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A novel electroanalytical method has been developed for the quantification of hydrophobic lapatinib in the presence of non-ionic surfactant Triton X-100 on a glassy carbon electrode. Lapatinib presented three well-defined anodic peaks (Ep 1, Ep 2, and Ep 3) by square wave voltammetry. The oxidation behavior of Ep 1 and Ep 2 showed diffusion-adsorption mix controlled processes by cyclic voltammetry. The possible electro-oxidation mechanism is discussed. The stripping conditions and square wave voltammetry parameters were optimized. The sensitivity of the proposed method was increased in the presence of Triton X-100. The hydrophobic interaction between Triton-X-100 and lapatinib guaranteed that more drug molecules could rapidly reach the electrode surface. The adsorptive stripping square wave voltammetry exhibits a linear calibration range from 2.0 × 10−8 to 1.0 × 10−6 mol l−1 for both ip 1 and ip 2 in 0.1 M H2SO4. The developed method was applied for the quantification of lapatinib in serum sample and pharmaceutical dosage form with satisfactory accuracy and precision. In the serum sample, the values of LOD were found to be 5.71 × 10−9 and 2.79 × 10−9 mol l−1 for ip 1 and ip 2, respectively. The developed method shows excellent analytical performance with nano-level detection limits, simplicity, and green chemistry compatibility.

Objective: To examine the interactions of some 4,5-dihydro-1H-pyrazole derivatives, which are thought to have antiinflammatory effects, with cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) enzymes, docking studies were carried out on these enzymes.Material and Method: COX-1 enzyme (3KK6) and COX-2 enzyme (3LN1) were selected from the protein data bank for docking studies. The ligand and protein constructs were prepared using Autodock 1.5.6. AutoDock Vina was used to determining the binding affinity, and Discovery Studio 3.5 was utilised to analyse and display the docking results.Result and Discussion: As a result of the docking process on COX-1 and COX-2 enzymes, 4,5-Dihydro-1H-pyrazole derivatives were observed to interact with both enzymes. The 4,5-dihydro-1H-pyrazole ring was found to be important in its interactions with the COX-2 enzyme. The inclusion of a bulky group in the construct did not cause any problems in interaction with the COX-1 enzyme but eliminated some interactions with the COX-2 enzyme. To better elucidate the inhibition properties of enzymes, this study should be supported by in vitro and in vivo COX inhibition tests.

Amaç: Bu çalışmada öncelikle şalkonlar ve bu şalkon türevlerinin hidrazitler ile reaksiyonu sonucu halka kapanması ile oluşan 4,5-dihidro-1H-pirazol yapısındaki bileşikler sentez edilmiş ve sentezlenen tüm bileşiklerin antimikrobiyal ve antitüberküler etkileri araştırılmıştır.Gereç ve Yöntem: Benzaldehit ve asetofenon türevlerinin alkali ortamda metanol içindeki reaksiyonuyla elde edilen şalkonların, hidrazit türevleri ile etanol içindeki reaksiyonu sonucu 4,5-dihidro-1H-pirazol türevleri elde edilmiştir. Sentezlenen bu bileşiklerin antimikrobiyal etkileri mikrodilüsyon yöntemiyle, antitüberküler etkileri ise mikroplaka alamar mavisi deneyi ile saptanmıştır.Sonuç ve Tartışma: Comparing E. coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Pseudomonas aeruginosa izolat (gentamisine dirençli) ve Candida albicans'a karşı 4,5-dihidro-1H-pirazol yapısındaki bileşiklerin şalkonlardan daha etkili olduğu bulunmuştur. Staphylococcus aureus'a karşı ise şalkonlar 4,5-dihidro-1H-pirazol türevlerinden daha etkili bulunmuştur. Staphylococcus aureus izolat (MRSA)

Background: MAO and ChE enzymes are very critical enzymes which regulate the level of neurotransmitters such as acetylcholine and monoamines. Monoamine neurotransmitters and acetylcholine play a very important role in many physiological events. Increase or decrease in the amount of these neurotransmitters is observed in many central nervous system pathologies. Balancing the amount of these neurotransmitters is important in improving the progression of these diseases. Inhibitors of MAO and ChE enzymes are important in symptomatic therapy and delaying progression of a group of CNS disease manifested with memory loss, cognitive decline and psychiatric disturbances like depression. Objective: In this article, the relationship between CNS diseases and vital role of the enzymes, MAO and ChE, is discussed on the pathophysiologic basis, focusing on drug research. Conclusion: MAO and ChE enzymes are still a good target for the development of novel drug active substances with optimized pharmacokinetic and pharmacodynamic properties, which can maximize the benefits of current therapy modalities.