Oya Unsal Tan

Bio: Oya Unsal Tan is an academic researcher from Hacettepe University. The author has contributed to research in topics: Antimycobacterial & Chemistry. The author has an hindex of 9, co-authored 17 publications receiving 243 citations.

Molecular Docking Studies and Biological Evaluation of Chalcone Based Pyrazolines as Tyrosinase Inhibitors and Potential Anticancer Agents

Abstract: Studies on the discovery of tyrosinase enzyme inhibitors and exploration for better cytotoxic agents remain an important line in drug discovery and development. A series of synthetic chalcones and pyrazoline derivatives was evaluated for their inhibitory effects on the diphenolase activity of mushroom tyrosinase. The effects of these compounds on proliferation and microtubule assembly were also evaluated in seven different cancer cell lines. The results revealed that some of the synthetic compounds showed significant inhibitory activity, with four compounds being more potent tyrosinase inhibitors than the reference standard inhibitor kojic acid. Several compounds were toxic to cancer cell lines. Compound 1a was found to possess the highest anticancer activity towards all cell lines with an IC50 in the range of 0.9–2.2 μM. Seven of the compounds showed considerable tubulin polymerization activity at a concentration of 25 μM. Molecular modeling studies of these synthetic compounds were performed to investigate their interactions with the tyrosinase enzyme. The structure–activity relationship (SAR) study using in-silico analysis matched well with the in vitro tumour cell inhibitory activity.

Biological activity and molecular docking studies of curcumin-related α,β-unsaturated carbonyl-based synthetic compounds as anticancer agents and mushroom tyrosinase inhibitors.

Abstract: Hyperpigmentation in human skin and enzymatic browning in fruits, which are caused by tyrosinase enzyme, are not desirable. Investigations in the discovery of tyrosinase enzyme inhibitors and search for improved cytotoxic agents continue to be an important line in drug discovery and development. In present work, a new series of 30 compounds bearing α,β-unsaturated carbonyl moiety was designed and synthesized following curcumin as model. All compounds were evaluated for their effects on human cancer cell lines and mushroom tyrosinase enzyme. Moreover, the structure–activity relationships of these compounds are also explained. Molecular modeling studies of these new compounds were carried out to explore interactions with tyrosinase enzyme. Synthetic curcumin-like compounds (2a–b) were identified as potent anticancer agents with 81–82% cytotoxicity. Five of these newly synthesized compounds (1a, 8a–b, 10a–b) emerged to be the potent inhibitors of mushroom tyrosinase, providing further insight into designing ...

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Molecular Docking and Structure-Based Drug Design Strategies

Abstract: Pharmaceutical research has successfully incorporated a wealth of molecular modeling methods, within a variety of drug discovery programs, to study complex biological and chemical systems. The integration of computational and experimental strategies has been of great value in the identification and development of novel promising compounds. Broadly used in modern drug design, molecular docking methods explore the ligand conformations adopted within the binding sites of macromolecular targets. This approach also estimates the ligand-receptor binding free energy by evaluating critical phenomena involved in the intermolecular recognition process. Today, as a variety of docking algorithms are available, an understanding of the advantages and limitations of each method is of fundamental importance in the development of effective strategies and the generation of relevant results. The purpose of this review is to examine current molecular docking strategies used in drug discovery and medicinal chemistry, exploring the advances in the field and the role played by the integration of structure- and ligand-based methods.

A comprehensive review on tyrosinase inhibitors.

Abstract: Tyrosinase is a multi-copper enzyme which is widely distributed in different organisms and plays an important role in the melanogenesis and enzymatic browning. Therefore, its inhibitors can be attractive in cosmetics and medicinal industries as depigmentation agents and also in food and agriculture industries as antibrowning compounds. For this purpose, many natural, semi-synthetic and synthetic inhibitors have been developed by different screening methods to date. This review has focused on the tyrosinase inhibitors discovered from all sources and biochemically characterised in the last four decades.

A Structure-Based Drug Discovery Paradigm.

Abstract: Structure-based drug design is becoming an essential tool for faster and more cost-efficient lead discovery relative to the traditional method. Genomic, proteomic, and structural studies have provided hundreds of new targets and opportunities for future drug discovery. This situation poses a major problem: the necessity to handle the “big data” generated by combinatorial chemistry. Artificial intelligence (AI) and deep learning play a pivotal role in the analysis and systemization of larger data sets by statistical machine learning methods. Advanced AI-based sophisticated machine learning tools have a significant impact on the drug discovery process including medicinal chemistry. In this review, we focus on the currently available methods and algorithms for structure-based drug design including virtual screening and de novo drug design, with a special emphasis on AI- and deep-learning-based methods used for drug discovery.