1126-46-1Relevant articles and documents
Synthesis and antiviral activity of novel thioether derivatives containing 1,3,4-oxadiazole/thiadiazole and emodin moieties
Dong, Liangrun,Song, Baojing,Wu, Jian,Wu, Zengxue,Zhu, Yunying,Chen, Xuewen,Hu, Deyu
, p. 904 - 907 (2016)
A series of novel thioether derivatives containing 1,3,4-oxadiazole/thiadiazole and emodin moieties were designed and synthesized. The structures of the target compounds were confirmed by 1H NMR, 13C NMR, Infrared, and elemental analysis. The results of bioactivity analysis showed that most of the target compounds exhibited moderate to good antiviral activity against tobacco mosaic virus at a concentration of 500 mg/L. Especially, among the title compounds, Y2, Y8, and Y10 possessed appreciable curative activity in vivo, with inhibition rates of 50.51, 52.08, and 54.62%, respectively, which were similar to that of Ningnanmycin (53.40%).
Discovery of novel furo[2,3-d]pyrimidin-2-one–1,3,4-oxadiazole hybrid derivatives as dual antiviral and anticancer agents that induce apoptosis
El Mansouri, Az-eddine,Oubella, Ali,Danoun, Karim,Ahmad, Mehdi,Neyts, Johan,Jochmans, Dirk,Snoeck, Robert,Andrei, Graciela,Morjani, Hamid,Zahouily, Mohamed,Lazrek, Hassan B.
, (2021)
A new series of furo[2,3-d]pyrimidine–1,3,4-oxadiazole hybrid derivatives were synthesized via an environmentally friendly, multistep synthetic tool and a one-pot Songoashira-heterocyclization protocol using, for the first time, nanostructured palladium pyrophosphate (Na2PdP2O7) as a heterogeneous catalyst. Compounds 9a–c exhibited broad-spectrum activity with low micromolar EC50 values toward wild and mutant varicella-zoster virus (VZV) strains. Compound 9b was up to threefold more potent than the reference drug acyclovir against thymidine kinase-deficient VZV strains. Importantly, derivative 9b was not cytostatic at the maximum tested concentration (CC50 > 100 μM) and had an acceptable selectivity index value of up to 7.8. Moreover, all synthesized 1,3,4-oxadiazole hybrids were evaluated for their cytotoxic activity in four human cancer cell lines: fibrosarcoma (HT-1080), breast (MCF-7 and MDA-MB-231), and lung carcinoma (A549). Data showed that compound 8f exhibits moderate cytotoxicity, with IC50 values ranging from 13.89 to 19.43 μM. Besides, compound 8f induced apoptosis through caspase 3/7 activation, cell death independently of the mitochondrial pathway, and cell cycle arrest in the S phase for HT1080 cells and the G1/M phase for A549 cells. Finally, the molecular docking study confirmed that the anticancer activity of the synthesized compounds is mediated by the activation of caspase 3.
N-Doped Sub-3 nm Co Nanoparticles as Highly Efficient and Durable Aerobic Oxidative Coupling Catalysts
Han, Junxing,Gu, Feifei,Li, Yuchao
, p. 2594 - 2601 (2016)
A nano-coating associated with sulfuric acid leaching protocol was developed to prepare N-doped sub-3 nm Co-based nanoparticle catalyst (Co?N/C) using melamine–formaldehyde resin as the N-containing precursor, active carbon as the support, and Co(NO3)2 as the Co-containing precursor. By thermal treatment under nitrogen atmosphere at 800 °C and leached with sulfuric acid solution, a stable and highly dispersive Co?N coordination structure was uniformly dispersed on the formed Co?N/C catalyst with a Co loading of 0.47 wt % and Co nanoparticle size of 2.55 nm. The Co?N/C catalyst was characterized with XRD, XPS, Raman, SEM, TEM, ICP, and elemental analysis. The Co?N/C catalyst showed extremely high catalytic efficiency with a TON of 257 for the aerobic oxidative coupling of aldehydes with methanol to directly synthesize methyl esters with molecular oxygen as the final oxidant. The Co?N/C catalyst also showed broad substrate range and stable recyclability. After recycling for 7 times, no obvious deactivation was detected. It was confirmed that the sub-3 nm Co?N coordination structure formed between metallic Co nanoparticles and pyridinic nitrogen doping into graphitic layers functions as the active site to activate molecular oxygen for the β-H elimination from generated hemiacetal intermediates to produce methyl esters. The nano-coating associated with acid leaching protocol provides a novel strategy to prepare highly efficient non-precious metal-based catalysts.
