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In this study, the effects of electron-withdrawing or electron-releasing groups in methyl benzoate esters, which are widely used in the fragrance industry, on the antioxidant and antibacterial activities of the compounds were investigated. Firstly, methyl benzoates with electron-withdrawing (NO2 and Cl groups) or electron-donating groups (CH3 and OCH3 groups) in the para position, which are commercial compounds, were synthesized, and extensively studied in terms of reaction conditions, and spectral data in their instrumental analysis methods. Then, the synthesized compounds were evaluated for their antioxidant, antibacterial, and cytotoxic activities. Among them, methyl 4-nitrobenzoate exhibited the highest inhibition against Staphylococcus aureus and Pseudomonas aeruginosa. Methyl 4-methoxybenzoate was selected for cytotoxicity evaluation due to its high antioxidant activity, and while the results indicated a dose-dependent decrease in cell viability, lower concentrations may still be considered for cosmetic applications. These findings suggest that antioxidant activity and cytotoxic activity are directly related to the electron density of the molecule. Therefore, this very up-to-date research covers many implications for organic chemistry, medicinal chemistry, biotechnology, and microbiology. Therefore, the results obtained may have great potential to be applied in the cosmetic industry and could be used as exceptionally useful information on alternative raw material selection for researchers in the fragrance industry. These results also suggest that methyl benzoates have potential as lead compounds for the development of novel antioxidant, antibacterial, and cytotoxic agents, but further studies are needed to fully explore their applications in various fields.

© 2023 Wiley Periodicals LLC.In this study, we have synthesized a series of 3-(pyridin-2-yl)-2-(pyridin-2-ylimino)thiazolidin-4-ol derivatives regioselectively from 2-iminothiazolidin-4-ones using LiAlH4 at room temperature. Due to the presence of the restricted rotation around the N3-Caryl single bond, the formation of M/P isomers was observed. The OH group of the hemiaminal was found to orient itself on the same side with pyridyl nitrogen during this restricted rotation to form an intramolecular hydrogen bond, which was demonstrated by the computational DFT study. This orientation presumably inhibited the occurrence of dehydration and stabilized the molecule.

Today, usage of NSAIDs (nonsteroidal anti-inflammatory drugs) is very common. However, it has been proven by many studies that NSAIDs with free carboxylic acid group damage the GI (gastrointestinal) system. Our aim was to mask the acidic groups of NSAIDs to prevent or reduce their side effects while preserving their pharmacological effects. In this study, new amide derivatives of known NSAIDs, compounds 11–20, were synthesized to investigate their analgesic and anti-inflammatory effects using in vivo models. While compound 11 showed the most remarkable anti-inflammatory activity by 60.9% inhibition value at 200 mg/kg dose, compounds 11, 12, 15 and 18 had almost the same analgesic activity to that of acetylsalicylic acid (100 mg/kg) and flurbiprofen (100 mg/kg). In addition, all test compounds used at high dose (200 mg/kg, p.o) did not show any acute toxicity. COX-1 and COX-2 inhibition properties of all compounds were measured by biochemical methods and the interaction of the most active compounds with COX enzymes is elucidated by computer-assisted virtual screening methods. It was determined by in vitro enzyme inhibition studies that compound 11 and 13, synthesized from selective COX-1 inhibitors dexketoprofen and flurbiprofen, are selective COX-2 inhibitors. Moreover, compounds 11–13 were found to be non-mutagenic according to the mutagenicity assay using Salmonella TA98 and TA100 strains with and without metabolic activation. Finally, the prediction of ADMET profile and drug-likeness properties of compounds 11–20 were examined and the obtained results were evaluated.

