Synthesis and biological evaluation of new Mannich and Schiff bases containing 1,2,4-triazole and 1,3,4-oxadiazole nucleus

5-(Pyridine-3-yl)-1, 3, 4-oxadiazole-2-thiole 2, obtaining starting from nicotinic acid hydrazide were converted to the corresponding Mannich bases (3a–c) by the reaction with several heterocyclic amines in the presence of formaldehyde. 1,2,4-Triazole-3-thiole, (4) prepared from 1,3,4-oxadiazole-2-thiole (2) was converted to the corresponding Mannich bases (5a–e) by several steps. The synthesis of Schiff bases (6a–d) was performed from the reaction of the corresponding triazol-3-thioles with various aromatic aldehydes. The treatment of Schiff bases containing 1,2,4-triazoles 6c and 6d with morpholine or thiomorpholine generated the corresponding Mannich bases 7a, b and 8a, b. The synthesized compounds were screened for their antimicrobial, antilipase, and antiurease activities. Some of them were found to possess good-moderate antimicrobial, antiurease, and/or antilipase activity

Determination of antioxidant and antimicrobial activity of sweetgum (Liquidambar orientalis) leaf, a medicinal plant

In the study, sweetgum tree (Liquidambar orientalis), which is an endemic species that grows in Mugla, Koycegiz and is applied for medicinal purposes among the public, its leaves was examined. The antioxidant ability of the extract obtained from dried plant leaves has been evaluated using a variety of methods which are Total Phenolic Substance, Total Flavonoid, FRAP, CUPRAC, DPPH, and ABTS(+). Simultaneously, the antimicrobial activity of the plant extract was examined using disk diffusion and microdilution methods to determine the minimum inhibitor concentration (MIC). While the total phenolic content of Liquidambar orientalis extract was 96.34 mg GAE/g, the total amount of flavonoid was 2.15 mg QE/g. When the results of the antioxidant analysis were examined, it was observed that it had a good level of antioxidant activity with the results of 49.25 +/- 0.54 mmol TEAC/g according to the CUPRAC method, 39.83 +/- 0.25 mu mol Fe/g according to the FRAP method, 80.34 mu g/mL according to the DPPH method and 51.20 mu g/mL according to the ABTS(+) method. As a result of the antimicrobial analysis, it was indicated that L. orientalis extract was more effective on Staphylococcus aureus (S. aureus), which is a gram-positive bacterium and causes a wide variety of clinical diseases. Even, L. orientalis extract with an MIC value of 10 mg/mL has been found to have a higher antibacterial effect than Amoxicillin+Clavulanic acid, which is used as a standard drug in that field. This research is significant because it is the first to report the determination of all biological activities for L. orientalis, including total polyphenols, flavonoid contents, antioxidant content, and antimicrobial activity

A strategy based on the dispersive liquid-liquid microextraction of cadmium in environmental samples prior to ıts determination by flame atomic absorption spectrometry

This work has been supported by the Scientific Research Projects of Karadeniz Technical University (Project no: 1223), Turkey.A simple method was developed by combining dispersive liquid-liquid microexraction (DLLME) and flame atomic absorption spectrometry (FAAS). For the pre-concentration of trace amounts of cadmium, a new complexation chelate of 2-[(4-phenylpiperazine-5-Thioxo- 4,5-dihydro-1 ,3,4-oxadiazole-2- yl)methyl]-5-methyl-4-[2-(1H-indol e-3-yl)ethyl]-2,4-dihydro-3H-1, 2,4-Triazole-3-one (PPTOMDT) was used and mixed with the solvents of chloroform and methanol. The mixture of the extraction solutions was then directly injected into an aqueous solution containing Cd2+ ions. After centrifugation, the settled phase was diluted with 500 mu L of ethanol/nitric acid and aspirated into the FAAS. The limit of detection (LOD) was found at 0.69 mu g L-1 under optimum conditions. The relative standard deviation (RSD) for 15 replicates at a 3.75 mu g L-1 Cd2+ concentration level was 3.21%. The calibration plot was linear within the range of 2.5-15 mu g L-1 of Cd2+. After the analytical characteristics were determined, the CRM-TMDW-500 Drinking Water and CRM-SA-C Sandy Soil C, both certified reference materials, were analyzed in order to validate the method. The application of the DLLME method has been successfully tested for the determination of cadmium in solid and liquid samples. The recoveries of the spiked sample ranged between 92-96%

