A simple, sensitive and specific HPLC method was validated for the simultaneous determination of benzoic acid and sorbic acid in noodles. Sample preparation involved the extraction with methanol and water (60:40, v/v). The separation was achieved on a GerminiC18 modified silica column (50 mm x 4.6 mm i.d., 5 μm particle diameter). The mobile phase consisted of 0.05 M ammonium acetate (pH 4.4) a...

A number of Mycobacteria oxidize benzoic acid and some can use it as the sole source of carbon (1). Upon addition of benzoic acid to suspensions of washed organisms in the Warburg vessel its oxidation proceeds slowly for 30 to 60 minutes, then very rapidly until about half the amount of oxygen for complete combustion is taken up. The rate then parallels that of the autorespiration. It was thoug...

Substituent effects in N-H···O hydrogen bonds were estimated by comparing the acidities of two series of model compounds: N-benzoylanthranilic acids (A) and 4-benzoylamidobenzoic acids (B). Intramolecular N-H···O hydrogen bonds were found to be present in the A series of compounds, while B acids were used as control models. The respective pK(a) values for A and B acids were determined experimen...

In the presence of catalytic [{IrCp*Cl2 }2 ] and Ag2 CO3 , Li2 CO3 as the base, and acetone as the solvent, benzoic acids react with arenediazonium salts to give the corresponding diaryl-2-carboxylates under mild conditions. This C-H arylation process is generally applicable to diversely substituted substrates, ranging from extremely electron-rich to electron-poor derivatives. The carboxylate d...

Destabilization of the tetrameric fold of TTR (transthyretin) is important for aggregation of the protein which culminates in amyloid fibril formation. Many TTR mutations interfere with tetramer stability, increasing the amyloidogenic potential of the protein. The vast majority of proposed TTR fibrillogenesis inhibitors are based on in vitro assays with isolated protein, limiting their future u...

In this work was synthesized an amino-steroid derivative (4); the route involved preparation of dihydrotestosterone-hemisuccinate (2) by the esterification of dihydrotestosterone (1) using succinic anhydride and pyridine (method A) or using succinic acid and 1,3 dicyclohexylcarbodiimide in presence of p-toluensulfonic acid (method B). After 2 was coupled to 4-hidroxy benzoic acid using 1,3 dicy...

The chromogenic reagent described has been tested with seventy-nine indole derivatives and found to be very sensitive and indole-specific. The lower limit of detection on silica gel thin-layer plates was between 25 and 50 ng for most indoles. Phenols and hydroxy-, and amino-benzoic acids, hydroxy-, and methoxy-cinnamic acids did not yield chromophores with the exception of p-amino-benzoic acid ...

furin is a ca 2+ -dependent serine protease which cleaves proprotein substrates at the arg-xaa-(lys/arg)-arg    site to generate biologically active proteins. furin’s critical role in many cellular events associated with health disorders such as hiv, sars, anthrax, and influenza as well as cancer has made inhibitors of this enzyme as therapeutic targets. to this date, the most potent inhibitor ...

Infections related to Aspergillus species have emerged to become an important focus in infectious diseases, as a result of the increasing use of immunosuppressive agents and high fatality associated with invasive aspergillosis. However, laboratory diagnosis of Aspergillus infections remains difficult. In this study, by comparing the metabolomic profiles of the culture supernatants of 30 strains...

Five main compounds, including two iridoid glycosides (catalposide, verproside) and three phenolic compounds (luteolin, 4-hydroxy benzoic acid, 3,4-dihydroxy benzoic acid), were separated and prepared from the crude extract of Veronica ciliata by high-speed countercurrent chromatography. n-Hexane/n-butanol/water (1.5:5:5, v/v/v) was used for the separation of catalposide and verproside. n-Hexan...