Bu çalışmada, aspir tohumlarından farklı yöntemlerle yağ ekstrakte edilmiş ve ekstrakte edilen aspir tohumu yağı (ATY) transesterifikasyon prosesi ile biyodizele (B100)’e sentezlenmiştir. B100, dizel yakıt (DF) ve farklı ağır alkoller (AA)’ler belli oranlarda harmanlanarak elde edilen yakıtların motor performansı, emisyonları ve yanma parametreleri incelenmiştir. Yanma parametrelerinin deneysel sonuçları yapay sinir ağları (YSA) ile tahmin edilmiştir. Ekstraksiyon yöntemleri arasında maksimum yağ elde etme verimliliği sokslet ekstraksiyon yöntemi ile %32.49 olarak gerçekleşmiştir. ATY’nin yağ asidi bileşimleri sırasıyla %30.9 ve %56.4 civarında C18:1 ve C18:2’dir. ATY’nin biyodizele sentezlenmesinde alkol/yağ molar oranı 4.799/1 olarak hesaplanmıştır. Biyodizelin sentezi spektroskopik yöntemler ile doğrulanmıştır. 1H NMR ile yağ asidi metil esterlere (YAME)’lere dönüşüm %95.23 olarak hesaplanmıştır. Gerçekleştirilen analizler neticesinde sentezlenen biyodizelin ASTM-D6751 ve EN-14214 standartlarını karşıladığı görülmüştür. Testlerde DF50DE50 yakıtı DF’den sonra en düşük fren özgül yakıt tüketimi (FÖYT) ve fren özgül enerji tüketimi (FÖET) ile sonuçlanmışken fren termal verimliliği (FTV) bakımından ise DF’den sonra en yüksek olan yakıttır. DF50HE50 yakıtı ile en yüksek egzoz gazı sıcaklığı (EGS) elde edilmişken, en düşük EGS ise DF50B25HE25 yakıtı ile elde edilmiştir. B100’ün üretmiş olduğu NOx emisyonu DF’ye göre yüksektir. Düşük NOx emisyonu ise dekanolün olduğu karışımlar tarafından üretilmiştir. B100’ün üretmiş olduğu CO emisyonu DF’nin üretmiş olduğundan daha yüksektir. DF50B50’nin üretmiş olduğu CO emisyonları tekli ve ikili yakıt karışımlarının üretmiş olduklarına kıyasla daha düşüktür. DF’nin üretmiş olduğu is emisyonu ise bütün test yakıtlarının üretmiş olduğundan daha yüksektir. DF50OC50 artan yükler ile yüksek silindir basınçları (SB)’ler oluştururken, en büyük SB DF50HE50 yakıtınındır. DF50HE50 yakıtının net ısı salımı hızı (NISH) en yüksektir. B100’ün basınç artış oranı (BAO), DF yakıtından yüksek iken DF50B50 yakıtının BAO’sı tekli yakıtlarınkine göre daha düşük olmuştur. Üçlü yakıt karışımlarının BAO’sı ikili yakıt karışımlarına göre düşüktür. Yanma verilerinin YSA ile tahmini ortalama kare hatası (MSE) değerleri doğrultusunda oldukça başarılı olduğu görülmüştür., In this study, oil was extracted from safflower seeds (SSs) using different methods, and the extracted SSO was synthesized into B100 through the transesterification process. The performance, emissions, and combustion parameters of fuels obtained by blending B100, DF, and different heavy alcohols (HA) in specific proportions were investigated. The experimental results of combustion parameters were predicted using ANNs. Among the extraction methods, the soxhlet extraction method achieved a maximum oil extraction efficiency of 32.49%. The FA compositions of SSO are approximately 30.9% and 56.4% for C18:1 and C18:2, respectively. The alcohol/oil molar ratio for the synthesis of SSO biodiesel was calculated as 4.799/1. The synthesis of biodiesel was confirmed using spectroscopic methods. The conversion of fatty acids to FAMEs was determined to be 95.23% using 1H NMR spectroscopy. Based on the conducted analyses, the synthesized biodiesel was found to meet the ASTM-D6751 and EN-14214 standards. In the tests, the fuel blend DF50DE50 resulted in the lowest brake-specific fuel consumption (BSFC) and brake-specific energy consumption (BSEC) compared to DF, while it exhibited the highest brake thermal efficiency (BTE) among the fuels tested. The fuel blend DF50HE50 achieved the highest exhaust gas temperature (EGT), while the lowest EGT was obtained with the fuel blend DF50B25HE25. The NOx emissions produced by B100 are higher compared to DF. Low NOx emissions were produced by mixtures containing decanol. The CO emissions produced by B100 are higher compared to those generated by DF. The CO emissions produced by DF50B50 are lower compared to those generated by single and dual fuel blends. The particulate matter (PM) emissions produced by DF are higher compared to those generated by all tested fuels. DF50OC50 generates high cylinder pressures (CP) with increasing loads, while the highest CP is achieved with the DF50HE50 fuel blend. The net heat release rate (NHRR) of the DF50HE50 fuel blend is the highest. The pressure rise rate (PRR) of B100 is higher than that of DF, while the PRR of the DF50B50 fuel blend is lower compared to single fuels. It has been observed that the prediction of combustion data using ANNs is highly successful, as indicated by the low MSE values.