Novel C-C bond cleavage from arylacetonitriles in alcohols to aryl carboxylic esters using potassium iodide and catalytic amount of samarium
Yu, Mingxin,Wen, Weijiang,Wang, Zhiyuan
, p. 2851 - 2857 (2006)
A novel way to cleave the carbon-carbon bond from arylacetonitriles in alcohols to their corresponding aryl carboxylic esters using potassium iodide and a catalytic amount of samarium under mild and neutral conditions is described. Useful yields of the reaction can be obtained with electron-deficient subsistent groups in aromatic rings, and the yields are higher when the subsistent group is an electron-withdrawing group (EWG) rather than an electron-donating group (EDG). Products were characterized by IR, 1H NMR, 13C NMR, and MS. Copyright Taylor & Francis Group, LLC.
Modified extra-large mesoporous silica supported Au-Ni as a highly efficient catalyst for oxidative coupling of aldehydes with methanol
Han, Junxing,Zhang, Suojiang,Zhang, Juan,Yan, Ruiyi
, p. 58769 - 58772 (2014)
Herein, we report for the first time that a La-Mg composite oxide modified extra-large mesoporous FDU-12 supported Au-Ni bimetallic catalyst exhibits excellent performance for oxidative coupling of aldehydes (including benzyl and aliphatic aldehydes) with methanol to directly produce methyl esters.
Efficient aerobic oxidation of alcohols to esters by acidified carbon nitride photocatalysts
Antonietti, Markus,Cheng, Jiajia,Lin, Sen,Savateev, Aleksandr,Wan, Qiang,Wang, Chong,Wang, Xinchen
, p. 116 - 125 (2021)
Photocatalytic aerobic oxidation of alcohols for the direct synthesis of esters has received significant attention in recent years, but the relatively low efficiency and selectivity under visible light irradiation is the main challenge for their practical applications. Here, surface acidic sites were imparted onto metal-free heterogeneous photocatalysts by the protonation of carbon nitride (HMCN) to promote the activity for the esterification reaction through further adsorption and activation of the intermediate aldehyde. The activation of the substrate could be remarkably modulated through tuning the acidic sites on the surface of the photocatalyst, leading to a controllable reactivity of the catalytic reaction. The one-pot process for the direct aerobic oxidative esterification of alcohol exhibits high efficiency and selectivity under mild and additive-free conditions and the apparent quantum yield (AQY) of the photocatalytic esterification reaction is 0.41% at 420 nm. Moreover, a scalable photocatalytic process by the merging of a continuous flow system with the heterogeneous HMCN photocatalyst is demonstrated, combining high catalytic efficiency and stability at ambient temperatures and being promising for larger-scale applications.
