Association with coregulators is the major determinant governing peroxisome proliferator-activated receptor mobility in living cells.

The nucleus is an extremely dynamic compartment, and protein mobility represents a key factor in transcriptional regulation. We showed in a previous study that the diffusion of peroxisome proliferator-activated receptors (PPARs), a family of nuclear receptors regulating major cellular and metabolic functions, is modulated by ligand binding. In this study, we combine fluorescence correlation spectroscopy, dual color fluorescence cross-correlation microscopy, and fluorescence resonance energy transfer to dissect the molecular mechanisms controlling PPAR mobility and transcriptional activity in living cells. First, we bring new evidence that in vivo a high percentage of PPARs and retinoid X receptors is associated even in the absence of ligand. Second, we demonstrate that coregulator recruitment (and not DNA binding) plays a crucial role in receptor mobility, suggesting that transcriptional complexes are formed prior to promoter binding. In addition, association with coactivators in the absence of a ligand in living cells, both through the N-terminal AB domain and the AF-2 function of the ligand binding domain, provides a molecular basis to explain PPAR constitutive activity.

3D QSAR studies of N-4-arylacryloylpiperazin-1-yl-phenyl-oxazolidinones: a novel class of antibacterial agents.

Three-dimensional QSAR studies for N-4-arylacryloylpiperazin-1-yl-phenyl-oxazolidinones were conducted using TSAR 3.3. The in vitro activities (MICs) of the compounds against Staphylococcus aureus ATCC 25923 exhibited a strong correlation with the prediction made by the model developed in the present study.

Novel 4-N-substituted aryl pent-2-ene-1,4-dione derivatives of piperazinyloxazolidinones as antibacterials.

A few substituted piperazinylphenyloxazolidinone compounds 6-13 having substitution on the distant nitrogen atom of piperazine ring scaffold have been synthesized and evaluated for their antibacterial activity in Gram-positive bacteria. A few compounds showed superior in vitro antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, and Streptococcus pyogenes than linezolid and eperezolid.

Novel Mannich ketones of oxazolidinones as antibacterial agents.

A few Mannich ketones of piperazinyl oxazolidinone derivatives have been synthesized and their antibacterial activity in various Gram-positive organisms such as Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecalis were evaluated by MIC determination. Compound 12 showed comparable activity (MIC) to linezolid and superior to eperezolid.

Novel tetrahydro-thieno pyridyl oxazolidinone: an antibacterial agent.

Synthesis of a number of 4,5,6,7-tetrahydro-thieno[3,2-c]pyridine substituted oxazolidinones have been reported. They have been screened against a panel of Gram-positive pathogens including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis. A SAR has been developed. Compound 15 showed comparable activity (MIC) to linezolid and superior to eperezolid.

Oxazolidinone: search for highly potent antibacterial.

A number of substituted piperazinyl oxazolidinone derivatives have been synthesized and their antibacterial activities were evaluated by MIC determination. A systematic SAR was carried out to get highly potent oxazolidinone derivatives.