- Combination of a new chiroptical probe and theoretical calculations for chirality detection of primary amines
-
A method to determine absolute configurations of primary amines by combined use of a chiroptical probe 1 and theoretical calculations is reported. Probe 1 is linked to chiral primary amines yielding 1-amine conjugates, which exhibited exciton coupled circular dichroism in the m-quaterphenyl chromophores. The ratios between the P and M conformers of the 1-amine conjugates, which are calculated with DFT, were correlated highly with the sign and amplitude of the observed CD spectra.
- Kuwahara, Shunsuke,Nakamura, Masaya,Yamaguchi, Akira,Ikeda, Mari,Habata, Yoichi
-
-
Read Online
- Design, synthesis and characterization of π-conjugated 2,5-diphenylsubstituted-1,3,4-oxadiazole-based D-π-A-π’-D′ form of efficient deep blue functional materials: Photophysical properties and fluorescence “Turn-off” chemsensors approach
-
This paper primarily deals with the design and synthesis of three novel conjugated organic molecules containing 1,3,4-oxadiazole unit (abbreviated as CHEM-6(a-c)) with Donor-π-Acceptor-π’-Donor’ structures by utilizing palladium catalyzed Suzuki cross coupling reaction. Molecular structures of these compounds were characterized by using various spectroscopic and analytical techniques namely 1H NMR, 13C NMR, FT-IR, GC–MS and elemental analysis. Optical properties of these compounds have been investigated by using UV–visible absorption and fluorescence spectroscopy. Also, the PL investigations on solid state samples (as thin films) were carried out. Furthermore, solvatochromism and Density Functional Theory (DFT) computations are studied in detail. The experimentally measured optical band gap (Egopt) values of compounds CHEM-6a, CHEM-6b and CHEM-6c were determined to be 3.11, 3.03 and 2.70 eV, respectively. The DSC and TGA results revealed that the compounds exhibit good thermal stabilities. Current results indicate that the compounds CHEM-6(a-c) are promising candidates and could play an important role in the field of optoelectronic devices and possibly find potential applications in development of OLEDs. In addition, the compounds CHEM-6(a-c) showed an interesting property of chemical sensing for Hg(II) ion which can be clearly observed by naked eyes from the changes in solution color and fluorescence (under UV excitation).
- Najare, Mahesh S.,Patil, Mallikarjun K.,Garbhagudi, Manjunatha,Yaseen, Mohammed,Inamdar, Sanjeev R.,Khazi, Imtiyaz Ahmed M.
-
-
Read Online
- Novel cycloaddition of 2-alkyl-3-benzoyl-2-thianaphthalenes
-
Deprotonation of 2-alkyl-3-benzoyl-2-thiochromenium salts 1 or 2 with 2 equiv. of triethylamine in ethanol affords the unexpected benzothiopyran derivatives 3 and 4; the structure of 3a is confirmed by X-ray crystallography.
- Shimizu, Hiroshi,Yonezawa, Takenori,Watanabe, Tomoko,Kobayashi, Kazuhiro
-
-
Read Online
- Using m icrowave and ultrasound to synthesis of substituted bis-acyl hydrazone derivatives
-
In this paper, some new bis-acyl hydrazone derivatives (4a-f) were prepared through the reaction of carboxylic acid hydrazides with 1,4-diacetylbenzene using classical methods, microwave and ultrasound irradiation methods. These compounds are obtained through a series of reactions where some carboxylic acids react with ethanol first in the presence of concentrated sulfuric acid to give the corresponding esters (2a-f), which when treatment with aqueous hydrazine give carboxylic acid hydrazides (3a-f).thus, The results proved that the use of microwave and ultrasound techniques is much better than the classical methods, as it gave a higher yield, shorter reaction time, and the absence of the use of solvents. All newly synthesized compounds were confirmed by IR, (1H & 13C) NMR spectral analysis and the corresponding reactions were monitored by TLC using the reported eluent.
- Mohammed, Salim J.,Sheat, Attallah M.,A.abood, Salih,Yahya, Omar M.
-
p. 6423 - 6427
(2021/11/01)
-
- Schiff Base Functionalized 1,2,4-Triazole and Pyrene Derivative for Selective and Sensitive Detection of Cu2+?ion?in the Mixed Organic- Aqueous Media
-
We have prepared Schiff base functionalized 1,2,4-triazole and pyrene derivative for selective, sensitive, and naked eye colorimetric detection of Cu2+ in the mixed organic- aqueous media. Amongst the 18 different metal ions studied for absorption and fluorescence titration, only Cu2+ ion encourages the modification in spectral properties of Schiff base functionalized 1,2,4-Triazole and Pyrene Probe. The stoichiometric ratio of the TP-Cu2+ complex was determined to be 2:1 according to Job’s plot. The lower detection limit estimated for Cu2+ is 0.234?nM which shows excellent sensitivity and selectivity of the present analytical method towards detection of Cu2+ ion in the mixed organic-aqueous media. The present approach has been successfully utilized for the quantitative determination of Cu2+ ion from environmental aqueous solution.
- Choi, Nam Gyu,Vanjare, Balasaheb D.,Mahajan, Prasad G.,Nagarajan, Rajendran,Ryoo, Hyang Im,Lee, Ki Hwan
-
p. 1739 - 1749
(2021/09/03)
-
- Design, synthesis, in vitro and in vivo evaluation against MRSA and molecular docking studies of novel pleuromutilin derivatives bearing 1, 3, 4-oxadiazole linker
-
A class of pleuromutilin derivatives containing 1, 3, 4-oxadiazole were designed and synthesized as potential antibacterial agents against Methicillin-resistant staphylococcus aureus (MRSA). The ultrasound-assisted reaction was proposed as a green chemistry method to synthesize 1, 3, 4-oxadiazole derivatives (intermediates 85–110). Among these pleuromutilin derivatives, compound 133 was found to be the strongest antibacterial derivative against MRSA (MIC = 0.125 μg/mL). Furthermore, the result of the time-kill curves displayed that compound 133 could inhibit the growth of MRSA in vitro quickly (- 4.36 log10 CFU/mL reduction). Then, compound 133 (- 1.82 log10 CFU/mL) displayed superior in vivo antibacterial efficacy than tiamulin (- 0.82 log10 CFU/mL) in reducing MRSA load in mice thigh model. Besides, compound 133 exhibited low cytotoxicity to RAW 264.7 cells. Molecular docking studies revealed that compound 133 was successfully localized in the binding pocket of 50S ribosomal subunit (ΔGb = -10.50 kcal/mol). The results indicated that these pleuromutilin derivatives containing 1, 3, 4-oxadiazole might be further developed into novel antibiotics against MRSA.