Glukosa merupakan senyawa organik golongan monosakarida yang menjadi salah satu sumber nutrisi penting dan diperlukan tubuh sebagai sumber energi. Glukosa dapat ditemukan dalam buah-buahan maupun jus buah yang saat ini digemari masyarakat. Kadar glukosa dalam jus buah sangat penting diketahui nilainya terkait dengan jumlah konsumsi yang dibutuhkan oleh tubuh. Namun untuk mengetahui kadar kandungan glukosa dibutuhkan waktu yang lama dan biasanya merusak sampel. Dalam penelitian ini, dilakukan pendugaan kadar kandungan glukosa jus buah menggunakan Spektroskopi Inframerah Dekat (Near Infrared Spectroscopy, NIRS) dengan perhitungan Regresi Kuadrat Terkecil Parsial (Partial Least Square Regression, PLSR) menggunakan teknik validasi Leave One Out dalam membuat model kalibrasi. Sampel data kalibrasi yang digunakan sebanyak 14 buah dan sampel data validasi sebanyak 10 jus buah. Spektrum yang diperoleh NIRS dianalisis pada daerah bilangan gelombang 4200-4800 cm-1. Pra-perlakuan data meliputi smoothing, normalisasi, turunan pertama, dan turunan kedua diterapkan kedalam data spektrum untuk mendapatkan hasil prediksi yang presisi. Penggunaan NIRS dan teknik PLSR dapat memprediksi kadar kandungan glukosa cukup baik, dengan nilai RMSE 3 mg/dL pada data kalibrasi dan dapat mengetahui kadar glukosa jus buah. Kadar glukosa tertinggi terdapat pada tebu 713 mg/dL dan terendah pada air kelapa 247 mg/dL.

The goal of this research is to develop a spectrofluorometric method for analyzing carvedilol in pharmaceutical preparations and apply this method to the formulations. The method’s calibration curve was plotted between 25 and 500 ng/mL. The mean calibration equation from six replicate experiments is y=1.8736x+7.7291. The correlation coefficient value was higher than 0.997 for the mean calibration curve. The trueness results were better than 2.09% and the precision results were less than 2.73% for carvedilol. The detection and quantitation limits were determined as 2.196 and 6.654 ng/mL, respectively. In addition, the method was used to study carvedilol in pharmaceutical preparations. The method had recovery values >98.4% for all samples in pharmaceutical preparations. The detection wavelength was optimized to maximize the sensitivity of the method. This method has good sensitivity with satisfactory results. Therefore, the method can be used in carvedilol analysis.

Medicinal plants have been used throughout history in the treatment of many diseases in traditional Anatolian folk medicine as well as all over the world. The rapid increase in agricultural and industrial activities due to the increasing population around the world causes air, water and soil pollution, and accumulation of potentially toxic elements in medicinal plants. In this study, plant mineral nutrients and potentially toxic elements analyzes were carried out in 38 plant species belonging to the medicinally important families Asteraceae, Fabaceae and Lamiaceae. The percentage of macroelements (in %) varies between 0.20 and 1.46 for calcium, 0.08 and 1.35 for potassium, 0.04 and 0.24 for magnesium, 0.01 and 0.34 for sodium, while concentrations of microelements and potentially toxic elements (in mg kg−1) vary between 3.21 and 721.28 for aluminum, 41.33 and 231.01 for boron, 0.01 and 0.61 for cadmium, 1.09 and 47.79 for chromium, 12.90 and 43.13 for copper, 17.75 and 1109.39 for iron, 51.50 and 715.48 for manganese, 0.12 and 9.42 for nickel, 1.58 and 22.11 for lead and finally 80.82 and 260.08 for zinc. In addition, estimated daily intake (EDI), target hazard quotient (THQ), and hazard index (HI) for potentially toxic elements, and Recommended Dietary Allowance (RDA) values for mineral nutrients were calculated. In some samples in industrial and mining areas, accumulation of some potentially toxic elements was slightly above the permissible limits set by the World Health Organization (WHO). In Summary, the importance of collecting medicinal plants from protected areas such as mountainous rural areas, far from mining, close to clean rivers, and regular control of values with potentially toxic elements analyzes for human health has been understood once again.

