Stability studies of endocrine disrupting tributyltin and triphenyltin compounds in an artificial sea water model.

Triorganotins belong to toxic components present predominantly in antifouling paints for marine vessels. Tributyltin/triphenyltin at pico- or nanomolar concentrations in sea water are known to induce an irreversible sexual abnormality in females of over 190 marine species, an "imposex" phenomenon - the superimposition of male genitalia on a female. Moreover, trialkyltins and triaryltins function as potent nuclear retinoid X receptors (RXR) agonists.

Synthesis and antibacterial activities of N-substituted-glycinyl 1H-1,2,3-triazolyl oxazolidinones.

A series of 1H-1,2,3-triazolyl piperazino oxazolidinone analogs with optionally varied glycinyl substitutions were synthesized and their antibacterial activity assessed against a panel of susceptible and resistant Gram-positive and selected Gram-negative bacteria including clinical isolates. The N-aroyl- and N-heteroaroyl-glycinyl (MIC: 0.06-4 μg/ml) derivatives were more potent than the N-acylglycinyl (2-8 μg/ml) derivatives against all Gram-positive bacteria tested.

Effects of varied substituents on the antibacterial activity of triazolylmethyl oxazolidinones.

A number of 1,2,3-triazolylmethyl piperazino oxazolidinone derivatives with optionally varied substituents at the 4N-piperazine position were synthesized and their antibacterial activity evaluated against a panel of susceptible and resistant Gram-positive and selected Gram-negative bacteria. Substitution with 5-membered heteroaroyl and dinitrobenzoyl moieties potentiated activity against staphylococci and enterococci strains. Furthermore, the compounds having dinitrobenzoyl 7n, 7o, and 5-nitrofuroyl 7t substitutions were four- to eightfold more potent than linezolid against M.

Assessment of the stability of novel antibacterial triazolyl oxazolidinones using a stability-indicating high-performance liquid chromatography method.

Objectives: To evaluate the stability of 12 triazolyl oxazolidinone (TOZ) derivatives in simulated gastric and intestinal fluids as well as in human plasma at 37 ± 1°C.

Materials And Methods: A stability-indicating high-performance liquid chromatography (HPLC) procedure with a C(8) column (250 × 40 mm, 5 μm particle size) and a mobile phase of acetonitrile/H(2)O (50/50 v/v) at 1.0 ml/min was used.

Synthesis and antibacterial activity of novel 5-(4-methyl-1H-1,2,3-triazole) methyl oxazolidinones.

A series of 5-(4-methyl-1,2,3-triazole)methyl oxazolidinones were synthesized and tested for their antibacterial activity against a panel of Gram-positive and Gram-negative clinical isolates in comparison with linezolid and vancomycin. Most of the compounds demonstrated strong to moderate in vitro antibacterial activity against susceptible and resistant Gram-positive pathogenic bacteria. Antibacterial activity varied with substitutions at the phenyl C4 position with bulky alkylcarbonyl and alkoxycarbonyl substitutions on the piperazine N4 being detrimental to antibacterial activity.

Determination of novel antibacterial triazolylmethyl oxazolidinones concentrations in human plasma by APCI-LC-MS: application to stability study.

Unlabelled: Triazolylmethyl oxazolidinones are novel potent antibacterial agents recently synthesized in our laboratory.

Purpose: Development of a rapid and specific LC-MS method for evaluating the stability of three potentially active antibacterial triazolylmethyl oxazolidinone compounds, namely PH-27, PH-38 and PH-41, in human plasma.

Methods: Ion-trap mass spectrometry using +APCI-MS at m/z 348.

Homologous housekeeping proteins in Nocardia--the NoDaMS proteomic database.

Nocardiosis is on the rise but hard to diagnose and the application of advanced subtyping technologies is called for. While the genomic sequence for the most virulent strain, Nocardia farcinica is available, proteome data are essentially non-existent. Nevertheless, they are necessary for functional studies on virulence and disease prevention.

LC-MS/MS determination of Synercid injections.

Synercid is a combination of two semisynthetic pristinamycin derivatives, quinupristin and dalfopristin in 30:70 (w/w) ratio. A rapid and specific high-performance liquid chromatography-mass spectrometry was developed for the determination of quinupristin and dalfopristin using positive electrospray tandem mass spectrometry (+ESI-MS/MS). Multiple reaction monitoring transitions at 1023.

Development of LC-MS method for determination of ursolic acid: application to the analysis of ursolic acid in Staphylea holocarpa Hemsl.

Ursolic acid is a hydroxy pentacyclic triterpene, which has a chemoprotective activity in human. A reliable and reproducible liquid chromatography-mass spectrometric assay (LC-MS) was developed for the determination of ursolic acid in laboratory-made mixtures and in leaves and twigs extracts of Staphylea holocarpa Hemsl. The methanolic solution of the extracted ursolic acid was chromatographically analyzed using Shim Pack CLC-CN, C18 (150 x 6 mm, 5 mu) column and a mobile consisting of methanol-1% acetic acid solution (4:1) at a flow rate of 1.

LC/MS determination of the enaminones E139, DM5 and DM27 in rat serum.

Enaminones, E139, DM5 and DM27, have been recently recognized as potential anticonvulsant compounds. The molecular masses of these enarminones were proven using ion trap Finnigan mass spectrometer. For conduction of biological studies in animals, a sensitive and selective high-performance liquid chromatography-mass spectrometry (LC/MS) was developed for the determination of the selected enaminones in rat serum.

Stability study of the anticonvulsant enaminone (E118) using HPLC and LC-MS.

The stability of the new chemical synthetic enaminone derivative (E118) was investigated using a stability-indicating high-performance liquid chromatography (HPLC) procedure. The examined samples were analyzed using a chiral HSA column and a mobile phase (pH 7.5) containing n-octanoic acid (5 mM), isopropyl alcohol and 100 mM disodium hydrogen phosphate solution (1:9 v/v) at a flow rate of 1 ml min(-1).