... Zuhal GERÇEK (✉) Bülent Ecevit Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Zonguldak,... more ... Zuhal GERÇEK (✉) Bülent Ecevit Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Zonguldak, Türkiye Bülent Ecevit University, Faculty of Art ... Fakat enerji, zaman ve emek açısından ele alındığında, sorunu oluşturan etmenleri ortadan kaldırmak, sorunu çözmekten çok daha ...
Achmatowicz rearrangement was carried out with 2-chloro-1-(furan-2-yl) ethanol, which was synthes... more Achmatowicz rearrangement was carried out with 2-chloro-1-(furan-2-yl) ethanol, which was synthesized starting from 1-(furan-2-yl) ethanone. It was shown that the oxidation of 2-chloro-1-(furan-2-yl) ethanol with m-CPBA produced 2-(chloromethyl)-6-hydroxy-2H-pyran-3 (6H)-one in good yield (70%).
A novel benzimidazole‐imidazo[1,2‐a]pyridine hybrid; 2‐(imidazo[1,2‐a]pyridine‐8‐yl)benzimidazole... more A novel benzimidazole‐imidazo[1,2‐a]pyridine hybrid; 2‐(imidazo[1,2‐a]pyridine‐8‐yl)benzimidazole and its symmetrical bis‐ derivative 2,2′‐bis‐(imidazo[1,2‐a]pyridine‐8‐yl)‐1H,1H′‐[5,5′]‐bisbenzimidazole were synthesized and characterized. It was found that these two compounds have a strong DNA groove binding and peroxide mediated DNA‐cleavage properties. Furthermore, these molecules were screened against three different human cell lines namely HepG2, DLD‐1 and MDA‐MB‐231, and these compounds were found to have high cytotoxic activities.
Introduction It is known that drugs containing phenolic compounds are frequently used to treat di... more Introduction It is known that drugs containing phenolic compounds are frequently used to treat diseases such as diabetes, Alzheimer's, and cardiovascular diseases. One of the most abundant secondary metabolites in plants is phenolic compounds, such as simple phenols, phenolic acids, flavones, flavanones, and stilbenes. The main sources of phenolic compounds are fruits and vegetables, making up an important part of the human diet. According to the studies of the national health organization, due to the antioxidant effects of phenolic compounds found in herbal products, it has been revealed that rich fruit and vegetable consumption reduces the risks of diseases such as cancer, diabetes, Alzheimer's, and cardiovascular diseases [1]. Some benzoin compounds with the phenolic structure are found in fruits and vegetables in nature. The carbon-carbon bond formation is an important reaction in organic chemistry and studied extensively in the literature [2-5]. The benzoin condensation reaction is an important type of CC bond formation reaction and is widely used to synthesize natural compounds and analogs. Symmetric and asymmetric benzoin derivative synthesis using different catalysts in benzoin condensation have been studied under milder reaction conditions [2-15]. However, the condensation of two different benzaldehydes may have a widely different character; only the more stable form of the isomeric mixed benzoins could be isolable in excess. When the carbonyl group is adjacent to the phenyl ring with the more electrondonating substituent, it is consistent with the reversibility of the reaction and the relative stability of the carbonyl groups in the possible products [16]. In the literature, the synthesis of mixed benzoin had been made by a variety of methods involving the generation of a "masked" acyl carbanion, which reacts with aromatic aldehydes [17], the addition of an excess of the Grignard reagent to a cyanohydrin or a protected cyanohydrin of an aromatic aldehyde [18], and reduction of unsymmetrical benzils [19]. Thus, all of the mixed benzoin synthesis involve masking or unmasking steps. A literature search showed that various synthetic methods were reported for the benzil syntheses [20-22]. Diphenyl alkynes were oxidized efficiently to yield the corresponding benzil [23]. In another work, the selective addition of
5-Chloro-3-penten-2-one reacts with the amino group of homochiral amines, amino alcohols, amino a... more 5-Chloro-3-penten-2-one reacts with the amino group of homochiral amines, amino alcohols, amino acid esters to form corresponding 2-pyrrole derivatives in good yield and without racemization. (~) 1997 Elsevier Science Ltd. All rights reserved. Homochiral pyrrole derivatives of amines and amino acids are important starting materials for the synthesis of many different biologically active compounds. A stereoselective approach to the synthesis of indolizidine alkaloids, based on the reduction of bicyclic pyrroles, has been reported I. Paal-Knorr synthesis starting from primary amines and 1,4-dicarbonyl compounds and their masked equivalents such as tetrahydro-2,5-dimethoxyfuran is often used for the construction of pyrrole rings 2. During the condensation reaction for the formation of pyrrole ring with amino acids, partial racemization often occurs. We have developed a convenient method for the construction of different substituted pyrrole rings from amines, amino alcohols and amino acids with chloroenones prepared from acid chlorides and allylchlorides in the presence of AIC133 (Scheme 1). NH2 R4~R5 R1..~R2-~ ~ R3" ~N" RI"~R2 Scheme 1.