Türkiye’nin Artvin ve Giresun bölgelerindeki Kantaron (Hypericum montbretii ve Hypericum bupleuroides) ve Karaçalı (Paliurus spina-christi Mill) bitkilerinin antioksidan ve antimikrobiyal aktivitelerinin karşılaştırılması

Antioxidant activity 13 different samples of medicinal and aromatic plants of Centaury (Hypericum montbretii), Centaury (Hypericum bupleuroides), Blackthorn (Paliurus spina-christi Mill), including leaf, flower and stem, was investigated using DPPH, FRAP and CUPRAC methods. Total flavonoid, total phenolic amount and the antibacterial features of extracts from these herbs were also determined. According to the obtained of antioxidant datas, except for the result of total polyphenol assay, the dried leaves of Centuary (Hypericum montbretii) had the best antioxidant property that was realized in all results. Accordingly test of total polyphenol, the content of yellow flower of Centuary (Hypericum montbretii) herb was measured as of 22.48±0.66 mg GAE /g dry herb sample and so this herb had the highest total phenolic content. Antimicrobial activity tests were carried out using disc diffusion methods with 12 microbial species and the most of them displayed good-moderate antimicrobial and antifungal activity.Tıbbi ve aromatik bitkilerden olan Kantaron (Hypericum montbretii ve Hypericum bupleuroides) ve karaçalı (Paliurus spina-christi Mill) bitkilerinin yaprak, çiçek ve kök gibi kısımlarından oluşan 13 farklı örneğin antioksidan aktivitesi DPPH, FRAP ve CUPRAC yöntemleri kulanılarak incelenmiştir. Aynı zamanda bitki ekstraktların toplam fenolik ve toplam flavonoid miktarları da ölçülmüş ve antimikrobiyal özellikleri de belirlenmiştir. Antioksidan aktivite sonuçlarına göre tüm analizler içinde (toplam polifenol miktar analizi hariç) en iyi aktivite Kantaron (Hypericum montbretii) bitkisinin kuru yaprağında olduğu bulunmuştur. Toplam polifenol analizine göre ise en yüksek aktivitenin 22.485±0.656 mg GAE /g değeri ile Kantaron’un (Hypericum montbretii) çiçek kısmına ait olduğu görülmüştür. Antimikrobiyal analizler ise disk düfüzyon yöntemi kullanılarak yapılmış ve bitki ekstraktlarının 12 tane test mikrorganizması üzerine etkisi incelenmiştir. Bu sonuçlara göre bitkilerden çoğunun bakterilere ve mantar suşlarına karşı iyi derecede aktivite gösterdiği gözlenmiştir

Synthesis and antimicrobial, antiproliferative evaluation of novel quinolone and conazole analogues via conventional and microwave techniques

1,2,4-Triazole-3-one (3), acquired from cinnamaldehyde was converted to the corresponding carbox(thio)amides via several steps (6 a–c). Their reaction with sodium hydroxide gave the 1,2,4-triazole derivatives (7 a–c). Compound 3 treatment with 2-bromo-1-(4-chlorophenyl) ethanone or 2-chloro-1-(2,4-dichlorophenyl)ethanone afforded the compounds 8 a,b and by reducing these compounds reduction products were obtained (9 a,b). The synthesis of (10 a–e) was carried out by the reaction compounds 9 a,b with different benzyl chlorides. Then oxadiazole derivative (12) was obtained by ring closure from hydrazide compound 5. Subsequently compounds 3, 7 a–c, and 12 were treated with various amines in the presence of formaldehyde to yield Mannich bases (11 a–e, 14 a–e, 13 a,b). Microwave-assisted and conventional techniques were utilized for the syntheses. The structures of newly synthesized compounds were illuminated by spectroscopic methods. Their antimicrobial (MIC method), and anticancer activities (Abay's method) were examined. Results showed that most of the compounds exhibited good antimicrobial activities. Especially compounds 14 a–e which is a mannich base showed very good antitubercular activity against Mycobacterium smegmatis compared with Streptomycin standard drug. Also compounds 8 a and 9 b have been found to have strong antiproliferative effects on the HeLa cervical cancer cells and also these compounds did not have a cytotoxic effects on a normal cells

