Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Synthesis of 1,5-Disubstituted 1,2,3-Triazole Modified Azacoumarins(01. Izmir Institute of Technology, 2022) Çetin, Başak; Çağır, AliCancer is a deadly disease that threatens human health and all life, and it is still a serious problem despite all scientific studies for more than half a century. Pharmacophores are a part of the structure of a drug (or drug candidate) responsible from the biological activity. This thesis is related with the synthesis of novel compounds having two well-known pharmacophore structures, 1,2,3-triazole and 1-azacoumarin. Both structures can be found in the structure of many biologically active molecules. Triazole modified coumarin derivatives are scarce in the literature. In this study, we aimed to improve the synthetic route toward the synthesis of 1- azacoumarin derivative modified by 1,2,3-triazole group at position 4-. Synthesis starts with the conversion of methyl 4-chloroanthranilate to the corresponding 4-OH azacoumarin. Then it is transferred into the 4-OTf group by simply addition of Tf group to OH under basic condition. After Sonogashira reaction and removal of TMS group 4- alkynyl-1-azacoumarin was produced. At this point, conversion of alkyne into 1,5- disubstituted 1,2,3-triazole was examined in the presence of Cp2Ni-Xantphos and RuCl(COD)Cp* catalytic systems but all of trials were failed probably due to the presence of ester group close to the reaction site. In further studies, design of the molecule will be reperformed and ester group will be moved over phenyl rings in order to test its biological activity over cancer cell lines.Master Thesis Investigation of Anticancer Properties of Novel Mdm2 Inhibitors(Izmir Institute of Technology, 2021) Özdemir, Sefayi Merve; Çağır, AliCancer is one major disease causing death worldwide. Current cancer treatments are not %100 effective to cure for patients, yet. Thereby, the synthesis and discovery of new therapeutics have been important to improve the survival period of the cancer patients. There are many strategies for synthesis of cancer therapeutics. One of the most important strategy for cancer treatment is the reactivation of p53. MDM2 is a negative regulator of p53 in cell, because it causes the inactivation of p53. In this thesis, the anticancer and MDM2 inhibitory properties of ezetimibe, desfluoro ezetimibe and intermediates during ezetimibe synthesis (named as SM2-9) and a side product from the synthesis of benidipine (named as SM1) on prostate cancer (LnCAP, wild-type p53), breast cancer (MCF7, wild type p53) and uterus cancer (HeLa, wild type nonfunctional p53) cells were investigated. For this purpose, the cytotoxic, cytostatic and apoptotic properties of these compounds were determined. Compounds SM2, SM3, SM4 and SM6 demonstrated cytotoxic effects, whereas compounds SM5, SM8 and SM9 had cytostatic effects on three cells. Compound SM7 had no effect on these cells, up to 100 μM concentration. Compounds SM1 had cytostatic effect on MCF7 cells, but it showed no activity on other cells. Compounds SM8 and SM9 had strong cytostatic activity. Thus, the apoptotic properties of these compounds were examined by caspases 3/7 activation and Annexin-V FITC assays. Besides, MDM2 inhibitor profiles of these compounds were investigated by fluorescence polarization assay. This study provides novel and potential molecules for drug discovery in cancer treatmentMaster Thesis Studies Toward the Asymmetric Synthesis of Ester Functionalized Novel 1,4-Oxazepine Derivatives(01. Izmir Institute of Technology, 2021) Bozoğlu, Hülya; Çağır, AliThe MDM2/p53 is one of the most widely studied protein-protein interaction because of being a valuable target for the development of novel anticancer agents. MDM2 protein is the natural inhibitor of p53 protein which act as a tumor suppressor. When MDM2 is overexpressed, damaged DNA is allowed to replicate and therefore cancerous cells can be generated because p53 has lost of its activity. For this reason; maintaining the activity of wild-type p53 through inhibition of MDM2 can stop the proliferation of cancer cells. New drugs that inhibit this interaction are important for the treatment of cancer. The aim of the study is synthesize chiral 1,4-oxazepine-5-one derivatives. (R)-2-amino-2-(4-chlorophenyl)acetic acid was used as starting material for the synthesis. The first step was a trityl protection of amine with trityl chloride. Trityl protected amino acid was reduced to N-Trt amino alcohol with LiAlH4 then oxidized to aldehyde by using Dess-Martin periodinane. The resulting aldehyde was reacted with 3-chlorophenylmagnesium bromide. Up to this part of the synthesis, reactions were performed successfully. Then trityl group was removed by TFA and amino alcohol was obtained. Then addition of several α,β-unsaturated carbonyls to the deprotected amino alcohol was studied by coupling reagents such as HATU. Afterwards we performed some intramolecular cyclization attempts but all cyclization attempts were failed.Master Thesis Antiproliferative Properties of 2'-alkoxymethyl Substituted Klavuzon Derivatives(Izmir Institute of Technology, 2017) Yıldız, Mehmet Salih; Pesen Okvur, Devrim; Çağır, Ali; Çağır, Ali; Pesen Okvur, DevrimOne of the main objectives of studies on anticancer agents is that the agent is expected to show a high cytotoxic activity on cancer cells and