Thiazolyl-hydrazones (THs) exhibit a wide spectrum of biological activity that can be enhanced by complexation with various metal ions. Zn(II) complexes with α-pyridine-1, 3-TH ligands may represent an alternative to the standard platinum- based chemotherapeutics. In addition, they show photoluminescence properties and thus can be regarded as multifunctional materials. In this study, we synthesized and characterized three neutral Zn(II) complexes (1–3) with pyridine-based TH ligands HLS1‒3 in order to investigate the influence of the ligands charge on the structure and intermolecular interactions in the solid state, and consequently photophysical properties. The deprotonation of the ligands mainly affects the relative energies of electronic levels in the complexes, compared to cationic counterparts, resulting in similar photoluminescence mechanisms and quantum yields with a small shift in emission energy. The influence of the substitution at the ligands’ periphery on the selected quantum molecular descriptors of the complexes is localized to the substitution site. Also, the substituents did not considerably influence the redox responses of the complexes. However, predominant spectral changes were observed in the course of the first reduction and oxidation processes which caused distinct spectral color changes indicating their possible functionality for electrochromic applications. In addition, complex 1 showed antiproliferative activity with GI50 values below 2 µM on all tested cancer cell lines.

Glukosa merupakan senyawa organik golongan monosakarida yang menjadi salah satu sumber nutrisi penting dan diperlukan tubuh sebagai sumber energi. Glukosa dapat ditemukan dalam buah-buahan maupun jus buah yang saat ini digemari masyarakat. Kadar glukosa dalam jus buah sangat penting diketahui nilainya terkait dengan jumlah konsumsi yang dibutuhkan oleh tubuh. Namun untuk mengetahui kadar kandungan glukosa dibutuhkan waktu yang lama dan biasanya merusak sampel. Dalam penelitian ini, dilakukan pendugaan kadar kandungan glukosa jus buah menggunakan Spektroskopi Inframerah Dekat (Near Infrared Spectroscopy, NIRS) dengan perhitungan Regresi Kuadrat Terkecil Parsial (Partial Least Square Regression, PLSR) menggunakan teknik validasi Leave One Out dalam membuat model kalibrasi. Sampel data kalibrasi yang digunakan sebanyak 14 buah dan sampel data validasi sebanyak 10 jus buah. Spektrum yang diperoleh NIRS dianalisis pada daerah bilangan gelombang 4200-4800 cm-1. Pra-perlakuan data meliputi smoothing, normalisasi, turunan pertama, dan turunan kedua diterapkan kedalam data spektrum untuk mendapatkan hasil prediksi yang presisi. Penggunaan NIRS dan teknik PLSR dapat memprediksi kadar kandungan glukosa cukup baik, dengan nilai RMSE 3 mg/dL pada data kalibrasi dan dapat mengetahui kadar glukosa jus buah. Kadar glukosa tertinggi terdapat pada tebu 713 mg/dL dan terendah pada air kelapa 247 mg/dL.

Bu çalışmada, spektroskopik ve kromatografik tekniklerden yararlanılarak kişisel bakım ürünlerinde ağır metal ve polietilen glikol (PEG) mikroplastiğinin kalitatif ve kantitatif tayini gerçekleştirilmiştir. Ticari olarak temin edilebilen on dört farklı markanın kişisel bakım ürünü, öncelikle açık sistem yaş yakma işlemine tabii tutulmuş ardından elektrotermal atomik absorpsiyon spektrofotometresi (ET AAS) ile bakır (Cu) ve alevli atomik absorpsiyon spektrofotometresi (A AAS) ile lityum (Li) analizleri yapılmıştır. Bakır ve lityum için tespit sınırı (LOD) sırasıyla 0,02 µg/L ve 0,03 mg/L olarak hesaplanmıştır. Tayin sınırları ise (LOQ) bakır için 0,06 µg/L ve lityum için 0,09 mg/L olarak hesaplanmıştır. ET AAS ile yapılan analizlerde bakır düzeyleri 0,21 – 0,65 µg/g aralığındadır. A AAS ile yapılan lityum analizlerinde tüm numuneler için sonuçların tayin sınırının altında (