Design, synthesis, in silico molecular docking and biological evaluation of novel oxadiazole based thiazolidine-2,4-diones bis-heterocycles as PPAR-γ agonists
Nazreen, Syed,Alam, Mohammad Sarwar,Hamid, Hinna,Yar, Mohammad Shahar,Shafi, Syed,Dhulap, Abhijeet,Alam, Perwez,Pasha,Bano, Sameena,Alam, Mohammad Mahboob,Haider, Saqlain,Ali, Yakub,Kharbanda, Chetna,Pillai
, p. 175 - 185 (2014)
A library of novel 1,3,4-oxadiazole and 2-4-thiazolidinedione based bis-heterocycles 7 (a-r) has been synthesized which exhibited significant PPAR-?3 transactivation and blood glucose lowering effect comparable with the standard drugs Pioglitazone and Rosiglitazone. Compounds 7m and 7r did not cause body weight gain and were found to be free from hepatotoxic and cardiotoxic side effects. Compounds 7m and 7r increased PPAR-?3 gene expression by 2.10 and 2.00 folds, respectively in comparison to the standard drugs Pioglitazone (1.5 fold) and Rosiglitazone (1.0 fold). Therefore the compounds 7m and 7r may be considered as potential candidates for development of new antidiabetic agents.
Natural formation of chlorobenzoic acids (CBA) and distinction between PCB-degraded CBA
Niedan,Schoeler
, p. 1233 - 1241 (1997)
Mono- and dichlorobenzoic acid (CBA) could be found in samples of remote bog pond water and sediment. The 2,4-CBA always had the highest concentrations. In bog water samples the concentrations ranged between 0.11 and 0.48 μg/l. Besides 2,4-CBA most only 2,5-CBA could be found as dichlorobenzoic acid. In all samples we could detect also trichloroacetic acid (TCAA). The TCAA concentrations correlate with the CBA concentrations. As TCAA is known as a naturally produced organohalogen, this correlation can be seen as an indication to a natural formation of CBA. A confirmation of this presumption is our detection CBA in a reaction of benzoic acid with the chlorinating enzyme chloroperoxidase (CPO).
Facile Coupling of Aldehydes with Alcohols: An Evolved Tishchenko Process for the Preparation of Unsymmetrical Esters
Liu, Heng,Eisen, Moris S.
, p. 4852 - 4858 (2017)
A facile coupling process between aldehydes and alcohols to afford unsymmetrical esters is presented herein. This transformation is complementary to the Tishchenko reaction and provides access to unsymmetrical esters under very mild conditions. Various aldehydes and alcohols are suitable in this reaction, and the addition of a sacrificial trifluoromethyl ketone allows the process to take place in a highly selective manner. A plausible mechanism based on details obtained by monitoring the reaction progress and deuterium-labeling studies has been proposed.
Polymer supported Zn-salen complexes: An effective one-pot oxidative esterification of aldehydes to carboxylic esters
Balinge, Kamlesh Rudreshwar,Khiratkar, Avinash Ganesh,Bhagat, Pundlik Rambhau
, p. 1085 - 1095 (2017)
Polymer-supported Zn-salen (PS-Zn-salen) complexes were synthesized, characterized and used as a catalyst for one-pot oxidative esterification of aldehydes with alcohols. The PS-Zn-salen heterogeneous catalyst exhibited a high-performance for the oxidative esterification of aldehydes to the corresponding methyl/ethyl esters using hydrogen peroxide as a green oxidant. Due to the synergistic effect of polymer support, the heterogeneous catalyst presented superior catalytic activity and afford 100% conversion of 3,4,5-trimethoxybenzaldehyde and 4-chlorobenzaldehyde to corresponding esters under optimized conditions. The different alcohol substrates study (viz. methyl alcohol, ethyl alcohol, allyl alcohol and benzyl alcohol) showed reasonable selectivity for esters, indicating the scope of the catalysts. Significantly, the synthesized complexes possess good hydrophobic/heterogeneous properties, which permit facile reclamation of the catalyst by using mere filtration. Moreover, the effect of counter anions of complex also studied which indicated that there is no appreciable influence on the conversion of product. The catalyst was reused up to 5th successive run with the average conversion of ester 87.4%. Mechanistic studies have recognized that this “one pot” direct oxidative esterification proceeds through acid formation, proven by a GC–MS. The catalyst is also found to be very stable, up to 280?°C, confirmed by the thermo gravimetric study.