Introduction The most interested subject in 2020 is corona virus disease, which was named as COVI... more Introduction The most interested subject in 2020 is corona virus disease, which was named as COVID-19 by the WHO (World Health Organization) on the February 11, 2020 [1], This novel coronavirus is called as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by the international virus classification commission. Viruses in the corona family cause diseases in respiratory, gastrointestinal, hepatic, and central nervous system in both humans and animals [2]. Due to the respiratory transmission of SARS-CoV-2 from person to person, it has led to the formation of pandemic conditions in a short time. The world has become familiar with corona virus first with SARS (Severe Acute Respiratory Syndrome) epidemic, and then with the MERS (Middle East Respiratory Syndrome) epidemic [3]. The cause of pneumonia in COVID-19 cases is revealed as unique b-CoV strain [4]. The scientific world does not have an approved treatment specific to SARS-CoV-2. Luckily, it was shown that the novel b-CoV shows 88% similarity to the (SARS)-like coronaviruses, and about 50% to the MERS CoV. Therefore, drugs used for SARS and MERS have come forth again [5]. There are many potential drug candidates for the treatment of COVID-19 such as, oseltamivir [2], lopinavir/ ritonavir [6, 7], nucleoside analogues and nucleotide inhibitors [8] remdesivir [6, 9], tenofovir, ribavirin, sofosbuvir, galidesivir [10] antibiotics [11] and chloroquine and hydroxychloroquine [12,13]. Alternatively, various phytochemicals were used against SARS-CoV-2 virus too. Examples are, belachinal, macaflavanone E and vibsanol B [14], flavone and coumarine derivatives [15], saikosaponins [16], crocin, digitoxigenin, and ß-eudesmol [17], d-viniferin, myricitrin, Taiwan homoflavone A, lactucopicrin 15-oxalate, nymfolide A, afzelin, biorobin, hesperidin and phyllaemblicin B [18], and theophylline derivatives [19]. Hydroxychloroquine, which is mainly used for the treatment of malaria [20] was the first drug to be considered suitable for use in the treatment of COVID-19. On 17 June 2020, WHO announced that the research examining the effects of hydroxychloroquine in the treatment of COVID-19 was cancelled. It has been reported that the drug does not have a positive effect on the mortality rate and duration of hospital stay compared to standard treatments [21]. On July 1, 2020 FDA (Food and Drug Administration) issued a warning stating that hydroxychloroquine causes heart rhythm problems, blood and lymph system disorders, kidney injuries, and liver problems and failure [22]. Remdesivir is an antiviral drug that block viral RNA synthesis of RNA viruses such as SARS and MERS. The antiviral efficacy of the drug has been proven in many in vitro studies [23, 24]. However, it has not been approved for the COVID-19 treatment yet. As the emergency situation continues, FDA has issued an authorization on the use of the drug on hospitalized patients receiving COVID-19 treatment [22].
A general procedure was developed for the annelation of a butenolide to an aromatic ketone that h... more A general procedure was developed for the annelation of a butenolide to an aromatic ketone that highlighted a manganese(III) oxidation of aromatic ketones. The oxidation of aromatic ketones with manganese(III) acetate in the presence of 2-bromoacetic acid or the Mn(II) salt of this carboxylic acid provided a regioselectively convenient synthesis of 2-(2-bromoacetoxy) ketones. An Arbuzov or Wittig reaction of 2-(2-bromoacetoxy) ketones followed by cyclisation furnished 4arylfuran-2(SH)-ones in good yield.
A general procedure was developed for the annelation of a butenolide to an aromatic ketone that h... more A general procedure was developed for the annelation of a butenolide to an aromatic ketone that highlighted a manganese(III) oxidation of aromatic ketones. The oxidation of aromatic ketones with manganese(III) acetate in the presence of 2-bromoacetic acid or the Mn(II) salt of this carboxylic acid provided a regioselectively convenient synthesis of 2-(2-bromoacetoxy) ketones. An Arbuzov or Wittig reaction of 2-(2-bromoacetoxy) ketones followed by cyclisation furnished 4arylfuran-2(SH)-ones in good yield.
Kurumsal sosyal sorumluluk, kurumların toplumun yaşam kalitesini arttırmak amacıyla, çalışanları,... more Kurumsal sosyal sorumluluk, kurumların toplumun yaşam kalitesini arttırmak amacıyla, çalışanları, yerel halk ve bütün toplumla birlikte sürdürülebilir bir dünya için ekonomik, çevresel, kültürel ve sosyal gelişmeye destek verme sorumluluğudur. Şirketlerin tüm paydaşlarına ve topluma karşı etik ve sorumlu davranması, bu yönde kararlar alması ve uygulamasıdır. Üniversiteler kurumsal sosyal sorumlulukta nasıl yer almalıdır? Yenidünya, misyonlarını ve vizyonlarını yeniden tanımlayan, düşünce ve yaratıcılık için bir alan olarak görev yapmaya devam ederken, sosyal analiz, kritik düşünme ve sürdürülebilirlik için gerekli araçlar sağlayan bir üniversite anlayışına ihtiyaç duymaktadır. Temel görevleri eğitim ve araştırma olan üniversiteler, yaş aralığı 18'den 70'e kadar değişen, eğitim düzeyleri ilkokuldan doktoraya kadar çeşitlenen her cinsten ve kültürden bireylerin yer aldığı toplumun bir prototipini oluşturmaktadır. Bu bakımdan üniversiteler, toplumsal ve fiziksel çevrenin bugünü ve yarınını şekillendiren dinamiğin de bir parçası olmalıdır. Üniversiteler öncelikle gerçek Kurumsal Sosyal Sorumluluk kültürünü kendi bünyelerinde gerçekleştirmekle işe başlamalıdır. Üniversitelerin en önemli paydaşlarından olan öğrenci kitlesi üzerinde, üniversitelerin temel işlevlerinden biri olan eğitim konusunda ilk atılım gerçekleştirilmelidir. Gerçek eğitim, kendini tanıma ve öğrenme sürecini, kişisel gelişimi teşvik etmenin ve insanlara toplum içindeki yerlerini bulmada yol göstermenin yanı sıra toplulukları güçlendiren ve sosyal gelişimi harekete geçiren bir işlemdir. Eğitim, bireylerin hayata özgür ve aktif katılımlarını telkin, teşvik ve motive etmelidir. Fiziksel ve sosyal çevrelerindeki problemlere yeni yaklaşımlar oluşturabilecek yeteneklerle donatmalıdır. Eğitim kişisel, toplumsal ve evrensel bilincin gelişimini sağlamalıdır. Bu bilinçle donatılmış ve bu kavramı deneyimlemiş bireylerin oluşturduğu bir dünyada sosyal sorumluluk, artık hayatın doğal bir parçası halinde yaşanacaktır.