- Liu, Jie,Zhang, Guang-Yu,Zhang, Zhe,Li, Bo,Chai, Fei,Wang, Qi,Zhou, Zi-Dan,Xu, Ling-Ling,Wang, Shou-Kai,Jin, Zhen,Tang, You-Zhi
-
-
- Synthesis and biological evaluation of honokiol derivatives bearing 3-((5-phenyl-1,3,4-oxadiazol-2-yl)methyl)oxazol-2(3h)-ones as potential viral entry inhibitors against sars-cov-2
-
The 2019 coronavirus disease (COVID-19) caused by SARS-CoV-2 virus infection has posed a serious danger to global health and the economy. However, SARS-CoV-2 medications that are specific and effective are still being developed. Honokiol is a bioactive component from Magnoliae officinalis Cortex with damp-drying effect. To develop new potent antiviral molecules, a series of novel honokiol analogues were synthesized by introducing various 3-((5-phenyl-1,3,4-oxadiazol-2-yl)methyl)oxazol-2(3H)-ones to its molecule. In a SARS-CoV-2 pseudovirus model, all honokiol derivatives were examined for their antiviral entry activities. As a result, 6a and 6p demonstrated antiviral entry effect with IC50 values of 29.23 and 9.82 μM, respectively. However, the parental honokiol had a very weak antiviral activity with an IC50 value more than 50 μM. A biolayer interfero-metry (BLI) binding assay and molecular docking study revealed that 6p binds to human ACE2 protein with higher binding affinity and lower binding energy than the parental honokiol. A competitive ELISA assay confirmed the inhibitory effect of 6p on SARS-CoV-2 spike RBD’s binding with ACE2. Importantly, 6a and 6p (TC50 > 100 μM) also had higher biological safety for host cells than honokiol (TC50 of 48.23 μM). This research may contribute to the discovery of potential viral entrance inhibitors for the SARS-CoV-2 virus, although 6p’s antiviral efficacy needs to be validated on SARS-CoV-2 viral strains in a biosafety level 3 facility.
- Bai, Li-Ping,Guo, Yong,Jiang, Zhi-Hong,Liu, Jia-Zheng,Meng, Jie-Ru,Xu, Ting,Zheng, Zhi-Yuan
-
-
- Development of Novel (+)-Nootkatone Thioethers Containing 1,3,4-Oxadiazole/Thiadiazole Moieties as Insecticide Candidates against Three Species of Insect Pests
-
To improve the insecticidal activity of (+)-nootkatone, a series of 42 (+)-nootkatone thioethers containing 1,3,4-oxadiazole/thiadiazole moieties were prepared to evaluate their insecticidal activities against Mythimna separata Walker, Myzus persicae Sulzer, and Plutella xylostella Linnaeus. Insecticidal evaluation revealed that most of the title derivatives exhibited more potent insecticidal activities than the precursor (+)-nootkatone after the introduction of 1,3,4-oxadiazole/thiadiazole on (+)-nootkatone. Among all of the (+)-nootkatone derivatives, compound 8c (1 mg/mL) exhibited the best growth inhibitory (GI) activity against M. separata with a final corrected mortality rate (CMR) of 71.4%, which was 1.54- and 1.43-fold that of (+)-nootkatone and toosendanin, respectively; 8c also displayed the most potent aphicidal activity against M. persicae with an LD50 value of 0.030 μg/larvae, which was closer to that of the commercial insecticidal etoxazole (0.026 μg/larvae); and 8s showed the best larvicidal activity against P. xylostella with an LC50 value of 0.27 mg/mL, which was 3.37-fold that of toosendanin and slightly higher than that of etoxazole (0.28 mg/mL). Furthermore, the control efficacy of 8s against P. xylostella in the pot experiments under greenhouse conditions was better than that of etoxazole. Structure-activity relationships (SARs) revealed that in most cases, the introduction of 1,3,4-oxadiazole/thiadiazole containing halophenyl groups at the C-13 position of (+)-nootkatone could obtain more active derivatives against M. separata, M. persicae, and P. xylostella than those containing other groups. In addition, toxicity assays indicated that these (+)-nootkatone derivatives had good selectivity to insects over nontarget organisms (normal mammalian NRK-52E cells and C. idella and N. denticulata fries) with relatively low toxicity. Therefore, the above results indicate that these (+)-nootkatone derivatives could be further explored as new lead compounds for the development of potential eco-friendly pesticides.
- Cheng, Wanqing,Fan, Jiangping,Guo, Yong,Han, Meiyue,Ma, Nannan,Yan, Xiaoting,Yang, Ruige
-
p. 15544 - 15553
(2022/01/03)
-
- Vitamin B1-catalyzed aerobic oxidative esterification of aromatic aldehydes with alcohols
-
A straightforward aerobic oxidative esterification of aryl aldehydes with alcohols has been developed for the synthesis of substituted esters by employing vitamin B1 as a cost-effective, metal-free, and eco-friendly NHC catalyst. Air is used as a green terminal oxidant. The reaction is a useful addition to the existing NHC-catalytic oxidative esterification.
- Chu, Xue-Qiang,Ge, Danhua,Luo, Xin-Long,Xu, Pei,Yu, Zi-Lun
-
supporting information
p. 30937 - 30942
(2021/11/19)
-
- Design, Synthesis, and Study of the Insecticidal Activity of Novel Steroidal 1,3,4-Oxadiazoles
-
A series of novel steroidal derivatives with a substituted 1,3,4-oxadiazole structure was designed and synthesized, and the target compounds were evaluated for their insecticidal activity against five aphid species. Most of the tested compounds exhibited potent insecticidal activity against Eriosoma lanigerum (Hausmann), Myzus persicae, and Aphis citricola. Compounds 20g and 24g displayed the highest activity against E. lanigerum, showing LC50 values of 27.6 and 30.4 μg/mL, respectively. Ultrastructural changes in the midgut cells of E. lanigerum were detected by transmission electron microscopy, indicating that these steroidal oxazole derivatives might exert their insecticidal activity by destroying the mitochondria and nuclear membranes in insect midgut cells. Furthermore, a field trial showed that compound 20g exhibited effects similar to those of the positive controls chlorpyrifos and thiamethoxam against E. lanigerum, reaching a control rate of 89.5% at a dose of 200 μg/mL after 21 days. We also investigated the hydrolysis and metabolism of the target compounds in E. lanigerum by assaying the activities of three insecticide-detoxifying enzymes. Compound 20g at 50 μg/mL exhibited inhibitory action on carboxylesterase similar to the known inhibitor triphenyl phosphate. The above results demonstrate the potential of these steroidal oxazole derivatives to be developed as novel pesticides.
- Bai, Hangyu,Jiang, Weiqi,Li, Qi,Li, Tian,Ma, Shichuang,Shi, Baojun,Wu, Wenjun
-
p. 11572 - 11581
(2021/10/12)
-
- Copper-mediated simple and direct aerobic oxidative esterification of arylacetonitriles with alcohols/phenols
-
A simple and direct aerobic oxidative esterification reaction of arylacetonitriles with alcohols/phenols is achieved in the presence of a copper salt and molecular oxygen, which produces a broad range of aryl carboxylic acid esters in good to high yields. Copper salt plays multiple roles in the transformation, which allows the oxygenation of C-H bond, cleavage of inert C-C bond, and formation of C-O bond in one pot without the assistance of any of the acids, bases, ligands, and so on. The reaction provides a simple, direct, and efficient protocol towards functionalized esters, especially aryl benzoates, from readily available starting materials.