Antimicrobial and antiurease activities of newly synthesized morpholine derivatives containing an azole nucleus

2-[6-(Morpholin-4-yl)pyridin-3-ylamino]acetohydrazide (4) was obtained starting from 6-morpholin-4-ylpyridin-3-amine (2) via the formation of ester (3) and then converted to the corresponding Schiff bases (5, 6) with the reaction with aromatic aldehydes. The carbothioamide (9), obtained from the reaction of hydrazide with phenylisothiocyanate, was converted to the corresponding 1,2,4-triazole (11) and 1,3,4-thiadiazole (12) derivatives by the treatment with NaOH or H2SO4, respectively. The cyclocondenzation of 9 with 4-chlorophenacyl bromide or ethyl bromoacetate produced the corresponding 1,3-thiazole (10) or 1,3-thiazolidine derivatives (13), respectively. Antimicrobial and antiurease activities of newly synthesized compounds were investigated. Some of them were found to be active on M. smegmatis, and they displayed activity toward C. albicans and S. cerevisiae in high concentration. Compound 10 proved to be the most potent showing an enzyme inhibition activity with an IC50 = 2.37 +/- A 0.19 mu M

Chemical composition of essential oil by SPME and evaluation of antimicrobial, antioxidant activities of quercus inectoria GALL

Quercus infectoria galls have been utilized to cure widespread illnesses. In line with it, this paper aims to investigate the chemical combination of the volatile oils obtained from galls of Q. infectoria and evaluate their antioxidant and antimicrobial features. The volatiles of Q. infectoria has been isolated by solid-phase microextraction (SPME). The compositions of the volatiles were revealed via gas chromatography coupled with mass spectrometry (GC-MS). Twenty-nine substances have been characterized in the volatile essential oil of Q. infectoria. The major components of the volatile oil were (Z)-Anethol 28.55%, pentadecanolide (26.44%), diethyl phthalate (6.46%), and acetoin (5.66%). Q. infectoria showed good-moderate antimicro-bial (Staphylococcus aureus, Streptomyces griseolus, Pseudomonas citronellosis) and antifungal (Candida glabrata, Candida krusei) activities against to test microorganisms with MIC value 250 μg/mL and 125 μg/mL, respectively. Also, total flavonoid and total polyphenol amounts were found for Q. infectoria, and our to-tal polyphenol result (342.87 mg GAE/g) was found higher than the studies in the literature. At the same time Q. infectoria has been observed to have high antioxidant activity according to DPPH, FRAP, and CUPRAC assays. Especially it exhibited excellent DPPH activity for the IC50 rate of 0.002 μg/mL which is higher than the standard Trolox (IC50 = 0.008 μg/mL). This study is important because it is the first one, which reports the determination of essential oil, total polyphenol, flavonoid contents, antioxidant, and antimicrobial activities all together for Q. infectoria