Butenolide Anellation Using a Manganese(III) Oxidation. A Synthesis of Chromolaenin (Laevigatin).... more Butenolide Anellation Using a Manganese(III) Oxidation. A Synthesis of Chromolaenin (Laevigatin).-A novel facile approach to the butenolide anellation to an aromatic ketone is presented. The procedure starts with the oxidation of tetralones (I) with Mn(O-Ac) 3 in the presence of free α-halopropanoic acid (II) to provide, after subsequent O-acylation, the α-propanoyloxy ketones (III) in good yields. Arbuzov phosphorylation and Horner-Wadsworth-Emmons cyclization then afford the anellated butenolides (VI). Chromolaenin (VII) is finally obtained using a previously described
Butenolide Anellation Using a Manganese(III) Oxidation. A Synthesis of Chromolaenin (Laevigatin).... more Butenolide Anellation Using a Manganese(III) Oxidation. A Synthesis of Chromolaenin (Laevigatin).-A novel facile approach to the butenolide anellation to an aromatic ketone is presented. The procedure starts with the oxidation of tetralones (I) with Mn(O-Ac) 3 in the presence of free α-halopropanoic acid (II) to provide, after subsequent O-acylation, the α-propanoyloxy ketones (III) in good yields. Arbuzov phosphorylation and Horner-Wadsworth-Emmons cyclization then afford the anellated butenolides (VI). Chromolaenin (VII) is finally obtained using a previously described
European journal of advanced chemistry research, May 28, 2022
Three novel compounds, namely, 4-amino-5-(2,3,4,5,6-pentahydroxy-1-(4oxo-2-thioxo-1,2,3,4-tetrahy... more Three novel compounds, namely, 4-amino-5-(2,3,4,5,6-pentahydroxy-1-(4oxo-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-yl)hexyl)-2-thioxo-2,3dihydropyrimidin-4(1H)-one SG-3, 3-methyl-5-(2,3,4,5,6-pentahydroxy-1-(4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-yl)hexyl)-2-thioxo-2,3dihydropyrimidin-4(1H)-one-(2H)-ylamino)butanoic acid SG-4 and 2-(4oxo-5-(2,3,4,5,6-pentahydroxy-1-(4-oxo-2-thioxo-1,2,3,4tetrahydropyrimidin-5-yl)hexyl)-2-thioxo-2,3-dihydropyrimidin-4(1H)one-2-phenylacetic acid SG-6 were synthesized from easily available, inexpensive, environmentally friendly starting materials (glucose, amino acid and thiobarbutric acid) and characterized by 1 H-NMR, 13 C-NMR and mass spectroscopy. the molecular modelling of these compounds was studied in Crystal structure of vaccinia virus thymidylate kinase , for the treatment of variola. Their binding motifs and drug-like properties were investigated. Results show that all compounds confirmed appropriate binding free energies; between-9.71 and-10.11 Kcal/mol. Since the novel molecules have high ligand-receptor binding interactions, they can be a powerful alternative to FDA approved drug Cidofovir.
Enzyme catalyzed transesterification of rac-2-chloro-1-(2-furyl)ethanol rac-1 using vinyl acetate... more Enzyme catalyzed transesterification of rac-2-chloro-1-(2-furyl)ethanol rac-1 using vinyl acetate afforded the enantiomers of 2-chloro-1-(2-furyl)ethanol 1 and 2-chloro-1-(2-furyl)ethyl acetate 2 in high enantiomeric excess. Several lipases were used for the kinetic resolution of racemic 2-chloro-1-(2-furyl)ethanol l, in which the lipases from Pseudomonas cepacia, Candida antarctica and Candida cylindracea displayed high enantioselectivity towards 1.
Bodipy dyes with n-decyloxyphenyl-(4, 5) and pentadecyl-(8) meso substituents can easily embed th... more Bodipy dyes with n-decyloxyphenyl-(4, 5) and pentadecyl-(8) meso substituents can easily embed themselves into micellar structures formed from Cremophor-EL. In micelles of approximately 20 nm median size, heavy-atom substituted dyes show remarkable photosensitization properties as evidenced by the rate of reaction with an anthracene-based selective singlet oxygen trap in buffered aqueous solutions. Considering the ease of Bodipy derivatization and the advantages of Cremophor-EL carried therapeutic agents, these photosensitizing agents may offer novel targeting opportunities and enhanced chemical and photophysical stability.
The synthesis of a novel copper (II) complex, namely, [Cu(phen)(NO2-impi)]2+ (where phen is 1,10-... more The synthesis of a novel copper (II) complex, namely, [Cu(phen)(NO2-impi)]2+ (where phen is 1,10-phenanthroline; NO2-impi is 2-(2-(4-nitrophenyl)-5-(pyridin-2-yl)-1H-imidazol-4-yl) pyridine, ZU-3, was performed. UV titration and viscosity measurements were used to determine its interaction with ds-DNA. The binding constant of complex to ds-DNA was 1.3x105 M-1. The Stern-Volmer extinction constant (KSV) for ZU-3 was calculated as 1.2 x 105 M-1. The complex was screened against five human cell lines, namely A 549, PC-3, BEAS-2B, HCT-116 and MDZMB-231, and it was found that ZU-3 shows selective cytotoxicity on colon cancer cells. It has been found that ZU-3 reduced HCT-116 cell density and caused pyknotic morphology that are associated with cell death by apoptosis.
Journal of Photochemistry and Photobiology B: Biology, 2018
, DNA binding and cytotoxic activity of pyrimido[4′,5′:4,5]thieno (2,3-b)quinoline with 9-hydroxy... more , DNA binding and cytotoxic activity of pyrimido[4′,5′:4,5]thieno (2,3-b)quinoline with 9-hydroxy-4-(3-diethylaminopropylamino) and 8-methoxy-4-(3-diethylaminopropylamino) substitutions
Manisa Celal Bayar üniversitesi eğitim fakültesi dergisi, Sep 2, 2012
Bu çalışmanın amacı, yapılandırılmış kimya laboratuar çalışmalarının ortaokul öğrencilerinin bili... more Bu çalışmanın amacı, yapılandırılmış kimya laboratuar çalışmalarının ortaokul öğrencilerinin bilimsel araştırmalara yönelik algıları üzerine etkisini araştırmaktır. Olasılıksız uygun örneklemin kullanıldığı bu çalışmaya 60 ortaokul 6 ve 7. sınıf öğrencisi katılmış, bu öğrencilerden çalışmayı tamamlayan 48'inden toplanan veriler üzerinde istatistiksel işlemler yapılmıştır. Öğrencilerin bilimsel araştırma algıları VOSI-E ölçeği ile ölçülmüştür. Çalışma sonunda, yapılandırılmış kimya laboratuar çalışmalarının cinsiyet ve sınıf düzeylerine göre öğrencilerin sahip oldukları bilimsel araştırma algıları üzerinde bir etkisinin olmadığı anlaşılmıştır. Bilim okuryazarı bireyler yetiştirmek olan fen eğitiminde öğrencilerin bilimsel araştırma algılarının artırılmasında yapılandırılmış laboratuar çalışmalarının olumlu katkısının olmadığı, bu amaçla açık uçlu veya araştırmaya dayalı yöntemlerin daha etkin sonuçlar verebileceği önerilmektedir.
European journal of advanced chemistry research, Oct 22, 2022
I. INTRODUCTION Around 100 years ago people lived to the age of 30 on average. Improved economic ... more I. INTRODUCTION Around 100 years ago people lived to the age of 30 on average. Improved economic conditions, changes in diet and lifestyle, adjustments in work and social factors, as well as improved public health strategies and regulation of medical care, increase the average life expectancy to 71.5 years today [1]. Prolongation of life leads to common chronic diseases of older people such as cancer, cardiovascular diseases, and Alzheimer's diseases, are becoming much more prevalent. Alzheimer's disease (AD) was first defined by Dr. Alois Alzheimer in 1907 [2], [3]. Today, Alzheimer's disease (AD) is the third most expensive disease in the United States, costing society approximately $100 billion each year [4]. Although the cause of AD is still a mystery, many theories have been proposed for the causes of it [5], [6]. For example, acceleration of aging, anatomical pathways degenerations, mitochondrial and immune system dysfunctions, environmental and genetic factors, b-amyloid formation can be counted as the factors that lead to the disease [7]-[12]. Although the disease is still not curable with current clinical therapy, the treatment with glutamate receptor-selective drugs, antioxidants, inhibitors of nitric oxide synthase, calcium channel antagonists, receptor or enzyme inhibitors, and growth factors are promising approaches for slowing disease. Oxidative stress which can be defined as the imbalance between the antioxidant mechanism and the intracellular production of free radicals/reactive oxygen species (ROS), is a potential source of damage to vital molecules such as DNA, lipids, sugars, and proteins within cells. Its role in the pathogenesis and pathophysiology of cardiovascular, neurodegenerative, oncological, inflammatory, etc. diseases have been argued in the literature [13], [14]. Animal and human studies in the literature show the important role of oxidative damage occurring before symptoms occur and both b-amyloid-containing plaques and neurofibrillary tangles form in Alzheimer's disease [11], [15]. Therefore, the use of antioxidants can prevent or slow the progression of Alzheimer's disease.
... Zuhal GERÇEK (✉) Bülent Ecevit Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Zonguldak,... more ... Zuhal GERÇEK (✉) Bülent Ecevit Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Zonguldak, Türkiye Bülent Ecevit University, Faculty of Art ... Fakat enerji, zaman ve emek açısından ele alındığında, sorunu oluşturan etmenleri ortadan kaldırmak, sorunu çözmekten çok daha ...
Achmatowicz rearrangement was carried out with 2-chloro-1-(furan-2-yl) ethanol, which was synthes... more Achmatowicz rearrangement was carried out with 2-chloro-1-(furan-2-yl) ethanol, which was synthesized starting from 1-(furan-2-yl) ethanone. It was shown that the oxidation of 2-chloro-1-(furan-2-yl) ethanol with m-CPBA produced 2-(chloromethyl)-6-hydroxy-2H-pyran-3 (6H)-one in good yield (70%).
A novel benzimidazole‐imidazo[1,2‐a]pyridine hybrid; 2‐(imidazo[1,2‐a]pyridine‐8‐yl)benzimidazole... more A novel benzimidazole‐imidazo[1,2‐a]pyridine hybrid; 2‐(imidazo[1,2‐a]pyridine‐8‐yl)benzimidazole and its symmetrical bis‐ derivative 2,2′‐bis‐(imidazo[1,2‐a]pyridine‐8‐yl)‐1H,1H′‐[5,5′]‐bisbenzimidazole were synthesized and characterized. It was found that these two compounds have a strong DNA groove binding and peroxide mediated DNA‐cleavage properties. Furthermore, these molecules were screened against three different human cell lines namely HepG2, DLD‐1 and MDA‐MB‐231, and these compounds were found to have high cytotoxic activities.
Introduction It is known that drugs containing phenolic compounds are frequently used to treat di... more Introduction It is known that drugs containing phenolic compounds are frequently used to treat diseases such as diabetes, Alzheimer's, and cardiovascular diseases. One of the most abundant secondary metabolites in plants is phenolic compounds, such as simple phenols, phenolic acids, flavones, flavanones, and stilbenes. The main sources of phenolic compounds are fruits and vegetables, making up an important part of the human diet. According to the studies of the national health organization, due to the antioxidant effects of phenolic compounds found in herbal products, it has been revealed that rich fruit and vegetable consumption reduces the risks of diseases such as cancer, diabetes, Alzheimer's, and cardiovascular diseases [1]. Some benzoin compounds with the phenolic structure are found in fruits and vegetables in nature. The carbon-carbon bond formation is an important reaction in organic chemistry and studied extensively in the literature [2-5]. The benzoin condensation reaction is an important type of CC bond formation reaction and is widely used to synthesize natural compounds and analogs. Symmetric and asymmetric benzoin derivative synthesis using different catalysts in benzoin condensation have been studied under milder reaction conditions [2-15]. However, the condensation of two different benzaldehydes may have a widely different character; only the more stable form of the isomeric mixed benzoins could be isolable in excess. When the carbonyl group is adjacent to the phenyl ring with the more electrondonating substituent, it is consistent with the reversibility of the reaction and the relative stability of the carbonyl groups in the possible products [16]. In the literature, the synthesis of mixed benzoin had been made by a variety of methods involving the generation of a "masked" acyl carbanion, which reacts with aromatic aldehydes [17], the addition of an excess of the Grignard reagent to a cyanohydrin or a protected cyanohydrin of an aromatic aldehyde [18], and reduction of unsymmetrical benzils [19]. Thus, all of the mixed benzoin synthesis involve masking or unmasking steps. A literature search showed that various synthetic methods were reported for the benzil syntheses [20-22]. Diphenyl alkynes were oxidized efficiently to yield the corresponding benzil [23]. In another work, the selective addition of
5-Chloro-3-penten-2-one reacts with the amino group of homochiral amines, amino alcohols, amino a... more 5-Chloro-3-penten-2-one reacts with the amino group of homochiral amines, amino alcohols, amino acid esters to form corresponding 2-pyrrole derivatives in good yield and without racemization. (~) 1997 Elsevier Science Ltd. All rights reserved. Homochiral pyrrole derivatives of amines and amino acids are important starting materials for the synthesis of many different biologically active compounds. A stereoselective approach to the synthesis of indolizidine alkaloids, based on the reduction of bicyclic pyrroles, has been reported I. Paal-Knorr synthesis starting from primary amines and 1,4-dicarbonyl compounds and their masked equivalents such as tetrahydro-2,5-dimethoxyfuran is often used for the construction of pyrrole rings 2. During the condensation reaction for the formation of pyrrole ring with amino acids, partial racemization often occurs. We have developed a convenient method for the construction of different substituted pyrrole rings from amines, amino alcohols and amino acids with chloroenones prepared from acid chlorides and allylchlorides in the presence of AIC133 (Scheme 1). NH2 R4~R5 R1..~R2-~ ~ R3" ~N" RI"~R2 Scheme 1.
Introduction The most interested subject in 2020 is corona virus disease, which was named as COVI... more Introduction The most interested subject in 2020 is corona virus disease, which was named as COVID-19 by the WHO (World Health Organization) on the February 11, 2020 [1], This novel coronavirus is called as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) by the international virus classification commission. Viruses in the corona family cause diseases in respiratory, gastrointestinal, hepatic, and central nervous system in both humans and animals [2]. Due to the respiratory transmission of SARS-CoV-2 from person to person, it has led to the formation of pandemic conditions in a short time. The world has become familiar with corona virus first with SARS (Severe Acute Respiratory Syndrome) epidemic, and then with the MERS (Middle East Respiratory Syndrome) epidemic [3]. The cause of pneumonia in COVID-19 cases is revealed as unique b-CoV strain [4]. The scientific world does not have an approved treatment specific to SARS-CoV-2. Luckily, it was shown that the novel b-CoV shows 88% similarity to the (SARS)-like coronaviruses, and about 50% to the MERS CoV. Therefore, drugs used for SARS and MERS have come forth again [5]. There are many potential drug candidates for the treatment of COVID-19 such as, oseltamivir [2], lopinavir/ ritonavir [6, 7], nucleoside analogues and nucleotide inhibitors [8] remdesivir [6, 9], tenofovir, ribavirin, sofosbuvir, galidesivir [10] antibiotics [11] and chloroquine and hydroxychloroquine [12,13]. Alternatively, various phytochemicals were used against SARS-CoV-2 virus too. Examples are, belachinal, macaflavanone E and vibsanol B [14], flavone and coumarine derivatives [15], saikosaponins [16], crocin, digitoxigenin, and ß-eudesmol [17], d-viniferin, myricitrin, Taiwan homoflavone A, lactucopicrin 15-oxalate, nymfolide A, afzelin, biorobin, hesperidin and phyllaemblicin B [18], and theophylline derivatives [19]. Hydroxychloroquine, which is mainly used for the treatment of malaria [20] was the first drug to be considered suitable for use in the treatment of COVID-19. On 17 June 2020, WHO announced that the research examining the effects of hydroxychloroquine in the treatment of COVID-19 was cancelled. It has been reported that the drug does not have a positive effect on the mortality rate and duration of hospital stay compared to standard treatments [21]. On July 1, 2020 FDA (Food and Drug Administration) issued a warning stating that hydroxychloroquine causes heart rhythm problems, blood and lymph system disorders, kidney injuries, and liver problems and failure [22]. Remdesivir is an antiviral drug that block viral RNA synthesis of RNA viruses such as SARS and MERS. The antiviral efficacy of the drug has been proven in many in vitro studies [23, 24]. However, it has not been approved for the COVID-19 treatment yet. As the emergency situation continues, FDA has issued an authorization on the use of the drug on hospitalized patients receiving COVID-19 treatment [22].
A general procedure was developed for the annelation of a butenolide to an aromatic ketone that h... more A general procedure was developed for the annelation of a butenolide to an aromatic ketone that highlighted a manganese(III) oxidation of aromatic ketones. The oxidation of aromatic ketones with manganese(III) acetate in the presence of 2-bromoacetic acid or the Mn(II) salt of this carboxylic acid provided a regioselectively convenient synthesis of 2-(2-bromoacetoxy) ketones. An Arbuzov or Wittig reaction of 2-(2-bromoacetoxy) ketones followed by cyclisation furnished 4arylfuran-2(SH)-ones in good yield.
A general procedure was developed for the annelation of a butenolide to an aromatic ketone that h... more A general procedure was developed for the annelation of a butenolide to an aromatic ketone that highlighted a manganese(III) oxidation of aromatic ketones. The oxidation of aromatic ketones with manganese(III) acetate in the presence of 2-bromoacetic acid or the Mn(II) salt of this carboxylic acid provided a regioselectively convenient synthesis of 2-(2-bromoacetoxy) ketones. An Arbuzov or Wittig reaction of 2-(2-bromoacetoxy) ketones followed by cyclisation furnished 4arylfuran-2(SH)-ones in good yield.
Kurumsal sosyal sorumluluk, kurumların toplumun yaşam kalitesini arttırmak amacıyla, çalışanları,... more Kurumsal sosyal sorumluluk, kurumların toplumun yaşam kalitesini arttırmak amacıyla, çalışanları, yerel halk ve bütün toplumla birlikte sürdürülebilir bir dünya için ekonomik, çevresel, kültürel ve sosyal gelişmeye destek verme sorumluluğudur. Şirketlerin tüm paydaşlarına ve topluma karşı etik ve sorumlu davranması, bu yönde kararlar alması ve uygulamasıdır. Üniversiteler kurumsal sosyal sorumlulukta nasıl yer almalıdır? Yenidünya, misyonlarını ve vizyonlarını yeniden tanımlayan, düşünce ve yaratıcılık için bir alan olarak görev yapmaya devam ederken, sosyal analiz, kritik düşünme ve sürdürülebilirlik için gerekli araçlar sağlayan bir üniversite anlayışına ihtiyaç duymaktadır. Temel görevleri eğitim ve araştırma olan üniversiteler, yaş aralığı 18'den 70'e kadar değişen, eğitim düzeyleri ilkokuldan doktoraya kadar çeşitlenen her cinsten ve kültürden bireylerin yer aldığı toplumun bir prototipini oluşturmaktadır. Bu bakımdan üniversiteler, toplumsal ve fiziksel çevrenin bugünü ve yarınını şekillendiren dinamiğin de bir parçası olmalıdır. Üniversiteler öncelikle gerçek Kurumsal Sosyal Sorumluluk kültürünü kendi bünyelerinde gerçekleştirmekle işe başlamalıdır. Üniversitelerin en önemli paydaşlarından olan öğrenci kitlesi üzerinde, üniversitelerin temel işlevlerinden biri olan eğitim konusunda ilk atılım gerçekleştirilmelidir. Gerçek eğitim, kendini tanıma ve öğrenme sürecini, kişisel gelişimi teşvik etmenin ve insanlara toplum içindeki yerlerini bulmada yol göstermenin yanı sıra toplulukları güçlendiren ve sosyal gelişimi harekete geçiren bir işlemdir. Eğitim, bireylerin hayata özgür ve aktif katılımlarını telkin, teşvik ve motive etmelidir. Fiziksel ve sosyal çevrelerindeki problemlere yeni yaklaşımlar oluşturabilecek yeteneklerle donatmalıdır. Eğitim kişisel, toplumsal ve evrensel bilincin gelişimini sağlamalıdır. Bu bilinçle donatılmış ve bu kavramı deneyimlemiş bireylerin oluşturduğu bir dünyada sosyal sorumluluk, artık hayatın doğal bir parçası halinde yaşanacaktır.
