Synthesis and antibacterial activity of N-(5-benzylthio-1,3,4-thiadiazol-2-yl) and N-(5-benzylsulfonyl-1,3,4-thiadiazol-2-yl)piperazinyl quinolone derivatives

A series of N-(5-benzylthio-1,3,4-thiadiazol-2-yl) and N-(5-benzylsulfonyl-1,3,4-thiadiazol-2-yl) derivatives of piperazinyl quinolones was synthesized and evaluated for antibacterial activity against Gram-positive and Gram-negative microorganisms. Some of these derivatives exhibit high activity against Gram-positive bacteria; Staphylococcus aureus and Staphylococcus epidermidis, comparable or more potent than their parent N-piperazinyl quinolones norfloxacin and ciprofloxacin as reference drugs. The SAR of this series indicates that both the structure of the benzyl unit and the S or SO2 linker dramatically impact antibacterial activity

Synthesis and antibacterial activity of N-(5-benzylthio-1,3,4-thiadiazol-2-yl) and N-(5-benzylsulfonyl-1,3,4-thiadiazol-2-yl)piperazinyl quinolone derivatives

A series of N-(5-benzylthio-1,3,4-thiadiazol-2-yl) and N-(5-benzylsulfonyl-1,3,4-thiadiazol-2-yl) derivatives of piperazinyl quinolones was synthesized and evaluated for antibacterial activity against Gram-positive and Gram-negative microorganisms. Some of these derivatives exhibit high activity against Gram-positive bacteria; Staphylococcus aureus and Staphylococcus epidermidis, comparable or more potent than their parent N-piperazinyl quinolones norfloxacin and ciprofloxacin as reference drugs. The SAR of this series indicates that both the structure of the benzyl unit and the S or SO2 linker dramatically impact antibacterial activity

Myasthenia gravis as a presenting feature in a patient with lung cancer: A case report

A male patient with muscle weakness had clinical findings of ptosis, diplopia, proximal leg weakness, and positive repetitive nerve stimulation (RNS) test. He demonstrated positive acetylcholine receptor antibody. This lung cancer patient was presenting myasthenia gravis. The causal association between non-small-cell lung cancer and non-thymomatous myasthenia gravis has not been clarified yet. To date, there has been no evidence supporting the speculation that association of myasthenia gravis with lung cancer might be one of the phenotypes of paraneoplastic syndrome

A Thermodynamic Micellization and Hemolysis Evaluation of Polysorbate Surfactants in Combination with Short-Chain Alcohols

Surface active agents have been used in many pharmaceutical formulations for different purposes as penetration enhancers. In this study, the penetration enhancement activity of four nonionic surfactants from polyoxyethylene sorbitan fatty acid esters alone and in combination with some short-chain alcohols on red blood cells were investigated. Hemolysis at different concentrations of each nonionic surfactant (0.1, 0.2, 0.5, 1, and 2) and ethanol, isopropyl alcohol, glycerol, and propylene glycol (0.5, 1, 2, 5, and 10 w/v) were investigated. Critical micelle concentration (CMC) and micellization thermodynamic parameters of tween 80 in presence of ethanol and glycerol at different concentrations were determined. The influence of the ethanol and glycerol on nonionic surfactant micelle formation was evaluated by determining CMC and micellization thermodynamic parameters of tween80 at different concentrations of alcohol-tween mixtures. The mixture of Tween 20 and glycerol have the lowest hemolytic activity while tween 80-ethanol mixture has the highest hemolysis activity. The self-aggregation of surfactant monomers was affected by short-chain alcohols. The structure breaking ability of alcohol and their interactions with the hydrophilic-hydrophobic groups of surfactants might be the main factors for changing the micelle formation. The CMCs of tween 80 was incremented by increasing the concentration of alcohol. The results indicated that by adding and increasing short chain alcohols the CMCs increased also the CMCs were increasing through raising the temperature (while in the presents of surfactants alone the CMCs decreased by raising temperature). © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature