Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 2Citation - Scopus: 31-Octanol Is a Functional Impurity Modifying Particle Size and Photophysical Properties of Colloidal Zncdsse/Zns Nanocrystals(American Chemical Society, 2021) Sevim Ünlütürk, Seçil; Çağır, Ali; Varlıklı, Canan; Özçelik, SerdarImpurities in trioctylphophine (TOP) strongly affect nanocrystal synthesis. 1-Octanol among other contaminants in TOP is identified for the first time as a functional impurity by H-1 NMR. The deliberate addition of 1-octanol into trioctylphosphine reduced particle size and modified photophysical properties of ZnCdSSe/ZnS colloidal nanocrystals. NMR analysis furthermore revealed that 1-octanol is bonded to the nanocrystal surfaces. The ratio of integrals for the O-CH2 protons of 1-octanol, which is the lowest compared to the other ligands, suggests that 1-octanol plays a critical role to tune the particle size of nanocrystals. The increased amount of 1-octanol added into TOP reduces the particle size from 9.8 to 7.2 nm, causing a progressive blue shift in the UV-vis and PL spectra but leaving the alloy composition unaffected. The rate of nonradiative processes is enhanced with the amount of 1-octanol added into TOP, correlating with higher dislocation density observed in the nanocrystals. As a conclusion, 1-octanol is proposed as a functional impurity that varies particle size and nonradiative photophysical processes in the ZnCdSSe/ZnS colloidal nanocrystals.Article Citation - WoS: 2Citation - Scopus: 2Novel 2 '-alkoxymethyl Substituted Klavuzon Derivatives as Inhibitors of Topo I and Crm1(Academic Press, 2020) Çetinkaya, Hakkı; Yıldız, Mehmet Salih; Kutluer, Meltem; Alkan, Aylin; Otaş, Hasan Ozan; Çağır, AliIn this work, 2'-alkoxymethyl substituted klavuzon derivatives were prepared starting from 2-methyl-1-naphthoic acid in eight steps. Anticancer potencies of the synthesized compounds were evaluated by performing MTT cell viability test over cancerous and healthy pancreatic cell lines, along with CRM1 inhibitory properties in HeLa cells by immunostaining and Topo I inhibition properties by supercoiled DNA relaxation assay. Their cytotoxic activities were also presented in hepatocellular carcinoma cells (HuH-7) derived 3D spheroids. Among the tested klavuzon derivatives, isobutoxymethyl substituted klavuzon showed the highest selectivity of cytotoxic activity against pancreatic cancer cell line. They showed potent Topo I inhibition while their CRM1 inhibitory properties somehow diminished compared to 4'-alkylsubstituted klavuzons. The most cytotoxic 2'-methoxymethyl derivative inhibited the growth of the spheroids derived from HuH-7 cell lines and PI staining exhibited time and concentration dependent cell death in 3D spheroids.Article 2’-Methylklavuzon Causes Lipid-Lowering Effects on A549 Non-Small Cell Lung Cancer Cells and Significant Changes on Dna Structure Evidenced by Fourier Transform Infrared Spectroscopy(Elsevier, 2020) Ceylan, Çağatay; Aksoy, Hatice Nurdan; Çağır, Ali; Çetinkaya, HakkıVarious chemical agents are used in the treatment of Non-Small Cell Lung Cancer (NSCLC). 2?-methylklavuzon was proposed as a potential chemotherapeutic agent in cancer treatment based on its topoisomerase inhibition activity. In this study the cellular effects of 2?-methylklavuzon was evaluated on A549 cancer cells using FTIR spectroscopy. 2?-methylklavuzon induced significant changes on both the whole cell lyophilizates and the lipid extracts of the A549 lung cancer cells. 2?-methylklavuzon caused significant structural changes in A549 cell DNA structure: T, A and G DNA breathing modes are lost after the drug application indicating the loss of topoisomerase activity. The level of transcription and RNA synthesis was enhanced. 2?-methylklavuzon induced single stranded DNA formation evidenced by the increase in the ratio of asymmetric/symmetric phosphate stretching modes. 2?-methylklavuzon induced band shifts only in the asymmetric mode of phosphate bonds not in the symmetrical phosphate bond stretching. 2?-methylklavuzon induced A form of DNA topography. In addition to the changes in the DNA structure and transcription 2?-methylklavuzon also caused lipid-lowering effect in A549 cancer cells. 2?-methylklavuzon suppressed lipid unsaturation, however, it induced formation of lipids with ring structures. 2?-methylklavuzon suppressed phosphate-containing lipids significantly and decreased carbonyl containing lipids and cholesterol slightly. 2?-methylklavuzon caused increases in the hydrocarbon chain length. Overall, 2?