© 2022 Elsevier Inc.The connection of Epstein Barr virus (EBV) with diseases such as Burkitt Lymphoma, Hodgkin disease, multiple sclerosis, systemic lupus erythematosus and various B-cell lymphomas made EBV glycoproteins one of the most popular vaccine immunogens. As a protein being encoded by EBV, the viral membrane envelope protein gp350 is studied extensively due to its abundancy on the surface and its interaction with complementary receptor, CR2. The binding of CR2 and gp350 not only leads to the entrance of the virus to the B-cells, but also prevents CR2 and C3d protein interactions that are required for immune response. Thus, understanding the inhibition of gp350 activity is crucial for vaccine development. Although, the active residues on gp350 structure were determined by several mutational studies, the exact mechanism of CR2 binding is still not clear. To this end, we have performed molecular docking followed by molecular dynamics simulations and MM-PBSA on wildtype and several mutated gp350 and CR2 structures. Apart from identifying crucial amino acids, the results of per-residue decomposition energy analysis clarified the individual energy contributions of amino acids and were also found to be accurate in differentiating the active site residues in CR2 binding. Here, we highlight the role of binding region residues (linker-1) but more interestingly, the dynamic relation between the distant sites of gp350 (linker-2 and D3 residues) and CR2. These findings can lead further vaccine development strategies by pointing to the importance of computationally found novel regions that can be potentially used to modulate gp350 activity.

(E)-1-(4-Methoxyanthracen-1-yl)-2-phenyldiazene or C_21 H_16 N_2 O is one of the tautomer azo dyes which is the most usable compound in several industries as a sensing molecule, nowadays. As we know, more than 90% of the existing commercial azo dyes are tautomeric ones (Kelemen, 1981). Quantum chemistry calculations can clarify the relationship between structures and electrochemical properties of molecular compounds for future applications. A comparison of the experimental and theoretical calculations can be very useful in making correct assignments and understanding the relationship between molecular structures and their properties. In this study, the main purpose is to characterize the structural geometries of the title molecule ((E)-1-(4-Methoxyanthracen-1-yl)-2-phenyldiazene), spectroscopic and electronic properties by utilizing ab-initio method based on density functional theory (DFT) (Becke, 1988; Becke, 1993). The molecular geometry and vibrational spectroscopy of the title molecule, in the ground state, have been computed by applying DFT/B3LYP method with the basis set of 6-311G (d,p). The structural properties, such as bond length, bond angle, and dihedral angle, are in excellent agreement with those of available experiment data (Crochet et al., 2011). 114 vibrational modes of the title molecule have been specified with stretching, in-plane-bending, out-of-plane-bending, and torsion vibrations. UV absorption spectra within dimethyl sulfoxide (DMSO) solvent have been predicted by using the time-dependent density functional theory (TD-DFT) (Ronca et al., 2014). Moreover, 1H and 13C NMR chemical shifts have been computed in DMSO solvent by using the Gauge-Invariant Atomic Orbital (GIAO) approach within DFT/B3LYP method (Scott and Radon, 1996; Wolinskiet et al., 1997). Finally, the electronic properties of the title molecule have been also attained by using Koopman’s theorem enable to determine the Lowest Unoccupied Molecular Orbital - Highest Occupied Molecular Orbital (HOMO-LUMO) interaction (Sastri and Perumareddi, 1997; Pearson, 1986). It can be reported that this molecule has gap energy (Eg) bigger than 1.5 eV which indicates thermodynamically stable and durable, low ionization potential energy (IP) which tends to be reducing agents because it is easily losing its electron, about 2.43 eV electron affinity (EA) which denotes that it has good conductive properties, high electronegativity (x) which shows that the title molecule is a polar character, low value of chemical hardness (ƞ) and global electrophilicity index., (E)-1-(4-Methoxyanthracen-1-yl)-2-phenoldiazene veya C_21 H_16 N_2 O, günümüzde birçok endüstride bir algılayıcı molekül olarak en çok kullanılan bileşik olan tautomer azo boyalarından biridir. Bildiğimiz gibi, mevcut ticari azo boyaların %90'dan fazlası totomerik boyalardır (Kelemen, 1981). Kuantum kimyası hesaplamaları, gelecekteki uygulamalar için moleküler bileşiklerin yapıları ve elektrokimyasal özellikleri arasındaki ilişkiyi netleştirebilir. Deneysel ve teorik hesaplamaların karşılaştırılması, doğru atamaların yapılmasında ve moleküler yapılar ile özellikleri arasındaki ilişkinin anlaşılmasında çok faydalı olabilir. Bu çalışmada temel amaç, başlık molekülünün ((E)-1-(4-Methoxyanthracen-1-yl)-2-phenyldiazene) yapısal geometrilerinin, ab-initio yöntemi kullanılarak spektroskopik ve elektronik özelliklerinin karakterize edilmesidir. yoğunluk fonksiyonel teorisi (DFT) üzerine (Becke, 1988; Becke, 1993). Temel durumdaki başlık molekülünün moleküler geometrisi ve titreşim spektroskopisi, 6-311G (d,p) temel seti ile DFT/B3LYP yöntemi uygulanarak hesaplanmıştır. Bağ uzunluğu, bağ açısı ve dihedral açı gibi yapısal özellikler, mevcut deney verileriyle mükemmel bir uyum içindedir (Crochet ve diğerleri, 2011). Başlık molekülünün 114 titreşim modu, germe, düzlem içi bükülme, düzlem dışı bükülme ve burulma titreşimleri ile belirtilmiştir. Dimetil sülfoksit (DMSO) çözücü içindeki UV absorpsiyon spektrumları, zamana bağlı yoğunluk fonksiyonel teorisi (TD-DFT) kullanılarak tahmin edilmiştir (Ronca ve diğerleri, 2014). Ayrıca, DFT/B3LYP yöntemi dahilinde Gauge-Invariant Atomic Orbital (GIAO) yaklaşımı kullanılarak DMSO solventinde 1H ve 13C NMR kimyasal kaymaları hesaplanmıştır (Scott ve Radon, 1996; Wolinskiet ve diğerleri, 1997). Son olarak, başlık molekülünün elektronik özellikleri, En Düşük Boş Moleküler Orbital - En Yüksek Dolu Moleküler Orbital (HOMO-LUMO) etkileşimini belirlemeyi sağlayan Koopman teoremi kullanılarak da elde edilmiştir (Sastri ve Perumareddi, 1997; Pearson, 1986). Bu molekülün, termodinamik olarak kararlı ve dayanıklı, düşük iyonizasyon potansiyel enerjisine (IP) işaret eden 1.5 eV'den büyük boşluk enerjisine (Örn) sahip olduğu, elektronunu kolayca kaybettiği için indirgeyici ajan olma eğiliminde olduğu, yaklaşık 2.43 eV elektron afinitesi olduğu bildirilebilir. (EA), iyi iletken özelliklere, başlık molekülünün polar bir karakter olduğunu gösteren yüksek elektronegatifliğe (x), düşük kimyasal sertlik değerine (ƞ) ve global elektrofiliklik indeksine sahip olduğunu belirtir.