show a less cytotoxic effect on the contrary in healthy cells or never show cytotoxic activity. (R)- goniothalamin, isolated from the Goniothalamus plant, is a styryl lactone and has been found to have a selective antiproliferative property on cancer cells in studies conducted. The Michael acceptor feature in the structure of goniothalamin is thought to be covalently bonded to the nucleophilic side chains of the enzymes and show activity in this way. In previous studies, it has been shown that 1-naphthyl substituted 5,6-dihydro- 2H-pyran-2-one derivatives and 4'-methyl klavuzon derivatives exhibit higher cytotoxic activity on cancer cells than goniothalamin. In this study, antiproliferative properties of newly synthesized 2'-alkoxymethyl substituted klavuzon derivatives have been examined and MIA PaCa-2 pancreatic cancer cell lines and HPDEC pancreatic healthy cell lines were used. MTT cell viability tests were performed at the first step of this study. As a result of this study, it has been observed that the 2'-isobutoxymethylklavuzon derivative has selective cytotoxic activity on the MIA PaCa-2 cell line. It showed activity at lower concentrations than goniothalamin. Cytotoxic activities of the compounds are associated with the size of the R group at position 2’-. Methoxymethyl substituted the worst selective activity among these compounds whereas isobutoxy derivative the best selective one. In the second stage of the study, the inhibition on topoisomerase I enzyme was studied. The 2'-alkoxymethyl klavuzon derivatives were found to have Topo I enzyme inhibition properties depending on concentration and time manner. The study continued with choices methoxy and isobutoxy derivatives and these two compounds caused an arrest at G1 phase and DNA damage. Also, isobutoxy derivative induced apoptosis in the MIA PaCa-2 pancreatic cancer cell lines.Master Thesis Investigation of the Effect of 4'-alkylıklavuzon Derivatives on Nucleotide Synthesis and Nucleocytoplasmic Transport(Izmir Institute of Technology, 2016) Kutluer, Meltem; Köksal, Mustafa; Çağır, Ali; Çağır, Ali; Köksal, MustafaIn anti-cancer agent development studies one of the most significant issue is to get an agent that specifically targets cancer cells without any effects on healthy cells. Goniothalamin, that is a styryl lactone isolated from Goniothalamus plant species, is an anti-cancer agent that has selective anti-proliferative activity on cancer cell lines. Klavuzon and derivatives, which can be thought as analogs of goniothalamin, are more cytotoxic in cancer cells compared to goniothalamin. Previous structure activity relationship studies implies that α,β-unsaturated δ-lactone moiety is the source of the biological activity. Since it behaves as Michael acceptor, in this thesis possible irreversible inhibitions of two separate intracellular targets are investigated. In the first part, thymineless death caused by possible thymidylate synthase inhibition has been studied. Anti-proliferative effect of 4’-methylklavuzon in HuH-7 cancer cell line was tested by using MTT. Viability of klavuzon treated cells did not changed significantly in the absence and presence of varying concentration of additional thymidine supplement, and it is concluded that thymineless death is not a crucial mechanism for klavuzon derivatives. In the second part, 4’-methylklavuzon and its derivatives were tested on HeLa cell line to investigate inhibitory effect on the nucleocytoplasmic transport. Immunocytochemistry was used to demonstrate nucleocytoplasmic localization of Riok2 protein which is transferred from nuclei to cytoplasm by CRM1 nuclear export protein. Successfully, all tested klavuzon derivatives inhibit CRM1 nuclear export protein. Potency of the inhibition depends on the size of the alkyl substituent at 4’- position of klavuzon.Master Thesis Syntheses of Novel 4'-alkyl Substituted Klavuzon Derivatives(Izmir Institute of Technology, 2015) Kanbur, Tuğçe; Çağır, AliStyryl lactones, which are compounds isolated from natural sources, are known for their cytotoxic property against variety cancer cell lines. Goniothalamin is a well known member of stryl lactones, include α,β-unsaturated δ-lactone in its structure. Being a α,β-unsaturated δ-lactone subunit is an important structural feature. Since, Goniothalamin has a selective cytotoxic property for cancer cell lines with no significant cytotoxic activity toward non-malignant cells. Recent studies show that naphthalen-1-yl substituted α,β-unsaturated δ-lactone derivative has slightly better cytotoxic activity than (R)-goniothalamin. As a result of that naphthalen-1-yl substituted α,β-unsaturated δ-lactones derivative was named as klavuzon by Çağır Research group. In this study it is aimed to synthesize 4’-alkyl substituted klavuzon derivatives. Syntheses were started with the Cu catalayzed addition of Grignard reagents to ethyl 4-(bromomethyl)-1-naphthoate to achieve alkyl substitution. For lactone synthesis a well-known three steps synthesis was used starting from aldehyde. Thus 1-naphthoate esters first reduced to alcohol then oxidized to aldehyde by using LiAlH4 and PCC. These aldehydes were reacted with allymagnesium bromide then formed alcohols were acrylated with acryloyl chloride to yield the corresponding esters. Finally, target molecules were synthesised by ring closing metathesis by using 2nd generation Grubbs’ catalyst.