- Dong, Jianyu,Chen, Xiuling,Ji, Fangyan,Liu, Lixin,Su, Lebin,Mo, Min,Tang, Jian-Sheng,Zhou, Yongbo
-
-
- Pleuromutilin derivative with 1, 3, 4-oxadiazole side chain and preparation and application thereof
-
The invention belongs to the field of medicinal chemistry, and particularly relates to a pleuromutilin derivative with a 1, 3, 4-oxadiazole side chain and preparation and application thereof The pleuromutilin derivative with the 1, 3, 4-oxadiazole side chain is a compound shown in a formula 2 or a pharmaceutically acceptable salt thereof, and a solvent compound, an enantiomer, a diastereoisomer and a tautomer of the compound shown in the formula 2 or the pharmaceutically acceptable salt thereof or a mixture of the solvent compound, the enantiomer, the diastereoisomer and the tautomer in any proportion, including a racemic mixture. The pleuromutilin derivative has good antibacterial activity, is especially suitable for being used as a novel antibacterial agent for systemic system infection of animals or human beings, and has good water solubility.
- -
-
Paragraph 0055-0056; 0070; 0090; 0092; 0095; 0103
(2021/07/24)
-
- Oxazole ring-containing honokiol thioether derivative and preparation method and application thereof
-
The invention discloses an oxazole ring-containing honokiol thioether derivative, a preparation method thereof and application of the oxazole ring-containing honokiol thioether derivative as an alpha-glucosidase inhibitor, the chemical structure of the oxazole ring-containing honokiol thioether derivative is shown as a general formula (I), and R is selected from non-substituted or substituted phenyl. Compared with the prior art, the invention provides the novel honokiol thioether derivative containing the oxazole ring, and the honokiol thioether derivative containing the oxazole ring has good inhibitory activity on alpha-glucosidase, provides more possibilities for treating diabetes, and is expected to be used for preparing novel candidate drug molecules for treating diabetes. In addition, the preparation process is simple, the cost is low, and the yield is high.
- -
-
Paragraph 0042-0044
(2021/08/11)
-
- Preclinical evaluation of 1,2,4-triazole-based compounds targeting voltage-gated sodium channels (VGSCs) as promising anticonvulsant drug candidates
-
Epilepsy is a chronic neurological disorder affecting nearly 65–70 million people worldwide. Despite the observed advances in the development of new antiepileptic drugs (AEDs), still about 30–40% of patients cannot achieve a satisfactory seizure control. In our current research, we aimed at using the combined results of radioligand binding experiments, PAMPA-BBB assay and animal experimentations in order to design a group of compounds that exhibit broad spectrum of anticonvulsant activity. The synthesized 4-alkyl-5-substituted-1,2,4-triazole-3-thione derivatives were primarily screened in the maximal electroshock-induced seizure (MES) test in mice. Next, the most promising compounds (17, 22) were investigated in 6 Hz (32 mA) psychomotor seizure model. Protective effect of compound 22 was almost similar to that of levetiracetam. Moreover, these compounds did not induce genotoxic and hemolytic changes in human cells as well as they were characterized by low cellular toxicity. Taking into account the structural requirements for good anticonvulsant activity of 4-alkyl-5-aryl-1,2,4-triazole-3-thiones, it is visible that small electron-withdrawing substituents attached to phenyl ring have beneficial effects both on affinity towards VGSCs and protective activity in the animal models of epilepsy.
- Kaproń, Barbara,?uszczki, Jarogniew J.,Siwek, Agata,Karcz, Tadeusz,Nowak, Gabriel,Zagaja, Miros?aw,Andres-Mach, Marta,Stasi?owicz, Anna,Cielecka-Piontek, Judyta,Kocki, Janusz,Plech, Tomasz
-
-
- Oxidative Esterification of Aldehydes and Alcohols Catalyzed by Camphor-Based Imidazolium Salts
-
Abstract: Sixteen new camphor-based imidazolium salts have been synthesized with renewable camphorsulfonic acid as the starting material. The chemical shifts of the characteristic proton of C2 on the imidazolium ring (N?C=N) were discussed thoroughly and all of these imidazolium salts exhibit good thermal stability. Furthermore, the excellent catalytic performance of the synthesized imidazolium salts were observed in the oxidative esterification between aromatic or aliphatic aldehydes containing electron-withdrawing or electron-donating groups on aromatic ring and primary or secondary alcohol by air as the sole oxidant. Graphic Abstract: [Figure not available: see fulltext.].
- Bian, Tiancen,Feng, Li,Li, Danfeng,Huang, Jiaxin,Zhao, Yuxun,Xu, Xu,Yang, Yiqin,Wang, Shifa
-
p. 1812 - 1820
(2020/01/11)
-
- Construction of Esters through Sulfuryl Fluoride (SO 2 F 2) Mediated Dehydrative Coupling of Carboxylic Acids with Alcohols at Room Temperature
-
A facile method for the construction of esters through dehydrative coupling of carboxylic acids with alcohols is developed. The reactions are mediated by sulfuryl fluoride (SO 2 F 2) at room temperature and proceed with high efficiency. The method has several advantages including broad substrate scope, mild conditions, excellent functional group compatibility and affords high yields, even on gram scale.
- Qin, Hua-Li,S Alharbi, Njud,Wang, Shi-Meng
-
p. 3901 - 3907
(2019/10/11)
-
- Preparation method and application of 4-formaldehyde oxime ethyl benzoate
-
The invention provides a preparation method of 4-formaldehyde oxime ethyl benzoate. The preparation method comprises the following steps: S1, dissolving 4-bromobenzoic acid in ethanol, and then addingan acyl chloride reagent for reaction to obtain yellow 4-ethyl bromobenzoate; S2, dissolving the 4-ethyl bromobenzoate in an amide solvent, and then adding a cyanation reagent for reaction to obtain4-ethyl cyanobenzoate; S3, dissolving the 4-ethyl cyanobenzoate with an alcohol reagent, and then adding hydroxylamine hydrochloride, alkali and water for reaction, and performing concentration underreduced pressure to obatin a solid of the 4-formaldehyde oxime ethyl benzoate. The preparation method solves the problems of long process route, cumbersome operation, harsh reaction conditions, high preparation cost, high production safety risk, troublesome posttreatment and the like in an original process. The synthetic process route of the preparation method disclosed by the invention is short;the reaction conditions are mild; the operation is simple; the raw materials required for the reaction are cheap and easy to obtain; the solvent used can be recycled; the production cost is lower; thepreparation method is suitable for large-scale industrial production.
- -
-
Paragraph 0016; 0017
(2019/07/04)
-
- Synthesis and bioactivity of sulfide derivatives containing 1,3,4-oxadiazole and pyridine
-
A series of novel sulfide derivatives containing 1,3,4-oxadiazole and pyridine were synthesized, characterized, and tested for their antibacterial activity against tobacco bacterial wilt and rice bacterial blight and for insecticidal activity toward diamondback moth. The results showed that some compounds had good insecticidal and bactericidal activity, e.g., the activities of compounds 6e and 6g–6j toward tobacco bacterial wilt were much better than those of commercial thiodiazole-copper, and some of the synthesized compounds possessed good insecticidal activity against Plutella xylostella. Compounds 6d, 6h, 6j, 6l, 6p, 6r, and 6p displayed over 93% activity at 500 mg L? 1.
