Microwave promoted one-pot synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl)coumarins

A facile procedure for the synthesis of 3-（2′-amino-3′-cyano-4′-arylpyrid-6′-yl） coumarins are being reported starting from 3- acetylcoumarin, aromatic aldehydes and malononitrile. The reactions were carried out on microwave irradiation in good yield with short time and easy work-up. The structures of all the compounds have been confirmed on the basis of their analytical, IR, ^1H NMR, and mass spectral data.

A novel synthesis of 5-aryl-3-cyano-2-pyridones by using vinamidinium salts

A variety of vinamidinium salts were condensated with cyanoacetamide in refluxing methanol that contained sodium methoxide to produce 5-aryl-3-cyano-2-pyridones in good yield. Simple experimental conditions were used to prepare ten different 5-aryl-3- cyano-2-pyridones, four of which are new compounds.C 2009 Song Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

A cesium fluoride promoted efficient and rapid multicomponent synthesis of functionalized 2-amino-3-cyano-4H-pyran and spirooxindole derivatives

A rapid, one-pot and highly efficient protocol for the synthesis of pharmaceutically interesting functionalized 2-amino-3-cyano-4H-pyran and spirooxindole derivatives has been developed using commercially available Cs F as a catalyst in the reaction of malononitrile and aryl aldehydes or isatins with 1,3-cyclohexanediones. The major advantages of this methodology are excellent yield at ambient temperature, very short reaction time（5–10 min）, and use of an inexpensive catalyst.

Metabolic activity of Streptococcus mutans biofilms and gene expression during exposure to xylitol and sucrose

The objective of the study was to analyse Streptococcus mutans biofilms grown under different dietary conditions by using multifaceted methodological approaches to gain deeper insight into the cariogenic impact of carbohydrates. S. mutans biofilms were generated during a period of 24 h in the following media： Schaedler broth as a control medium containing endogenous glucose, Schaedler broth with an additional 5% sucrose, and Schaedler broth supplemented with 1% xylitol. The confocal laser scanning microscopy（CLSM）-based analyses of the microbial vitality, respiratory activity（5-cyano-2,3-ditolyl tetrazolium chloride, CTC） and production of extracellular polysaccharides（EPS） were performed separately in the inner, middle and outer biofilm layers. In addition to the microbiological sample testing, the glucose/sucrose consumption of the biofilm bacteria was quantified, and the expression of glucosyltransferases and other biofilm-associated genes was investigated. Xylitol exposure did not inhibit the viability of S. mutans biofilms, as monitored by the following experimental parameters： culture growth, vitality, CTC activity and EPS production. However,xylitol exposure caused a difference in gene expression compared to the control. Gtf C was upregulated only in the presence of xylitol.Under xylitol exposure, gtf B was upregulated by a factor of 6, while under sucrose exposure, it was upregulated by a factor of three.Compared with glucose and xylitol, sucrose increased cell vitality in all biofilm layers. In all nutrient media, the intrinsic glucose was almost completely consumed by the cells of the S. mutans biofilm within 24 h. After 24 h of biofilm formation, the multiparametric measurements showed that xylitol in the presence of glucose caused predominantly genotypic differences but did not induce metabolic differences compared to the control. Thus, the availability of dietary carbohydrates in either a pure or combined form seems to affect the cariogenic potential of S. mutans biofilms.

An environmentally friendly synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives catalyzed by tungstate sulfuric acid

An efficient three-component synthesis of 6-amino-4-aryl-5-cyano-3-metriyl-1-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles via a reaction between 3-methyl-1-phenyl-2-pyrazolin-5-one,aromatic aldehydes and malononitrile using tungstate sulfuric acid as a catalyst was described.Mild conditions,good to excellent yields,easily available catalyst and easy work-up are the key features of this method.

Synthesis of novel benzo[b]pyrimido[4',5':5,4]thieno[2,3-e][1,6]naphthyridine-8-ones via Pictet–Spengler cyclization

An efficient method for the synthesis of novel benzo[b]pyrimido[4′,5′：5,4]thieno[2,3e]-[1,6]naphthyridine-8-one derivatives via Pictet-Spengler cyclization is reported. The reaction of 4-（3-aminopyrimido[4,5-d]thieno-2-yl）quinoline-2-ones, which could be obtained from Thorpe-Ziegler isomerization of 4-bromomethylquinoline-2-ones and 5-cyano-1,6-dihydro-4-methyl-2-phenyl-6-thioxopyrimidine,with aromatic aldehydes in the presence of BF3·OEt2 gives pyrimidothieno[1,6]naphthyridines in good yields.

Reaction of Ketene Dithioacetals with Pyrazolylcarbohydrazide:Synthesis and Biological Activities of Ethyl 5-Amino-1-(5'- methyl-1'-t-butyl-4'-pyrazolyl)carbonyl-3-methylthio-1H-pyrazole-4-carboxylate

The title compound, C16H23N5O3S, ethyl 5-amino-1-(5'-methyl-1'-t-butyl-4'-pyrazolyl)carbonyl-3-methylthio- 1H-pyrazole-4-carboxylate (5) has been synthesized by the treatment of ethyl 2-cyano-3,3-dimethylthioacrylate with 1-t-butyl-5-methyl-4-hydrazinocarbonylpyrazole (4) in refluxed ethanol. The possible mechanism of the above reaction was also discussed. The results of biological test show that the title compound has fungicidal and plant growth regulation activities.

Synthesis of 5,6-Diarylpyridin-2（1H）-ones from Isoflavones

A simple method for the cyclocondensation of substituted isoflavones with cyanoacetamide in the presence of sodium hydroxide to give an array of 3-cyano-5,6-diarylpyridin-2（1H）-ones in good yields is reported.

Quantitative structure-retention relationship for photosystem Ⅱ inhibitors in RP-HPLC

Using factor analysis (principle component) and multiple linear regression methods,4 solute-related structure parameters were selected from 10 structure parameters and the relationships between the retention properties (logk’) of 25 2-cyano-3-methylthio-3-substituted amino-acrylates and the 4 parameters were established.There is a good agreement between the observed k’ values and the predicted fe’ values.