Butenolide Anellation Using a Manganese(III) Oxidation. A Synthesis of Chromolaenin (Laevigatin).... more Butenolide Anellation Using a Manganese(III) Oxidation. A Synthesis of Chromolaenin (Laevigatin).-A novel facile approach to the butenolide anellation to an aromatic ketone is presented. The procedure starts with the oxidation of tetralones (I) with Mn(O-Ac) 3 in the presence of free α-halopropanoic acid (II) to provide, after subsequent O-acylation, the α-propanoyloxy ketones (III) in good yields. Arbuzov phosphorylation and Horner-Wadsworth-Emmons cyclization then afford the anellated butenolides (VI). Chromolaenin (VII) is finally obtained using a previously described
Butenolide Anellation Using a Manganese(III) Oxidation. A Synthesis of Chromolaenin (Laevigatin).... more Butenolide Anellation Using a Manganese(III) Oxidation. A Synthesis of Chromolaenin (Laevigatin).-A novel facile approach to the butenolide anellation to an aromatic ketone is presented. The procedure starts with the oxidation of tetralones (I) with Mn(O-Ac) 3 in the presence of free α-halopropanoic acid (II) to provide, after subsequent O-acylation, the α-propanoyloxy ketones (III) in good yields. Arbuzov phosphorylation and Horner-Wadsworth-Emmons cyclization then afford the anellated butenolides (VI). Chromolaenin (VII) is finally obtained using a previously described
European journal of advanced chemistry research, May 28, 2022
Three novel compounds, namely, 4-amino-5-(2,3,4,5,6-pentahydroxy-1-(4oxo-2-thioxo-1,2,3,4-tetrahy... more Three novel compounds, namely, 4-amino-5-(2,3,4,5,6-pentahydroxy-1-(4oxo-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-yl)hexyl)-2-thioxo-2,3dihydropyrimidin-4(1H)-one SG-3, 3-methyl-5-(2,3,4,5,6-pentahydroxy-1-(4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidin-5-yl)hexyl)-2-thioxo-2,3dihydropyrimidin-4(1H)-one-(2H)-ylamino)butanoic acid SG-4 and 2-(4oxo-5-(2,3,4,5,6-pentahydroxy-1-(4-oxo-2-thioxo-1,2,3,4tetrahydropyrimidin-5-yl)hexyl)-2-thioxo-2,3-dihydropyrimidin-4(1H)one-2-phenylacetic acid SG-6 were synthesized from easily available, inexpensive, environmentally friendly starting materials (glucose, amino acid and thiobarbutric acid) and characterized by 1 H-NMR, 13 C-NMR and mass spectroscopy. the molecular modelling of these compounds was studied in Crystal structure of vaccinia virus thymidylate kinase , for the treatment of variola. Their binding motifs and drug-like properties were investigated. Results show that all compounds confirmed appropriate binding free energies; between-9.71 and-10.11 Kcal/mol. Since the novel molecules have high ligand-receptor binding interactions, they can be a powerful alternative to FDA approved drug Cidofovir.
Enzyme catalyzed transesterification of rac-2-chloro-1-(2-furyl)ethanol rac-1 using vinyl acetate... more Enzyme catalyzed transesterification of rac-2-chloro-1-(2-furyl)ethanol rac-1 using vinyl acetate afforded the enantiomers of 2-chloro-1-(2-furyl)ethanol 1 and 2-chloro-1-(2-furyl)ethyl acetate 2 in high enantiomeric excess. Several lipases were used for the kinetic resolution of racemic 2-chloro-1-(2-furyl)ethanol l, in which the lipases from Pseudomonas cepacia, Candida antarctica and Candida cylindracea displayed high enantioselectivity towards 1.
Bodipy dyes with n-decyloxyphenyl-(4, 5) and pentadecyl-(8) meso substituents can easily embed th... more Bodipy dyes with n-decyloxyphenyl-(4, 5) and pentadecyl-(8) meso substituents can easily embed themselves into micellar structures formed from Cremophor-EL. In micelles of approximately 20 nm median size, heavy-atom substituted dyes show remarkable photosensitization properties as evidenced by the rate of reaction with an anthracene-based selective singlet oxygen trap in buffered aqueous solutions. Considering the ease of Bodipy derivatization and the advantages of Cremophor-EL carried therapeutic agents, these photosensitizing agents may offer novel targeting opportunities and enhanced chemical and photophysical stability.
