boric acid complexes were found to have relatively good chiral separation performance in nonaqueous capillary electrophoresis (NACE). Their chiral recognition effects in terms of both enantioselectivity (α) and resolution (R(s)) were similar when the number of carbon atoms was below six in the alkyl group of alcohol moiety. The dialkyltartrates containing alkyl groups of different structures but the same number of carbon atoms, i.e. one of straight chain and one of branched chain, also provided similar chiral recognition effects. Furthermore, it was demonstrated for the first time that two methanol insoluble polyols, D-mannitol and D-sorbitol, could react with boric acid to prepare chiral ion-pair selectors using methanol as the solvent medium.

Response surface modeling and optimization of accelerated solvent extraction of four lignans from fructus schisandrae.

A new method based on accelerated solvent extraction (ASE) combined with response surface methodology (RSM) modeling and optimization has been developed for the extraction of four lignans in Fructus Schisandrae (the fruits of Schisandra chinensis Baill). The RSM method, based on a three level and three variable Box-Behnken design (BBD), was employed to obtain the optimal combination of extraction condition. In brief, the lignans schizandrin, schisandrol B, deoxyschizandrin and schisandrin B were optimally extracted with 87% ethanol as extraction solvent, extraction temperature of 160 ° C, static extraction time of 10 min, extraction pressure of 1,500 psi, flush volume of 60% and one extraction cycle. The 3D response surface plot and the contour plot derived from the mathematical models were applied to determine the optimal conditions. Under the above conditions, the experimental value of four lignans was 14.72 mg/g, which is in close agreement with the value predicted by the model.

Hypoglycemic effect of protopanaxadiol-type ginsenosides and compound K on Type 2 diabetes mice induced by high-fat diet combining with streptozotocin via suppression of hepatic gluconeogenesis.

Compound K (CK) is a final intestinal metabolite of protopanaxadiol-type ginsenosides (PDG) from Panax ginseng. Although anti-diabetic activity of CK have been reported with genetic mouse models (db/db mice) in recent years, the therapeutic usefulness of CK and PDG in type 2 diabetes, a more prevalent form of diabetes, remains unclear. In the present investigation, we developed a mouse of non-insulin-dependent diabetes mellitus that closely simulated the metabolic abnormalities of the human disease. For this purpose, type 2 diabetes was induced in male ICR mice by combining of streptozotocin. The male ICR mice fed with HFD for 4 weeks received 100mg/kg of STZ injected intraperitoneally. After 4 weeks, mice with fasting (12h) blood glucose levels (FBG) above 7.8 mmol/L were divided into 3 groups (n=12) and treated with vehicle (diabetes model, DM), 300 mg/kg/day of PDG and 30 mg/kg/day of CK for 4 weeks while continuing on the high-fat diet. Hypoglycemic effects of CK and PDG were consistently demonstrated by FBG levels, and insulin-sensitizing effects were seen during oral glucose tolerance testing (OGTT). Moreover, the mechanism of hypoglycemic effect in type 2 diabetic mice was examined. Gluconeogenic genes, Phosphoenolpyruvate carboxykinase (PEPCK) and Glucose-6-phosphatase (G6Pase), were decreased in two treatment groups with CK showing greater effects. These findings demonstrated the hypoglycemic and insulin-sensitizing capabilities of CK on type 2 diabetes induced by HFD/STZ via down-regulation of PEPCK and G6Pase expression in liver.

The use of response surface methodology to optimize the ultrasound-assisted extraction of five anthraquinones from Rheum palmatum L.

In this paper, ultrasound-assisted extraction (UAE) was applied to the extraction of anthraquinones (aloe-emodin, rhein, emodin, chrysophanol and physcion) from Rheum palmatum L. The five anthraquinones were quantified and analyzed by high performance liquid chromatography coupled with UV detection (HPLC-UV). The extraction solvent, extraction temperature and extraction time parameters, the three main factors for UAE, were optimized with response surface methodology (RSM) to obtain the highest extraction efficiency. The optimal conditions were the use of 84% methanol as solvent, an extraction time of 33 min and an extraction temperature of 67°C. Under these optimal conditions, the experimental values agreed closely with the predicted values. The analysis of variance indicated a high goodness of model fit and the success of RSM method for optimizing anthraquinones extraction in Rheum palmatum L.

Di-n-amyl L-tartrate-boric acid complex chiral selector in situ synthesis and its application in chiral nonaqueous capillary electrophoresis.

