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The addition of formylphenylboronic acid derivatives to urea and ethyl acetoacetate proceeds in the absence of an additional Lewis acid catalyst to give the corresponding dihydropyrimidinones (Biginelli products) in good yields. Novel boron-containing dihydropyrimidinones have been investigated for their ability to act as anticancer agents against the breast cancer cell line MCF7. Key words: anticancer, Biginelli compounds, boronic acids, breast cancer, dihydropyrimidinones. L'addition de derives de l'acide formylphenylboronique sur l'uree et l'acetoacetate d'ethyle se produit, meme en l'absence d'un catalyseur acide de Lewis additionnel, pour conduire a la formation de dihydropyrimidinones (produits de Biginelli), avec de boris rendements. On a examine les proprietes antitumorales des nouvelles dihydropyrimidinones contenant du bore en faisant appel a des cellules de cancer du sein de la souche MCF7. Mots cles : antitumorale, composes de Biginelli, acides boroniques, cancer du sein, dihydropyrimidinones. [Traduit par la Redaction], Introduction Compounds containing boronic acids [[RB(OH).sub.2]] or boronate esters [[RB(OR').sub.2]] have found remarkable utility in Suzuki--Miyaura cross-coupling reactions (1) and as molecular recognition sensors (2). Interest in these compounds also [...]

Peptide and protein quantitation by liquid chromatography‐mass spectrometry relies on the assumption of linear signal response with concentration. At low concentrations, analyte adsorption to pipette tips, sample vials and equipment can have significant deleterious effects on signal response. Meanwhile at high concentrations, linearity breaks down due to competitive ionization, signal suppression, and the formation of peptide or protein multimers. These effects result in calibration curves that are more sigmoidal than linear. Linearity at low protein levels for identification and quantitation is of paramount importance in the discovery and validation of biomarker molecules. Herein, we demonstrate the benefits of using commercial low‐bind microcentrifuge tubes and LC vials on the response of a 27‐mer peptide, Vn96, and the intact proteins apomyoglobin and carbonic anhydrase. Linear curves were acquired for Vn96 while apomyoglobin required the addition of intact carbonic anhydrase as an adsorption competitor to achieve linearity. A linear calibration curve for carbonic anhydrase was also acquired by using the polypeptide ubiquitin as an adsorption competitor and internal standard. Linear response was recorded for approximately two orders of magnitude for apomyoglobin and carbonic anhydrase and three orders of magnitude for Vn96 with detection limits ranging from 0.33 to 19 fmol/µL. Finally, we used low‐bind vials for the online enzymatic digestion of apomyoglobin where a high concentration of apomyoglobin acted as an adsorption blocker for the low level trypsin enzyme. Fortunately, the liberated tryptic peptides showed no affinity for the walls of the low‐bind vials. In this study, we take a comprehensive approach to combat analyte adsorption by showing the significance of utilizing low‐bind vials and adsorption competitors to greatly improve upon signal sensitivity at low concentrations of target molecules. The use of these methodologies should improve the low‐level detection of molecules by mass spectrometry. [ABSTRACT FROM AUTHOR]

Abstract Background RNA-dependent gene silencing is becoming a routine tool used in laboratories worldwide. One of the important remaining hurdles in the selection of the target sequence, if not the most important one, is the designing of tools that have minimal off-target effects (i.e. cleaves only the desired sequence). Increasingly, in the current dawn of the post-genomic era, there is a heavy reliance on tools that are suitable for high-throughput functional genomics, consequently more and more bioinformatic software is becoming available. However, to date none have been designed to satisfy the ever-increasing need for the accurate selection of targets for a specific silencing reagent. Results In order to overcome this hurdle we have developed RiboSubstrates http://www.riboclub.org/ribosubstrates. This integrated bioinformatic software permits the searching of a cDNA database for all potential substrates for a given ribozyme. This includes the mRNAs that perfectly match the specific requirements of a given ribozyme, as well those including Wobble base pairs and mismatches. The results generated allow rapid selection of sequences suitable as targets for RNA degradation. The current web-based RiboSubstrates version permits the identification of potential gene targets for both SOFA-HDV ribozymes and for hammerhead ribozymes. Moreover, a minimal template for the search of siRNAs is also available. This flexible and reliable tool is easily adaptable for use with any RNA tool (i.e. other ribozymes, deoxyribozymes and antisense), and may use the information present in any cDNA bank. Conclusion RiboSubstrates should become an essential step for all, even including "non-RNA biologists", who endeavor to develop a gene-inactivation system.