Antimicrobial, antioxidant and antiproliferative activities of novel quinolones

The compound (2) formed by esterification of dimethyl morpholine (1) was converted to acetohydrazide (3). Subsequently Schiff bases (4 a-d) and carboxy(thio)amide derivatives (5 a-e) were synthesized. Then 1,2,4-triazole (6 a-e), thia(oxa)zolidine (7 c,e) and thia(oxa)zol (8 c,e) derivatives were obtained by ring closure from carboxy(thio)amides. Mannich bases, which are containing quinolone were synthesized from 1,2,4-triazoles. The structures of newly synthesized compounds were illuminated by spectroscopic methods. Their antimicrobial (MIC method), antioxidant (DPPH, FRAP, and CUPRAC methods), and anticancer activities (MTT method) were examined. Results showed that most of the compounds exhibited good antimicrobial (<0.03-31.25 mu g/mL with MIC values) and antioxidant activities (IC50=0.001-0.004 with DPPH values). Also, some of the compounds have been found to have antiproliferative effects on the prostate (PC-3), liver (Hep3B), and breast (MCF-7) human cancer cells, and also these compounds did not have a cytotoxic effect on a normal cell.This work was supported by Artvin Coruh University, BAP (2016.F11.02.06), Turkey

Determination of antioxidant and antimicrobial activities of bilberry (Vaccinium myrtillus L.) extrackts in different solvents

Bu çalışmada Giresun ilinde yetişen yaban mersininin (Vaccinium myrtillus L.) meyve ve yaprağı, hem yaş hem de kurutulmuş halinin dört farklı çözücüdeki ekstraktları (etanol, aseton, su ve dietil eter) ayrı ayrı incelenmiştir. Bitkisel ürünlerin antioksidan kapasitelerini değerlendirmek için çeşitli yöntemler kullanılmıştır. Bu yöntemler, FRAP (Fe3+ İndirgeme Antioksidan Gücü), DPPH? giderme ve toplam polifenol tayinini içermektedir. FRAP tayini yönünden, ekstraktların indirgeme güçlerinin aseton > etanol > su > dietil eter şeklinde sıralandığı görülmüştür. Serbest radikal giderme aktivitesi antioksidan sonuçlarına göre, kurutulmuş halde alınan örneklerin ekstraktları, yaş haline göre daha iyi düzeyde DPPH radikali giderme aktivitesi sergilemiştir ve en yüksek aktiviteyi çözücüsü etanol olan kuru yaprak ekstraktının gösterdiği bulunmuştur. Toplam fenolik madde miktarı tayinine göre ise, ekstraktlarda var olan fenolik madde içeriklerinin gallik asit eşdeğeri cinsinden 0.121±0.00-19.484±1.85 mg/g aralığında değiştiği ve en yüksek aktiviteyi yaban mersininin çözücüsü su olan kuru yaprak ekstraktının gösterdiği belirlenmiştir. Aynı zamanda bitki ekstrelerindeki antimikrobiyal aktivite, Agar disk difüzyon yöntemi kullanılarak tespit edilmiştir. Yaban mersini bitkisi ile hazırlanan ekstraktlar arasında, çözücüsü etanol ve aseton olan ekstrakların test mikroorganizmalarının çoğuna karşı iyi derecede aktivite gösterdiği bulunmuştur.In this study, both fresh and dried fruit, leaves extracts of bilberies (V. myrtillus L.) growed in Giresun have been investigated in four different solvents (ethanol, acetone, water and diethyl ether). Several methods have been utilized to evaluate the antioxidant capacity of plant materials. These methods include FRAP (ferric ion reducing antioxidant power), DPPH? (free radical) and analysis of total polyphenol. The reducing powers of extract have been acetone > ethanol > water > diethyl ether respectively. According to free radical scavenging activity results, the extracts obtained dried samples have had better DPPH radical scavenging results than fresh ones and the dried leaves extracts in ethanol have showed the highest activity. According to analysis of total phenol, the phenolic contents in extracts have been determined as gallic acid equivalent ranging from 0.121±0.00 to 19.484±1.85 mg/g and the dried bilberry leaves extracts in water have showed the highest activity. In addition, antimicrobial activities of plant extracts have been determined by the agar disk diffusion method. The extracts with ethanol and acetone among all bilberry extract have been showed a good degree of activity against most of tested microorganisms