u çalışmada temel amacımız, kuantum kimyası hesaplama yöntemini kullanarak C15H12N2O2 başlık molekülünü karakterize etmektir. Moleküllerin, iyonların veya çekirdeklerin, yapısal parametrelerinin ve bazı spektroskopik, elektronik ve termal özelliklerinin elde edilmesini sağlayan nicelleştirilmiş enerji seviyelerini belirlemek için ab-initio simülasyonları gerçekleştirdik. Bileşik, Gaussian 09W alt programında uygulanan 6-31G(d,p) temel seti ile yoğunluk fonksiyonel teorisi (DFT)/B3LYP'ye dayalı ab-initio yöntemi kullanılarak optimize edilmiştir. Hesaplanan bağ uzunluğu, bağ açısı ve dihedral açının geometrik parametreleri, mevcut deneyinkilerle iyi bir uyum içindedir. Optimize edilmiş yapı kullanılarak başlık bileşiğinin titreşim spektrumları için aynı temel set ve hesaplama yöntemi kullanılmıştır. Molekülün titreşim frekanslarının işaretlenmesi VEDA4 programı (Vibrational Energy Distribution Analysis) ile yapılmıştır. Başlık molekülü 31 atoma ve en çok bükülme titreşimine sahip 87 temel titreşim moduna sahiptir. Deneysel kimyasal kaymalar genellikle DMSO (Dimetil Sülfoksit) ve Asetonitril çözeltilerinde elde edildiğinden, molekülün aynı çözeltilerdeki 1H ve 13C NMR kimyasal kaymaları DFT/B3LYP yöntemi uygulanarak Gauge-Bağımsız Atomik Yörünge (GIAO) yaklaşımı kullanılarak hesaplanmıştır. 6-31G (d,p) temel seti ile. Ayrıca, çalışılan molekülün UV-Vis spektral analizi hem DMSO hem de Asetonitril çözücülerde araştırılmıştır. Bileşiğin maksimum absorpsiyon zirveleri, Zamana Bağlı Kendinden Tutarlı Alan (TD-SCF)/DFT/B3LYP/6-31G(d,p) yöntemi ile değerlendirilmiştir. Her iki çözücüde de 257 nm'de herhangi bir omuz olmaksızın tek bir absorbans gözlenmiştir. Son olarak, kimyasal sertlik/yumuşaklık, iyonlaşma potansiyeli, en yüksek dolu moleküler orbital (HOMO)-en düşük boş moleküler orbital (LUMO) enerji seviyeleri, elektronegatiflik ve enerji bant aralığı gibi elektronik özellikler tahmin edilmiştir. DFT hesaplamalarından elde ettiğimiz sonuçlar, yalnızca mevcut deneysel verilerin yorumlanmasına yardımcı olmakla kalmaz, aynı zamanda başlık molekülünün spektroskopik ve elektronik özelliklerini ayrıntılı olarak aydınlatır., In this study, our main aim to characterize the title molecule of C15H12N2O2 by using quantum chemistry computational method. We have performed ab-initio simulations to determine the quantized energy levels of molecules, ions or nuclei, which enable to obtain its structural parameters and, some spectroscopic, electronic and thermal properties. The compound is optimized by using ab-initio method based on the density functional theory (DFT)/B3LYP with 6-31G(d,p) basis set implemented in Gaussian 09W subprogram. The geometric parameters of bond length, bond angle and dihedral angle computed are in good agreement with those of available experiment. The same basis set and computational method have been utilized for the vibrational spectra of the title compound by using the optimized structure. The marking of the vibrational frequencies of the molecule have been carried out via the VEDA4 program (Vibrational Energy Distribution Analysis). The title molecule has 31 atoms and 87 fundamental vibrational modes, with the most bending vibrations. Since experimental chemical shifts are generally obtained in DMSO (Dimethyl Sulfoxide) and Acetonitrile solutions, the 1H and 13C NMR chemical shifts of the molecule in the same solutions are computed by using the Gauge-Independent Atomic Orbital (GIAO) approach applying DFT/B3LYP method with the basis set of 6-31G (d,p). Moreover, UV-Vis spectral analysis of the studied molecule have been investigated in both of the DMSO and Acetonitrile solvents. The maximum absorption peaks of compound have been evaluated by the Time Dependent Self-Consistent Field (TD-SCF)/DFT/B3LYP/6-31G(d,p) method. A single absorbance without any shoulder at 257 nm in both solvent have been observed. At last, electronic properties such as chemical hardness/softness, ionization potential, highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy levels, electronegativity and energy bandgap have been predicted. Our results from DFT calculations not only aid in the interpretation of available experimental data, but also illuminate the spectroscopic and electronic properties of the title molecule in detail.