The synthesis of a novel copper (II) complex, namely, [Cu(phen)(NO2-impi)]2+ (where phen is 1,10-... more The synthesis of a novel copper (II) complex, namely, [Cu(phen)(NO2-impi)]2+ (where phen is 1,10-phenanthroline; NO2-impi is 2-(2-(4-nitrophenyl)-5-(pyridin-2-yl)-1H-imidazol-4-yl) pyridine, ZU-3, was performed. UV titration and viscosity measurements were used to determine its interaction with ds-DNA. The binding constant of complex to ds-DNA was 1.3x105 M-1. The Stern-Volmer extinction constant (KSV) for ZU-3 was calculated as 1.2 x 105 M-1. The complex was screened against five human cell lines, namely A 549, PC-3, BEAS-2B, HCT-116 and MDZMB-231, and it was found that ZU-3 shows selective cytotoxicity on colon cancer cells. It has been found that ZU-3 reduced HCT-116 cell density and caused pyknotic morphology that are associated with cell death by apoptosis.
Journal of Photochemistry and Photobiology B: Biology, 2018
, DNA binding and cytotoxic activity of pyrimido[4′,5′:4,5]thieno (2,3-b)quinoline with 9-hydroxy... more , DNA binding and cytotoxic activity of pyrimido[4′,5′:4,5]thieno (2,3-b)quinoline with 9-hydroxy-4-(3-diethylaminopropylamino) and 8-methoxy-4-(3-diethylaminopropylamino) substitutions
Manisa Celal Bayar üniversitesi eğitim fakültesi dergisi, Sep 2, 2012
Bu çalışmanın amacı, yapılandırılmış kimya laboratuar çalışmalarının ortaokul öğrencilerinin bili... more Bu çalışmanın amacı, yapılandırılmış kimya laboratuar çalışmalarının ortaokul öğrencilerinin bilimsel araştırmalara yönelik algıları üzerine etkisini araştırmaktır. Olasılıksız uygun örneklemin kullanıldığı bu çalışmaya 60 ortaokul 6 ve 7. sınıf öğrencisi katılmış, bu öğrencilerden çalışmayı tamamlayan 48'inden toplanan veriler üzerinde istatistiksel işlemler yapılmıştır. Öğrencilerin bilimsel araştırma algıları VOSI-E ölçeği ile ölçülmüştür. Çalışma sonunda, yapılandırılmış kimya laboratuar çalışmalarının cinsiyet ve sınıf düzeylerine göre öğrencilerin sahip oldukları bilimsel araştırma algıları üzerinde bir etkisinin olmadığı anlaşılmıştır. Bilim okuryazarı bireyler yetiştirmek olan fen eğitiminde öğrencilerin bilimsel araştırma algılarının artırılmasında yapılandırılmış laboratuar çalışmalarının olumlu katkısının olmadığı, bu amaçla açık uçlu veya araştırmaya dayalı yöntemlerin daha etkin sonuçlar verebileceği önerilmektedir.
European journal of advanced chemistry research, Oct 22, 2022
I. INTRODUCTION Around 100 years ago people lived to the age of 30 on average. Improved economic ... more I. INTRODUCTION Around 100 years ago people lived to the age of 30 on average. Improved economic conditions, changes in diet and lifestyle, adjustments in work and social factors, as well as improved public health strategies and regulation of medical care, increase the average life expectancy to 71.5 years today [1]. Prolongation of life leads to common chronic diseases of older people such as cancer, cardiovascular diseases, and Alzheimer's diseases, are becoming much more prevalent. Alzheimer's disease (AD) was first defined by Dr. Alois Alzheimer in 1907 [2], [3]. Today, Alzheimer's disease (AD) is the third most expensive disease in the United States, costing society approximately $100 billion each year [4]. Although the cause of AD is still a mystery, many theories have been proposed for the causes of it [5], [6]. For example, acceleration of aging, anatomical pathways degenerations, mitochondrial and immune system dysfunctions, environmental and genetic factors, b-amyloid formation can be counted as the factors that lead to the disease [7]-[12]. Although the disease is still not curable with current clinical therapy, the treatment with glutamate receptor-selective drugs, antioxidants, inhibitors of nitric oxide synthase, calcium channel antagonists, receptor or enzyme inhibitors, and growth factors are promising approaches for slowing disease. Oxidative stress which can be defined as the imbalance between the antioxidant mechanism and the intracellular production of free radicals/reactive oxygen species (ROS), is a potential source of damage to vital molecules such as DNA, lipids, sugars, and proteins within cells. Its role in the pathogenesis and pathophysiology of cardiovascular, neurodegenerative, oncological, inflammatory, etc. diseases have been argued in the literature [13], [14]. Animal and human studies in the literature show the important role of oxidative damage occurring before symptoms occur and both b-amyloid-containing plaques and neurofibrillary tangles form in Alzheimer's disease [11], [15]. Therefore, the use of antioxidants can prevent or slow the progression of Alzheimer's disease.
Uploads
Papers by zuhal gercek