- Yu, Gang,Chen, Shunhong,He, Feng,Luo, Dexia,Zhang, Yu,Wu, Jian
-
p. 1075 - 1085
(2019/09/10)
-
- Design and synthesis of new norfloxacin-1,3,4-oxadiazole hybrids as antibacterial agents against methicillin-resistant Staphylococcus aureus (MRSA)
-
Toward the search of new antibacterial agents to control methicillin-resistant Staphylococcus aureus (MRSA), a class of new norfloxacin-1,3,4-oxadiazole hybrids were designed and synthesized. Antibacterial activities against drug-sensitive bacteria S. aureus and clinical drug resistant isolates of MRSA were evaluated. Compound 5k exhibited excellent antibacterial activities against S. aureus (MIC: 2 μg/mL) and MRSA1–3 (MIC: 0.25–1 μg/mL). The time-kill kinetics demonstrated that compound 5k had an advantage over commonly used antibiotics vancomycin in killing S. aureus and MRSA. Moreover, compound 5k could inhibit the bacteria and destroy their membranes in a short time, and showed very low cytotoxicity to NRK-52E cells. Some interesting structure-activity relationships (SARs) were also discussed. These results indicated that these norfloxacin-1,3,4-oxadiazole hybrids could be further developed into new antibacterial agents against MRSA.
- Guo, Yong,Xu, Ting,Bao, Chongnan,Liu, Zhiyan,Fan, Jiangping,Yang, Ruige,Qin, Shangshang
-
-
- Camphoryl imidazole type ionic liquid and preparation method and application thereof
-
The invention discloses a camphoryl imidazole type ionic liquid and a preparation method and application thereof. According to the preparation method, a derivative camphorsulfonic acid of a natural renewable resource camphor is taken as a raw material to prepare 10-iodocamphor; then the 10-iodocamphor and aryl imidazole are subjected to a quaterisation reaction to prepare camphoryl imidazole iodide; then the camphoryl imidazole iodide and sodium hexafluorophosphate, sodium tetrafluoroborate, bis(trifluorosulfonimide)lithium and the like are subjected to ion exchange to prepare camphoryl imidazole hexafluorophosphate, camphoryl imidazole tetrafluoroborate, camphoryl imidazole bis(trifluorosulfonimide)salt and other ionic liquids. The camphoryl imidazole type ionic liquid shows good catalytic activity for an oxidation esterification reaction of aldehyde-alcohol, has the advantages of short reaction time, good reaction selectivity and high product yield, and has a good application prospect.
- -
-
Paragraph 0060; 0067
(2019/10/05)
-
- Design, synthesis, insecticidal activity and 3D-QSR study for novel trifluoromethyl pyridine derivatives containing an 1,3,4-oxadiazole moiety
-
A series of trifluoromethyl pyridine derivatives containing 1,3,4-oxadiazole moiety was designed, synthesized and bio-assayed for their insecticidal activity. The result of bio-assays indicated the synthesized compounds exhibited good insecticidal activity against Mythimna separata and Plutella xylostella, most of the title compounds show 100% insecticidal activity at 500 mg L-1 and >80% activity at 250 mg L-1 against the two pests. Compounds E18 and E27 showed LC50 values of 38.5 and 30.8 mg L-1 against Mythimna separata, respectively, which were close to that of avermectin (29.6 mg L-1); compounds E5, E6, E9, E10, E15, E25, E26, and E27 showed 100% activity at 250 mg L-1, which were better than chlorpyrifos (87%). CoMFA and CoMSIA models with good predictability were proposed, which revealed the electron-withdrawing groups with an appropriate bulk at 2- and 4-positions of benzene ring could enhance insecticidal activity.
- Xu,Wang,Luo,Yu,Guo,Fu,Zhao,Wu
-
p. 6306 - 6314
(2018/02/19)
-
- A general electrochemical strategy for the Sandmeyer reaction
-
Herein we report a general electrochemical strategy for the Sandmeyer reaction. Using electricity as the driving force, this protocol employs a simple and inexpensive halogen source, such as NBS, CBrCl3, CH2I2, CCl4, LiCl and NaBr for the halogenation of aryl diazonium salts. In addition, we found that these electrochemical reactions could be performed using anilines as the starting material in a one-pot fashion. Furthermore, the practicality of this process was demonstrated in the multigram scale synthesis of aryl halides using highly inexpensive graphite as the electrode. A series of detailed mechanism studies have been performed, including radical clock and radical scavenger study, cyclic voltammetry analysis and in situ electron paramagnetic resonance (EPR) analysis.
- Liu, Qianyi,Sun, Beiqi,Liu, Zheng,Kao, Yi,Dong, Bo-Wei,Jiang, Shang-Da,Li, Feng,Liu, Guoquan,Yang, Yang,Mo, Fanyang
-
p. 8731 - 8737
(2018/12/10)
-
- Formation of esters and amides via metal-free Csp2-Csp3 bond cleavage of α-nitro ketone: Mechanistic insight to the reaction pathway
-
A catalyst free protocol for hucleophilic Csp2-Csp3 bond cleavage of a-nitroketone has been achieved for the formation of C-O and C-N bond. A series of differently substituted a-nitroketones could be selectively cleaved and converted into corresponding esters and tosylamides in presence of alcohols and bromamine-T respectively. Mechanism of the C-C bond cleavage has been proposed by identifying different reaction intermediates using IR and NMR spectroscopic methods.
- Sarma, Manas Jyoti,Phukan, Prodeep
-
p. 523 - 533
(2019/05/21)
-
- Broadly Applicable Ytterbium-Catalyzed Esterification, Hydrolysis, and Amidation of Imides
-
An efficient, broadly applicable, operationally simple, and divergent process for the transformation of imides into a range of carboxylic acid derivatives under mild conditions is reported. By simply using catalytic amounts of ytterbium(III) triflate as a Lewis acid promoter in the presence of alcohols, water, amines, or N,O-dimethylhydroxylamine, a broad range of imides is smoothly and readily converted to the corresponding esters, carboxylic acids, amides, and Weinreb amides in good yields. This method notably enables an easy cleavage of oxazolidinone-based auxiliaries.
- Guissart, Céline,Barros, Andre,Rosa Barata, Luis,Evano, Gwilherm
-
supporting information
p. 5098 - 5102
(2018/09/13)
-
- Unprecedented alkylation of carboxylic acids by boron trifluoride etherate
-
The alkylation of carboxylic acids by an ethyl moiety of boron trifluoride etherate in the absence of ethyl alcohol from the reaction system is unexpected and novel. Both aromatic and aliphatic carboxylic acids were clearly alkylated affording good yields in short reaction times with the exception of nicotinic acid that necessitated an overnight reaction. It was noted that while ortho-substituted hydroxyl groups of carboxylic acids investigated were not affected by alkylation, those of meta- and para-substituted carboxylic acids were partially etherified. Furthermore, the alkylation reaction was found to be compatible with a range of functional groups such as halogens, amino and nitro groups except for the alkene function of undecylenic acid that underwent polymerisation with concomitant alkylation of its carboxylic acid function.