In this study, a new double-armed crown ether ligand (L) was synthesized by interacting 4',5'-bis(bromomethyl)benzo-15-crown-5 and 2-iodo-3-hydroxypyridine. Synthesized ligand (L) was reacted with sodium picrate and potassium picrate to obtain a Na+ and K+ complex. In this way, a 1:1 (filling) complex (NaL) with Na+ conforming to the cavity size of benzo-15-crown-5 and a 1:2 (sandwich) complex (KL2) with K+ larger than the cavity size were obtained. In addition, transition metal complex (AgL) was synthesized from the reaction of compound L with silver nitrate. The structure of the obtained ligands and complexes were characterized using spectroscopic methods (FTIR, HRMS, 1H-NMR, 13C-NMR). Finally, the thermal properties of the synthesized ligand and complexes were investigated using TGA - DTA methods and the results were observed compatible with the structures of the compounds., Bu çalışmada 4′,5′-bis(bromometil)benzo-15-crown-5 ile 2-iyodo-3-hidroksipiridin etkileştirilerek, yeni, çift kollu taç eter ligandı (L) sentezlenmiştir. Sentezlenen ligand (L), Na+ ve K+ kompleksi elde etmek üzere sodyum pikrat ve potasyum pikrat ile tepkimeye sokulmuştur. Böylelikle, benzo-15-crown-5’in halka boşluğuna uygun olan Na+ ile 1:1 (filling) kompleksi (NaL) ve halka boşluğundan daha büyük olan K+ ile 1:2 (sandviç) kompleksi (KL2) elde edilmiştir. Ayrıca bileşik L’nin gümüş nitrat ile reaksiyonu sonucunda geçiş metal kompleksi (AgL) sentezlenmiştir. Elde edilen ligand ve komplekslerin yapısı, spektroskopik yöntemler (FTIR, HRMS, 1H-NMR, 13C-NMR) kullanılarak aydınlatılmıştır. Son olarak, sentezlenen ligand ve komplekslerin termal özellikleri TGA - DTA yöntemleri kullanılarak incelenmiş ve bileşik yapıları ile uyumlu sonuçlar elde edilmiştir.