-methylklavuzon can be used as a lipid-lowering compound in the treatment of NSCLC and other cancer therapies. © 2020 Elsevier B.V.Article Citation - WoS: 3Citation - Scopus: 4Evaluation of Multifunctional Hybrid Analogs for Stilbenes, Chalcones and Flavanones(Bentham Science Publishers, 2017) Çağır, Ali; Odacı, Burcu; Varol, Mehmet; Akçok, İsmail; Okur, Özgür; Koparal, Ayşe T.Aims: In this study, discovery of novel anticancer agents acting by more than one mechanism was aimed. Method: For this purpose, eleven previously synthesized simple-stilbene, chalcone, flavanone derivatives and 31 novel stilbene-fused chalcones and stilbene-fused flavanones were tested for their aromatase inhibition, anti-angiogenic and anti-proliferative properties in cancer (PC3, MCF-7) and healthy (HUVEC) cell lines. MTT cell viability assay was used to evaluate the anti-proliferative activities of the compounds. CYP19/MFC high-throughput screening kit (BD Biosciences, Oxford, UK) was used to search the aromatase inhibition properties and matrigel tube formation assay was applied to determine the anti-angiogenic activities. Results: Results indicate that the simple-chalcone and flavanone derivatives were more cytotoxic than the simple-stilbenes in the both cancer cell lines. In contrast, the simple-stilbene structures were much more effective at aromatase inhibition. The cytotoxicity profiles of stilbene-fused chalcones in cancer cells imply that these molecules mostly mimic the simple chalcone structures. On the other hand, flavanones lose their cytotoxic activities after becoming fused with stilbenes. Additionally, aromatase inhibition assays showed that stilbene-fused chalcones again do mimic the simple-chalcones but not simple-stilbenes and anti-angiogenic profiles of the tested molecules seem to be not related with stilbene fragments. Furthermore, stilbene-fused flavanones may mimic both simple-flavanones and simple-stilbenes depending upon the type and position of the substituent in their respective terminal aromatic rings.Article Citation - WoS: 8Citation - Scopus: 9Crm1 Inhibitory and Antiproliferative Activities of Novel 4'-alkyl Substituted Klavuzon Derivatives(Elsevier Ltd., 2017) Kanbur, Tuğçe; Kara, Murat; Kutluer, Meltem; Şen, Ayhan; Delman, Murat; Alkan, Aylin; Otaş, Hasan Ozan; Akçok, İsmail; Çağır, AliKlavuzons are 6-(naphthalen-1-yl) substituted 5,6-dihydro-2H-pyran-2-one derivatives showing promising antiproliferative activities in variety of cancer cell lines. In this work, racemic syntheses of nine novel 4′-alkyl substituted klavuzon derivatives were completed in eight steps and anticancer properties of these compounds were evaluated. It is found that size of the substituent has dramatic effect over the potency and selectivity of the cytotoxic activity in cancerous and healthy pancreatic cell lines. The size of the substituent can also effect the CRM1 inhibitory properties of klavuzon derivatives. Strong cytotoxic activity and CRM1 inhibition can be observed only when a small substituent present at 4′-position of naphthalen-1-yl group. However, these substituents makes the molecule more cytotoxic in healthy pancreatic cells rather than cancerous pancreatic cells. Among the tested compounds 1,2,3,4-tetrahydrophenanthren-9-yl substituted lactone was the most cytotoxic compound and its antiproliferative activity was also tested in 3D spheroids generated from HuH-7 cell lines.Article Citation - WoS: 31Citation - Scopus: 346-Bicycloaryl Substituted (s)- and (r)-5,6 Asymmetric Synthesis, and Anti-Proliferative Properties(Elsevier Ltd., 2009) Kasaplar, Pınar; Yılmazer, Özgür; Çağır, Ali(R)-Goniothalamin, is a member of styryl lactones, possesses selective cytotoxicity against cancer cell lines. In this work, replacement of styryl substituent with 2-naphthyl and 3-quinoyl gave new analogues which may have less conformational changes compared to the lead compound. Anti-proliferative tests indicated that 2-naphthyl substituted (R)-5,6-dihydro-2H-pyran-2-one has slightly better cytotoxicity than (R)-goniothalamin. To clarify the effect of 2-naphthyl substituent additional aryl substituted (R)-5,6-dihydro-2H-pyran-2-ones have been synthesized enantioselectively and tested against PC-3 and MCF-7 cell lines.Article Citation - WoS: 24Citation - Scopus: 26Composition of Carotenoids in Scenedesmus Protuberans: Application of Chromatographic and Spectroscopic Methods(Springer Verlag, 2015) Erdoğan, Ayşegül; Çağır, Ali; Conk Dalay, Meltem; Eroğlu, Ahmet EminThis study aimed to identify and determine the carotenoids from green microalga, Scenedesmus protuberans using analytical techniques. Identification of carotenoids was realized by comparing their absorption and mass spectral data with those of reference standards available and reported values. Chromatographic data were then combined with the spectroscopic information. The separation of carotenoids was achieved by C30 column and high-performance liquid chromatography-diode array detection was used for their determination. In the present work, the carotenoid content of S. protuberans was found to be 1.45 mg/g of violaxanthin, 2.47 mg/g of all-trans-lutein, 0.15 mg/g of all-trans-α-carotene, 0.55 mg/g of all-trans-β-carotene, and 0.20 mg/g of 9 or 9′-cis-β-carotene. Due to lack of their standards, the amount of all-trans-loroxanthin and cis-isomers of other carotenoids could not be quantified. In order to validate the method, Certified Reference Material (BCR 485-Mixed vegetables) was used. In conclusion, this study can serve as a reference for the analysis of carotenoids in other microalgae.