- Jumbam, Ndze D.,Maganga, Yamkela,Masamba, Wayiza,Mbunye, Nomthandazo I.,Mgoqi, Esethu,Mtwa, Sphumusa
-
p. 387 - 392
(2018/09/06)
-
- Fe-catalyzed esterification of amides via C-N bond activation
-
An efficient Fe-catalyzed esterification of primary, secondary, and tertiary amides with various alcohols for the preparation of esters was performed. The esterification process was accomplished with FeCl3$6H2O, which is a stable, inexpensive, environmentally friendly catalyst with high functional group tolerance.
- Chen, Xiuling,Hu, Siying,Chen, Rongxing,Wang, Jian,Wu, Minghu,Guo, Haibin,Sun, Shaofa
-
p. 4571 - 4576
(2018/02/09)
-
- Chemoselective and Metal-Free Synthesis of Aryl Esters from the Corresponding Benzylic Alcohols in Aqueous Medium Using TBHP/TBAI as an Efficient Catalytic System
-
A novel and transition-metal-free strategy has been developed for the synthesis of aryl esters starting from corresponding benzylic primary alcohols as the exclusive substrates using tert -butyl hydroperoxide (TBHP) as a terminal oxidant in the presence of catalytic amount of tetrabutylammonium iodide (TBAI) and imidazole, where the aliphatic alcohols remained unaffected. These reactions are highly chemoselective and associated with high yield and wide applicability accommodating a wide range of substituents. Excellent chemoselectivity has also been demonstrated through intramolecular competition experiments. This protocol can be considered as an important analogue of Tishchenko reaction using benzylic alcohols as the substrates instead of benzaldehydes.
- Nandy, Sneha,Ghatak, Avishek,Das, Asit Kumar,Bhar, Sanjay
-
p. 2208 - 2212
(2018/10/02)
-
- Development of N-Doped Carbon-Supported Cobalt/Copper Bimetallic Nanoparticle Catalysts for Aerobic Oxidative Esterifications Based on Polymer Incarceration Methods
-
Heterogeneous nitrogen-doped carbon-incarcerated cobalt/copper bimetallic nanoparticle (NP) catalysts, prepared from nitrogen-containing polymers, were developed, and an efficient catalytic process for aerobic oxidative esterification was achieved in the presence of a low loading (1 mol %) of catalyst that could be reused and easily reactivated. This protocol enabled diverse conditions for the bimetallic NP formation step to be screened, and significant rate acceleration by inclusion of a copper dopant was discovered. The catalytic activity of the bimetallic Co/Cu catalysts is much higher than that for cobalt catalysts reported to date and is even comparable with noble-metal NP catalysts.
- Yasukawa, Tomohiro,Yang, Xi,Kobayashi, Shu
-
supporting information
p. 5172 - 5176
(2018/09/12)
-
- Smectic liquid crystals comprising triazole banana shaped achiral molecules: Synthesis and characterization
-
A series of novel liquid crystals containing [1,2,3]-triazole ring were synthesized via “click chemistry.” Their mesomorphic properties and photoelectric properties were investigated and the results indicated that most of compounds exhibited SmA over a wide temperature range (about 50°C). The threshold voltage and the response time of the mixture, T4 and LC 50100 were shorten 0.43?V and 71.5?ms with respect to those of LC 50100 respectively.
- Li, Xiaolian,Zhang, Zongying,Liuya
-
p. 395 - 404
(2017/05/26)
-
- Graphene Oxide: An Efficient Acid Catalyst for the Construction of Esters from Acids and Alcohols
-
Graphene oxide was found to be an efficient and reusable acid catalyst for the esterification reaction. A wide range of aliphatic and aromatic acids and alcohols were compatible with the standard conditions and afforded the corresponding products in good yields. The heterogeneous catalyst can be easily recovered and recycled in dichloro-ethane solvent with good catalytic activity.
- Chen, Zhengwang,Wen, Yuelu,Fu, Yejuan,Chen, Hai,Ye, Min,Luo, Guotian
-
supporting information
p. 981 - 985
(2017/05/05)
-
- Design, synthesis, biological evaluation, and 3D-QSAR analysis of podophyllotoxin–dioxazole combination as tubulin targeting anticancer agents
-
The advancement of cancer-fighting drugs has never been a simple linear process. Those drug design professionals begin to find inspiration from the nature after failing to find the ideal products by creative drug design and high-throughput screening. To obtain new molecules for inhibiting tubulin, podophyllotoxin was adopted as the leading compound and 1,3,4-oxadiazole was brought in to the C-4 site of podophyllotoxin in this research. A series of seventeen podophyllotoxin-derived esters have been achieved and then evaluated their antitumor activities against four different cancer cell lines: A549, MCF-7, HepG2, and HeLa. Among all the compounds, compound 7c showed the best antiproliferating properties with IC50?=?2.54?±?0.82?μm against MCF-7 cancer cell line. It was obvious that the content of ROS grew significantly in MCF-7 in a way depending on the dosage. The time- and dose-dependent cell cycle assays revealed that compound 7c could apparently block cell cycle in the phase of G2/M along with the upregulation of cyclin A2 and CDK2 protein. According to further studies, confocal microscopy experiment has certified that compound 7c could restrain cancer from growing by blocking the polymerization of microtubule. Meanwhile, compound 7c could be ideally integrated with the colchicine site of tubulin. In future, it would be feasible to selectively design tubulin inhibitors with the help of 3D-QSAR. This means that it is hopeful to develop compound 7c as a potential agent against cancer due to its biological characteristics.
- Wang, Zi-Zhen,Sun, Wen-Xue,Wang, Xue,Zhang, Ya-Han,Qiu, Han-Yue,Qi, Jin-Liang,Pang, Yan-Jun,Lu, Gui-Hua,Wang, Xiao-Ming,Yu, Fu-Gen,Yang, Yong-Hua
-
p. 236 - 243
(2017/07/13)
-
- Design and optimization of N-acylhydrazone pyrimidine derivatives as E. coli PDHc E1 inhibitors: Structure-activity relationship analysis, biological evaluation and molecular docking study
-
By targeting the thiamin diphosphate (ThDP) binding site of Escherichia coli (E. coli) pyruvate dehydrogenase multienzyme complex E1 (PDHc E1), a series of novel ‘open-chain’ classes of ThDP analogs A, B, and C with N-acylhydrazone moieties was designed and synthesized to explore their activities against E. coli PHDc E1 in vitro and their inhibitory activity against microbial diseases were further evaluated in vivo. As a result, A1–23 exhibited moderate to potent inhibitory activities against E. coli PDHc E1 (IC50 = 0.15–23.55 μM). The potent inhibitors A13, A14, A15, C2, had strong inhibitory activities with IC50 values of 0.60, 0.15, 0.39 and 0.34 μM against E. coli PDHc E1 and with good enzyme-selective inhibition between microorganisms and mammals. Especially, the most powerful inhibitor A14 could 99.37% control Xanthimonas oryzae pv. Oryzae. Furthermore, the binding features of compound A14 within E. coli PDHc E1 were investigated to provide useful insights for the further construction of new inhibitor by molecular docking, site-directed mutagenesis, and enzymatic assays. The results indicated that A14 had most powerful inhibition against E. coli PDHc E1 due to the establishment of stronger interaction with Glu571, Met194, Glu522, Leu264 and Phe602 at active site of E.coli PDHc E1. It could be used as a lead compound for further optimization, and may have potential as a new microbicide.