Since the obtained chiral alcohols are rather useful as well as biologically active compounds, reduction of ketones to their respective alcohols is a crucial topic in synthetic chemistry. Thus, a new phosphinite ligand was synthesized by the interaction of cationic species N-vinyl imidazolium (1) with PCy2Cl. This phosphinite ligand in combination with [Ru(η6-p-cymene)(µ-Cl)Cl]2 and Ir(η5-C5Me5)(μ-Cl)Cl]2 gave active catalytic systems for transfer hydrogenation reaction. Under optimum circumstances, ruthenium complex (3) showed rather high conversion reduction reaction of acetophenone. Reversibility of the transfer hydrogenation reaction was found to be low under these reaction circumstances.

In applied spectroscopy, the purpose of multivariate calibration is almost exclusively to relate analyte concentrations and spectroscopic measurements. The multivariate calibration model provides estimates of analyte concentrations based on the spectroscopic measurements. Predictive performance is often evaluated based on a mean squared error. While this average measure can be used in model selection, it is not satisfactory for evaluating the uncertainty of individual predictions. For a calibration, the uncertainties are sample specific. This is especially true for multivariate calibration, where interfering compounds may be present. Consider in-line spectroscopic measurements during a chemical reaction, production, etc. Here, reference values are not necessarily available. Hence, one should know the uncertainty of a given prediction in order to use that prediction for telling the state of the chemical reaction, adjusting the process, etc. In this paper, we discuss the influence of variance and bias on sample-specific prediction errors in multivariate calibration. We compare theoretical formulae with results obtained on experimental data. The results point towards the fact that bias contribution cannot necessarily be neglected when assessing sample-specific prediction ability in practice.

Bor elementini içeren kimyasal bileşiklerin gün geçtikçe artan önemi ile özgün çalışmalara yer verilmiştir. Bu amaçla ilk olarak metoksipolietilen glikol amin ve 4-formilfenilboronik asit reaksiyonu ile polimer grupları içeren yeni bir boronik asit ve boronat esterleri sentezlendi. Daha sonra yeni boronik asit içeren polimer grubunun çeşitli diollerle dehidrasyon reaksiyonu sonucunda polimer grupları içeren boronat esterleri elde edilmiştir. Ortaya çıkan yeni bor katkılı polimerlerin yapısı başarıyla sentezlendi. Bu polimerlerin yapıları NMR (1H, 13C ve 11B), LC-MS/MS spektrometresi, IR, UV-Vis absorbans spektroskopisi ve floresan spektroskopisi ile aydınlatıldı., With the increasing importance of chemical compounds containing the boron element day by day, original studies have been included. For this aim, a new boronic acid and boronate esters containing polymer groups were synthesized by the reaction methoxypolyethylene glycol amine and 4-formylphenylboronic acid for the firstly. Then, as a result of the dehydration reaction of the new boronic acid containing polymer groups with various diols, the boronate esters containing polymer groups were obtained. The structure of the resulting new boron-doped polymers was successfully synthesized. The structures of these polymers were elucidated by NMR (1H, 13C and 11B), LC-MS/MS spectrometer, IR, UV-Vis absorbance spectroscopy and fluorescence spectroscopy.

© 2022 Taylor & Francis Group, LLC.A simple, rapid, and precise high performance liquid chromatography (HPLC) method was developed to determine the flavonoid apigenin in cosmetic products containing chamomile extracts. A C18 column was used as stationary phase and 70:30 ethanol:water was used as mobile phase with a 1 mL/min flow rate and isocratic elution. The temperature was stabilized at 25 °C during the separation. The injection volume was 50 μL. The apigenin peak was eluted at 4.15 ± 0.4 min. The method was validated according to International Conference on Harmonisation (ICH) criteria in terms of linearity, limit of detection, limit of quantitation, selectivity, sensitivity, robustness, accuracy, and precision. The limits of detection and quantitation were 0.060 and 0.2 μg/mL respectively. The linear range was from 0.2 to 20 μg/mL. The relative standard deviation values for intraday and interday analyses were less than 1.64%. The developed procedure was applied to the analysis of various cosmetic products. It is expected that the method is suitable for routine analysis, quality control and standardization of cosmetic products for apigenin.