Small ligands interacting with the phosphotyrosine binding pocket of the Src SH2 protein

Unexpected Reaction of Dialkyl α-Hydroxy-benzylphosphonates with Dialkyl Phosphites and a Few Related Reactions

The condensation of dialkyl α-hydroxy-benzylphosphonates with dialkyl phosphites and that of α-hydroxybenzyl-diphenylphosphine oxide with diphenylphosphine oxide unexpectedly gave the corresponding phosphorylated α-hydroxy derivatives. This new reaction proved to be general. The formation of the two products may be similar and involves the attack of the hydroxy group of the α-hydroxyphosphonate or α-hydroxyphosphine oxide on the phosphorus atom of the trivalent tautomer form (Y2POH) of the Y2P(O)H reagent (Y= MeO, EtO, or Ph) going with the elimination of an alcohol and water molecule, respectively. The mechanism was supported by DFT computations at the M062X/6-31G (d,p) level of theory, including suitable proton transfer networks. The condensations discussed are typical autocatalytic reactions promoted by the alcohol or water molecules formed. The initial promoters are the traces of water inevitably present in the mixture. In the reaction of α-hydroxyphosphonates with dialkyl phosphites, the -P(O)(OR)H derivative is the primary product that is partially hydrolyzed to the -P(O)(OH)H species by the traces of water under the conditions of the reaction. Arbuzov reaction of diethyl α-bromobenzylphosphonate with ethyl diphenyphosphinite afforded the target-like phenylmethylene-phosphine oxide─phosphonate derivative.

Phosphonate Derivatives of Paracetamol and Valproic Acid

Paracetamol and valproic acid are standalone drugs with leading position in the world drug market. The phosphonate analogues of these drugs were synthesized and were tested in vivo. N-(4-hydroxyphenylcarbamoyl)phosphonic acid was four times more potent than paracetamol in preventing acetic acid-induced writhing. Phosphonate derivative of valproic acid, (2-propylpentanoyl)phosphonic acid, had similar in vivo activity to valproic acid in the pentylenetetrazole-induced kindling mouse model.

Identification and characterization of antibacterial compound(s) of cockroaches (Periplaneta americana)

Infectious diseases remain a significant threat to human health, contributing to more than 17 million deaths, annually. With the worsening trends of drug resistance, there is a need for newer and more powerful antimicrobial agents. We hypothesized that animals living in polluted environments are potential sources of antimicrobials. Under polluted milieus, organisms such as cockroaches encounter different types of microbes, including superbugs. Such creatures survive the onslaught of superbugs and are able to ward off disease by producing antimicrobial substances. Here, we characterized antibacterial properties in extracts of various body organs of cockroaches (Periplaneta americana) and showed potent antibacterial activity in crude brain extract against methicillin-resistant Staphylococcus aureus and neuropathogenic Escherichia coli K1. The size-exclusion spin columns revealed that the active compound(s) are less than 10 kDa in molecular mass. Using cytotoxicity assays, it was observed that pre-treatment of bacteria with lysates inhibited bacteria-mediated host cell cytotoxicity. Using spectra obtained with LC-MS on Agilent 1290 infinity liquid chromatograph, coupled with an Agilent 6460 triple quadruple mass spectrometer, tissues lysates were analysed. Among hundreds of compounds, only a few homologous compounds were identified that contained the isoquinoline group, chromene derivatives, thiazine groups, imidazoles, pyrrole-containing analogs, sulfonamides, furanones, and flavanones and known to possess broad-spectrum antimicrobial properties and anti-inflammatory, anti-tumour, and analgesic properties. Further identification, characterization, and functional studies using individual compounds can act as a breakthrough in developing novel therapeutics against various pathogens including superbugs.

A survey of the year 2002 commercial optical biosensor literature

We have compiled 819 articles published in the year 2002 that involved commercial optical biosensor technology. The literature demonstrates that the technology's application continues to increase as biosensors are contributing to diverse scientific fields and are used to examine interactions ranging in size from small molecules to whole cells. Also, the variety of available commercial biosensor platforms is increasing and the expertise of users is improving. In this review, we use the literature to focus on the basic types of biosensor experiments, including kinetics, equilibrium analysis, solution competition, active concentration determination and screening. In addition, using examples of particularly well-performed analyses, we illustrate the high information content available in the primary response data and emphasize the impact of including figures in publications to support the results of biosensor analyses.