- He, Haifeng,Xia, Hongying,Xia, Qin,Ren, Yanliang,He, Hongwu
-
p. 5652 - 5661
(2017/10/09)
-
- Polymer supported Zn-salen complexes: An effective one-pot oxidative esterification of aldehydes to carboxylic esters
-
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.
- Balinge, Kamlesh Rudreshwar,Khiratkar, Avinash Ganesh,Bhagat, Pundlik Rambhau
-
p. 1085 - 1095
(2017/08/08)
-
- One-Pot, Metal-Free Conversion of Anilines to Aryl Bromides and Iodides
-
A metal-free synthesis of aryl bromides and iodides from anilines via halogen abstraction from bromotrichloromethane and diiodomethane is described. This one-pot reaction affords aryl halides from the corresponding anilines in moderate to excellent yields without isolation of diazonium salts. The transformation has short reaction times, a simple workup, and insensitivity to moisture and air and avoids excess halogenation. DFT calculations support a SRN1 mechanism. This method represents a convenient alternative to the classic Sandmeyer reaction.
- Leas, Derek A.,Dong, Yuxiang,Vennerstrom, Jonathan L.,Stack, Douglas E.
-
supporting information
p. 2518 - 2521
(2017/05/24)
-
- Metal-free radical aromatic carbonylations mediated by weak bases
-
We report a new method of metal-free alkoxycarbonylation. This reaction involves the generation of aryl radicals from arenediazonium salts by a very weak base (HCO2Na) under mild conditions. Subsequent radical trapping with carbon monoxide and alcohols gives alkyl benzoates. The conditions (metal-free, 1 equiv. base, MeCN, r.t., 3 h) tolerate various functional groups (I, Br, Cl, CF3, SF5, NO2, ester). Mechanistic studies indicate the operation of a radical aromatic substitution mechanism.
- Koziakov, Denis,Jacobi Von Wangelin, Axel
-
supporting information
p. 6715 - 6719
(2017/08/22)
-
- Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
-
An efficient method for the carbonylation of (hetero) aryl pentafluorobenzenesulfonates and triflates under exceptionally mild conditions using palladium/dicobalt octacarbonyl [Pd/Co2(CO)8] has been developed. Besides acting as carbon monoxide (CO) source, Co2(CO)8enhances the reaction rate by accelerating the CO insertion through an in situ generated bimetallic palladium cobalt tetracarbonyl [Pd-Co(CO)4] complex. Under the optimized reaction condition, carbonylation of a wide range of activated and deactivated, as well as sterically hindered and heteroaromatic, substrates proceeded efficiently at room temperature. The high chemoselectivity and improved synthesis of biologically relevant Isoguvacine and Lazabemide intermediates highlights its scope as a valuable synthetic method. The generality of this protocol was further extended to other electrophiles (bromides, chlorides and tosylates). (Figure presented.).
- Joseph, Jayan T.,Sajith, Ayyiliath M.,Ningegowda, Revanna C.,Shashikanth, Sheena
-
p. 419 - 425
(2017/02/10)
-
- Selective Oxidative Esterification from Two Different Alcohols via Photoredox Catalysis
-
Esters functionalities are important building blocks that are extensively used in the chemical industry and academic laboratories. Direct oxidative esterification from easy-available alcohols to esters would be a much more appealing approach, especially using O2as terminal oxidant. Inputting external energy by photocatalysis for dioxygen activation, a mild and simple method for ester synthesis from two different alcohols has been achieved in this work. This reaction is performed under neutral conditions using O2as the terminal oxidant. A variety of primary alcohols, especially long chain alcohols and secondary alcohols are tolerated in this system.
- Yi, Hong,Hu, Xia,Bian, Changliang,Lei, Aiwen
-
-
- Combretastatin linked 1,3,4-oxadiazole conjugates as a Potent Tubulin Polymerization inhibitors
-
A new class of combretastatin linked 1,3,4-oxadiazoles were designed, synthesized and screened for their cytotoxic activity against five human cancer cell lines such as HeLa, DU-145, A549, MDA-MB-231 and B16. These compounds showed significant cytotoxicity with IC50 values in the range 0.118-54.32 μM. Conjugate 5m displayed potent antiproliferative activity against DU-145 cell line. Flow cytometric analysis revealed that these compounds arrested the cell cycle in G2/M phase. Moreover, the tubulin polymerization assay and immunofluorescence analysis indicate that 5m exhibits potent inhibitory effect on the tubulin assembly. Further, DNA fragmentation and Hoecst staining assays confirm that 5m induces apoptosis. Molecular docking studies and competitive binding assay indicated that 5m effectively bind at the colchicine binding site of the tubulin.
- Kamal, Ahmed,Srikanth,Vishnuvardhan,Kumar, G. Bharath,Suresh Babu, Korrapati,Hussaini, S.M. Ali,Kapure, Jeevak Sopanrao,Alarifi, Abdullah
-
p. 126 - 136
(2016/03/09)
-
- Synthesis, characterization and antimicrobial evaluation of novel (E)-N′-(4-(1-((3,4-dimethoxypyridin-2-yl)methyl)-1H-1,2,3-triazol-4-yl)benzylidene)benzohydrazide derivatives
-
The synthesis of novel 1,2,3-triazole-hydrazone derivatives embedded with 3,4-dimethoxy pyridine ring nucleus is described. These derivatives were prepared utilizing, 2-(chloromethyl)-3,4-dimethoxypyridine 1, 4-ethynylbenzaldehye 5 and various benzohydrazides7a-7j. The structures of the newly synthesized 1,2,3-triazole-hydrazones 8a-j was established on the basis of the spectroscopic techniques like 1H NMR, mass and IR data. They were evaluated against a panel of bacterial and fungal pathogens such as Staphylococcus. pyogens, Staphylococcus. Aureus (Gram positive bacteria), Escherichia.coli, Pseudomonas. aeruginosa (Gram negative bacteria) and Aspergillus niger and Candida albicans (Fungal stains). Compounds 8b, 8c, 8d, 8e and 8f with R = 4-OH, 4-OMe, 4-SO2Me, 3,45,-OMe and 3-NO2 respectively showed moderate antibacterial activity while compounds 8b, 8d, 8i and 8j with R = 4-OH, 4-SO2Me, 3,5-dichloro and 2,5-difluoro substitution exhibited very good fungal activity.