A chiral selector, di-n-amyl L-tartrate-boric acid complex, was in situ synthesized by the reaction of di-n-amyl L-tartrate with boric acid in a nonaqueous background electrolyte (BGE) using methanol as the medium. And a new method of chiral nonaqueous capillary electrophoresis (NACE) was developed with the complex as the chiral selector. It has been demonstrated that the chiral selector is suitable for the enantioseparation of some ß-blockers and ß-agonists in NACE. Some chiral analytes that could not be resolved in aqueous microemulsion electrokinetic chromatography (MEEKC) with the same chiral selector obtained baseline resolutions in the NACE system. The enantioseparation mechanism was considered to be ion-pair principle and the nonaqueous system was more favorable for the ion-pair formation which is quite useful for the chiral recognition. The addition of a proper concentration of triethylamine into the BGE to control the apparent pH (pH*) enhanced the enantiomeric discrimination. In order to achieve a good enantioseparation, the effects of di-n-amyl L-tartrate and boric acid concentration, triethylamine concentration, applied voltage, as well as capillary length were investigated. Under the optimum conditions, all of the tested chiral analytes including six ß-blockers and five ß-agonists were baseline resolved.

[Fluorescence resonance energy transfer quenching method for determination of arsenic with acridine orange-rhodamine B].

A new method for the determination of trace arsenic was developed by using fluorescence resonance energy transfer from acridine orange (AO) to rhodamine B (RB). It was found that under the condition of lambda(ex)/lambda(em) = 470/580 nm, effective energy transfer could occur between AO and RB in the dodecyl benzene sodium sulfonate solution. The fluorescence intensity of RB was diminished by molybdoarsenide which was formed by the reaction of arsenic (V) with molybdate in sulfuric acid medium. The detection limit of this method was 2. 56 microg x L(-1). This method was used for the determination of trace arsenic in tea. The range of determination for arsenic was 0.01-0.25 mg x L(-1). The relative standard deviation for the determination of arsenic was 0.48%-0.64%. The recoveries for the addition of 0.01-0.03 mg x L(-1) arsenic were 98%-103%. The method has been applied to the determination of arsenic with satisfactory results.

[Determination of vitamin B12 concentration by fluorescence quenching with acridine orange-rhodamine 6G energy transfer system].

An energy transfer technique between acridine orange (AO) and rhodamine 6G (R6G) was studied, and the optimum experimental conditions of energy transfer were defined. It was found that the effective energy transfer could occur between AO and R6G in the dodecylbenzene sodium sulfonate solution with Na2 HPO4-citric acid buffer solution at pH 5.0. The fluorescence intensity of AO-R6G system was diminished by vitamin B12 in an alkalescence medium. Based on the AO-R6G energy transfer system anovel fluorescence quenching method for the determination of vitamin B12 has been developed. Under optimal conditious, the linear range of calibration curves for the determination of vitamin B12 was 0-3.0 x 10(-5) mol x L(-1). The detection limits were 4.8 x 10(-7) mol x L(-1) for Vitamin B12. Among six times of determination, the relative standard deviation was 0.51%-0.64%, and the recovery was 98.40% -103.62%. The method features good recurrence, rapidity of reaction, good stability, and few interfering substances. It can be satisfactorily used in the determination of the injection content of vitamin B12.

[Study on the enantiomer separation of cetirizine dihydrochloride using proteinate- and amylose-based chiral stationary phase].

AIM: To study the chromatographic behavior of cetirizine dihydrochloride on the proteinate- and amylose- based chiral stationary phases so as to optimizate the chromatographic condition of its enantiomers separation. METHODS: When using amylose-based, alpha1-acid glycoprotein and ovomucoid protein chiral stationary phase, the mobile phase was hexane-isopropyl alcohol-alcohol-trifluoroacetic acid (430:45:25:1), acetonitrile-10 mmol x L(-1) phosphate buffer solution (adjusted to pH 7.0 with sodium hydroxide) (4:96) and acetonitrile-20 mmol x L(-1) KH, PO4 solution (adjusted to pH 7.0 with triethylamine) (12.7:87.3), respectively. The temperature of proteinate column was 25 degrees C. The detective wavelength was 230 nm. RESULTS: The two enantiomers could be separated on the two kinds of chiral stationary phases without derivatization and the resolution was above 2.0. The methods developed on the two kinds of chiral stationary phases are accurate, sensitive and specific. CONCLUSION: Both the proteinate- and amylose-based chiral stationary phases can be used to separate the enantiomers of cetirizine.

[Chiral separation of enantiomers of synthesized amlodipine and its intermediate by capillary electrophoresis].

A capillary electrophoretic method for the chiral separation of enantiomers of synthesized amlodipine and its intermediate was developed. Several cyclodextrins (CDs) were applied as the chiral selectors and it was found that the ionic modified carboxymethyl-beta-cyclodextrin (CM-beta-CD) could give satisfactory enantioselectivity. In addition, the effects of the pH value of the buffer system, the concentration of the CD and the voltage on the chiral separation were investigated. The optimized buffer for amlodipine and its intermediate enantiomers was a buffer containing 30 mmol/L phosphate and 50 mmol/L CM-beta-CD (pH 6.12). Under these conditions, the resolutions of enantiomers of amlodipine and its intermediate were 1.73 and 1.55, respectively.