- Saidugari, Swamy,Vadali, Lakshmana Rao,Vidya,Ram
-
p. 2155 - 2161
(2016/10/24)
-
- Design, synthesis, pharmacological evaluation and molecular docking studies of substituted oxadiazolyl-2-oxoindolinylidene propane hydrazide derivatives
-
The manuscript describes design and synthesis of novel oxadiazolyl-2-oxoindolinylidene propane hydrazides as amide tethered hybrids of indole and oxadiazole and their evaluation for antiinflammatory and analgesic activity. The compounds were synthesized following five step reaction to yield fifteen derivatives as 3-(5-substituted-1,3,4-oxadiazol-2-yl)-N′-[2-oxo-1,2-dihydro-3Hindol-3-ylidene]propane hydrazides. The final derivatives 3-[5-(4-hydroxyphenyl)-1,3,4-oxadiazol-2-yl]-N′-[2-oxo-1,2-dihydro-3H-indol-3-ylidene]propane hydrazide and 3-[5-(4-methylphenyl)-1,3,4-oxadiazol-2-yl]-N′-[2-oxo-1,2-dihydro-3H-indol-3-ylidene]propane hydrazide were found to be highly promising molecules with severity index of 0.35 and 0.56, respectively, which is promising for an analgesic compound. The hydroxy and methyl substitution on phenyl ring system provided with active anti-inflammatory compounds having increase in reaction time of 84.11 and 83.17percent, respectively compared to standard drug at 85.84percent. Molecular docking studies exhibit comparable interaction with synthesized derivatives and standard drug having a dock score of -4.44 by the K-nearest neighbour genetic algorithm method.
- Kerzare, Deweshri,Chikhale, Rupesh,Bansode, Ratnadeep,Amnerkar, Nikhil,Karodia, Nazira,Paradkar, Anant,Khedekar, Pramod
-
p. 1998 - 2010
(2016/11/03)
-
- Cu(ii)-catalyzed esterification reaction via aerobic oxidative cleavage of C(CO)-C(alkyl) bonds
-
A novel Cu(ii)-catalyzed aerobic oxidative esterification of simple ketones for the synthesis of esters has been developed with wide functional group tolerance. This process is assumed to go through a tandem sequence consisting of α-oxygenation/esterification/nucleophilic addition/C-C bond cleavage and carbon dioxide is released as the only byproduct.
- Ma, Ran,He, Liang-Nian,Liu, An-Hua,Song, Qing-Wen
-
supporting information
p. 2145 - 2148
(2016/02/09)
-
- Efficient and practical approach to esters from acids/ 2-oxoacids/ 2-oxoaldehydes &/ 2-oxoesters
-
An efficient, mild, cost effective and practical method is presented for generation of esters (RCO2R′) from acids (RCO2H)/ 2-oxoacids (RCOCO2H)/ 2-oxoaldehydes (RCOCHO)/ 2-oxoesters (RCOCO2R″) and alcohols by using oxone as catalyst. In addition to deciphering the scope of our process, we propose a mechanism for esterification through a common intermediate IV. Reaction with 2-oxoacids and 2-oxoaldehydes proceed with initial CO-C cleavage followed by oxone mediated esterification with alcohols. In addition, reaction with 2-oxoesters proceeds through CO-CO bond cleavage and trans-esterification.
- Padala, Anil K.,Saikam, Varma,Ali, Asif,Ahmed, Qazi Naveed
-
supporting information
p. 9388 - 9395
(2015/11/18)
-
- N-(5-(QUINOLIN-6-YL)PYRIDIN-3-YL) BENZSULFAMIDE DERIVATIVES, PREPARATION METHOD AND THERAPEUTIC USE THEREOF
-
The present invention relates to the field of medical technology, and in particular, to a variety of substituted N-(5-(quinolin -6-yl)pyridin -3 -yl) bezsulfamide derivatives represented by formula (1) (groups therein are as defined in the specification).The compounds according to the present invention have favorable anti-tumor activity against human lung cancer, colon cancer, liver cancer, breast cancer and glioblastoma multiforme, which contribute to development of highly effective, low toxic and high specific anti-tumor drugs, and have high value of development. The present invention also relates to a composition, preparation method and use thereof in the preparation of anti-tumor drugs.
- -
-
Paragraph 0047
(2015/11/09)
-
- Synthesis and antimicrobial evaluation of 5-aryl-1,2,4-triazole-3-thione derivatives containing a rhodanine moiety
-
Three series of 5-aryl-1,2,4-triazole-3-thione derivatives containing a rhodanine moiety (5a-k, 6a-i, and 7a-i) have been synthesized, characterized and evaluated for their antibacterial activity. Some of these displayed potent antibacterial activity against several Gram-positive and Gram-negative bacterial strains (including multidrug-resistant clinical isolates) with minimum inhibitory concentration (MIC) values in the range of 4-64 μg/mL and minimum bactericidal concentration (MBC) values in the range of 8-256 μg/mL. Compared with previously reported rhodanine derivatives, these compounds exhibited a broad spectrum of antibacterial activity by means of introducing 4-amino-5-aryl-1,2,4-triazole-3-thione moiety. Notably, compound 5f exhibited good antibacterial activity against Staphylococcus aureus RN 4220, S. aureus 209, S. aureus 503, Gram-negative bacteria (Escherichia coli 1924), and Candida albicans 7535 with MBC values of 8 or 16 μg/ml. All of the compounds synthesized in the current Letter were characterized by 1H NMR, 13C NMR, infrared and mass spectroscopy.
- Li, Chao,Liu, Jia-Chun,Li, Ya-Ru,Gou, Cheng,Zhang, Mei-Ling,Liu, Hong-Yan,Li, Xiao-Zhen,Zheng, Chang-Ji,Piao, Hu-Ri
-
supporting information
p. 3052 - 3056
(2015/06/22)
-
- Design, synthesis and optoelectronic properties of unsymmetrical oxadiazole based indene substituted derivatives as deep blue fluoroscent materials
-
A series of novel unsymmetrically substituted indene-oxadiazole derivatives (3a-f) have been designed and synthesized by employing palladium catalysed Suzuki cross coupling reaction in high yields. The structural integrity of all the novel compounds was established by 1H, 13C NMR and LC/MS analysis. These compounds are amorphous in nature and are remarkably stable to long term storage under ambient conditions. The optoelectronic properties have been studied in detail using UV-Vis absorption and Fluorescence spectroscopy. All compounds emit intense blue to green-blue fluoroscence with high quantum yields. Time resolved measurments have shown life times in the range of 1.28 to 4.51 ns. The density functional theory (DFT) calculations were carried out for all the molecules to understand their structure-property relationships. Effect of concentration studies has been carried out in different concentrations for both absorption and emission properties and from this we have identified the optimized fluoroscence concentrations for all these compounds. The indene substituted anthracene-oxadiazole derivative (3f) showed significant red shift (λmax emi=490 nm) and emits intense green-blue fluoroscence with largest stokes shift of 145 nm. This compound also exhibited highest fluoroscence life time (τ) of 4.51 ns, which is very close to the standard dye coumarin-540A (4.63 ns) and better than fluorescein-548 (4.10 ns). The results demonstrated that the novel unsymmetrical indene-substituted oxadiazole derivatives could play important role in organic optoelectronic applications, such as organic light-emitting diodes (OLEDs) or as models for investigating the fluorescent structure-property relationship of the indene-functionalized oxadiazole derivatives.
- Belavagi, Ningaraddi S.,Deshapande, Narahari,Pujar,Wari,Inamdar,Khazi, Imtiyaz Ahmed M.
-
p. 1323 - 1330
(2015/10/20)
-
- Synthesis, characterization and optoelectronic investigations of bithiophene substituted 1,3,4-oxadiazole derivatives as green fluorescent materials
-
A series of novel unsymmetrical bithiophene substituted oxadiazole derivatives 2(a-e) were designed and synthesised by employing palladium catalysed Suzuki cross coupling reaction. These bipolar molecules consist of bithiophene as an electron donor unit (D) and electron transporting oxadiazole as acceptor unit (A). The structural integrity of all the new compounds was confirmed by 1H NMR, 13C NMR and GC-MS analysis. The photophysical and electrochemical properties have been studied in detail using UV-Vis absorption, fluorescence spectroscopy and CV measurements. All compounds emit intense green fluorescence with good quantum yields. Density functional theory computations have been carried out to understand the structure-property relationship, the computed values are found to be in good agreement with the experimental results. The results demonstrated that the novel bithiophene containing oxadiazole derivatives could play an important role in organic optoelectronics.
- Deshapande, Narahari,Belavagi, Ningaraddi S.,Sunagar, Manjunath G.,Gaonkar, Supreet,Pujar,Wari,Inamdar,Khazi, Imtiyaz Ahmed M.
-
p. 86685 - 86696
(2015/11/02)
-
- Synthesis of novel triazoles and a tetrazole of escitalopram as cholinesterase inhibitors
-
A novel serie of escitalopram triazoles (60-88) and a tetrazole (89) have been synthesized and subjected to a study to establish the inhibitory potential of these compounds toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Some selectivity in inhibition has been observed. The 4-chlorophenyl- (75, IC50, 6.71 ± 0.25 μM) and 2-methylphenyl- (70, IC50, 9.52 ± 0.23 μM) escitalopram triazole derivatives depicted high AChE inhibition, while 2-fluorophenyl- (76, IC50 = 4.52 ± 0.17 μM) and 4-fluorophenyl- (78, IC50 = 5.31 ± 0.43 μM) have found to be excellent BChE inhibitors. It has also been observed that ortho, meta and para substituted electron donating groups increase the inhibition, while electron withdrawing groups reduce the inhibition. Docking analyses of inhibitors with AChE have depicted the binding energies for 70 and 75 as ΔGbind -6.42 and -6.93 kcal/mol, respectively, while ligands 76 and 78 have shown the binding affinity ΔGbind -9.04 and -8.51 kcal/mol, respectively, for BChE.
- Mehr-Un-Nisa,Munawar, Munawar A.,Chattha, Fauzia A.,Kousar, Samina,Munir, Jawaria,Ismail, Tayaba,Ashraf, Muhammad,Khan, Misbahul A.
-
p. 6014 - 6024
(2015/11/11)
-
- Synthesis and antimicrobial activity of new imidazole-hydrazone derivatives
-
Hydrazones demonstrated significant antimicrobial activity, antitubercular activity and antitumoral activity in medicinal areas. The imidazole nucleus is well known to play an important role in living organisms since it is incorporated into the histidine molecule and many other important biological, pharmacological and therapeutic activities. Condensation of 4-phenyl-1H-imidazole-2-carbaldehyde (3) with various selected benzohydrazides (4a-m) resulted in imidazole-hydrazone derivatives (5a-m). They were evaluated for antibacterial and antifungal activity against A. Niger, C. albicans (fungal strains), E. coli and P. aeruginosa (Gram-negative bacteria), S. aureus and S. pyogenes (Gram-positive bacteria) using griseofluvin (for fungi) and ciprofloxacin (for bacteria) as the standard drugs. In general, it is observed that most of the compounds were found to be potent against both the bacterial and fungal strains.
- Prasanna, V. Laxmi,Narender
-
p. 3605 - 3608
(2015/12/24)
-
- Metal-free aerobic oxidative esterification of aldehydes in the presence of cyanide
-
A metal-free aerobic oxidative esterification of aldehydes in the presence of cyanide is described. Various aromatic aldehydes and sterically congested alcohols were amenable to this protocol. In addition, this method could be extended to the preparation of thioesters with a thiol in place of an alcohol. Furthermore, the cyanide-mediated aerobic oxidation of aldehydes was applied to the synthesis of lactones via intramolecular esterification in the absence of an alcohol.
- Kim, Yoo-Jin,Cheon, Cheol-Hong
-
supporting information
p. 2055 - 2061
(2015/08/18)
-
- Conversion of a metal-organic framework to N-doped porous carbon incorporating Co and CoO nanoparticles: Direct oxidation of alcohols to esters
-
A Co-based metal-organic framework, ZIF-67, has been exploited as a selflate to afford N-doped porous carbon incorporating Co NPs with surface-oxidized CoO species, which exhibit excellent catalytic activity, selectivity and magnetic recyclability toward the direct oxidation of alcohols to esters with O2 as a benign oxidant under mild conditions.
- Zhou, Yu-Xiao,Chen, Yu-Zhen,Cao, Lina,Lu, Junling,Jiang, Hai-Long
-
supporting information
p. 8292 - 8295
(2015/05/13)
-
- Highly efficient, general hydrogenation of aldehydes catalyzed by PNP iron pincer complexes
-
A general protocol for the synthetically and industrially important hydrogenation of aldehydes to alcohols is reported. The reactions are catalyzed by well-defined iron pincer complexes that are capable of hydrogenation of aliphatic and aromatic aldehydes selectively and efficiently under mild conditions, with unprecedented turnover numbers.
- Zell, Thomas,Ben-David, Yehoshoa,Milstein, David
-
p. 822 - 826
(2015/02/19)
-
- Design, synthesis, molecular docking and 3D-QSAR studies of potent inhibitors of enoyl-acyl carrier protein reductase as potential antimycobacterial agents
-
In order to develop a lead antimycobacterium tuberculosis compound, a series of 52, novel pyrrole hydrazine derivatives have been synthesized and screened which target the essential enoyl-ACP reductase. The binding mode of the compounds at the active site of enoyl-ACP reductase was explored using surflex-docking method. The binding model suggests one or two hydrogen bonding interactions between pyrrole hydrazones and InhA enzyme. Highly active compound 5r (MIC 0.2 μg/mL) showed hydrogen bonding interactions with Tyr158 and NAD+ in the same manner as those of ligands PT70 and triclosan. The CoMFA and CoMSIA models generated with database alignment were the best in terms of overall statistics. The predictive ability of the CoMFA and CoMSIA models was determined using a test set of 13 compounds, which gave predictive correlation coefficients (rpred2) of 0.896 and 0.930, respectively.
- More, Uttam A.,Joshi, Shrinivas D.,Aminabhavi, Tejraj M.,Gadad, Andanappa K.,Nadagouda, Mallikarjuna N.,Kulkarni, Venkatrao H.
-
p. 199 - 218
(2014/01/06)
-