- Synthesis, characterization, antioxidant activities, and DNA-binding studies of (E)-N′-[1-(pyridin-2-yl)ethylidene]isonicotinohydrazide and its Pr(III) and Nd(III) complexes
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A new ligand, (E)-N′-[1-(pyridin-2-yl)ethylidene]isonicotinohydrazide (HL), was prepared by condensation of 2-acetylpyridine and isonicotinohydrazide in ethanol. Its two lanthanide(III) complexes, [NdIII(L) 2(NO3)(CH3OH)2]?CH 3CH2OH (1), and [PrIII(L)2(NO 3)(CH3OH)2]?CH3CH 2OH (2), have been synthesized and characterized on the basis of element analyses, molar conductivities and IR spectra. The structure of complex 2 has been confirmed by X-ray diffraction. In addition, the DNA-binding properties of the two complexes have been investigated by electronic absorption spectroscopy, fluorescence spectroscopy, circular dichroic (CD) spectroscopy and viscosity measurements. The experimental results suggest that the two complexes bind to DNA via a groove binding mode, and the binding affinity of complex 2 is higher than that of complex 1. Furthermore, the antioxidant activities (superoxide and hydroxyl radical) of the ligand and its metal complexes were determined by spectrophotometry methods in vitro. These complexes were found to possess potent antioxidant activity and be superior to standard antioxidant like mannitol.
- Hao, Zhong-Yan,Liu, Qi-Wan,Xu, Jun,Jia, Lei,Li, Shao-Bai
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Read Online
- Adamantyl derivative as a potent inhibitor of plasmodium FK506 binding protein 35
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FKBP35, FK506 binding protein family member, in Plasmodium species displays a canonical peptidyl-prolyl isomerase (PPIase) activity and is intricately involved in the protein folding process. Inhibition of PfFKBP35 by FK506 or its analogues were shown to interfere with the in vitro growth of Plasmodium falciparum. In this study, we have synthesized adamantyl derivatives, Supradamal (SRA/4a) and its analogues SRA1/4b and SRA2/4c, which demonstrate submicromolar inhibition of Plasmodium falciparum FK506 binding domain 35 (FKBD35) PPIase activity. SRA and its analogues not only inhibit the in vitro growth of Plasmodium falciparum 3D7 strain but also show stage specific activity by inhibiting the trophozoite stage of the parasite. SRA/4a also inhibits the Plasmodium vivax FKBD35 PPIase activity and our crystal structure of PvFKBD35 in complex with the SRA provides structural insights in achieving selective inhibition against Plasmodium FKBPs.
- Harikishore, Amaravadhi,Leow, Min Li,Niang, Makhtar,Rajan, Sreekanth,Pasunooti, Kalyan Kumar,Preiser, Peter Rainer,Liu, Xuewei,Yoon, Ho Sup
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- Transition metal complexes of N′-(2-(hydroxyimino)propanoyl)isonicotinohydrazide: Synthesis, characterization, DNA interaction and anticancer evaluation
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A new tetradentate chelating ligand, N′-(2-(hydroxyimino)propanoyl)isonicotinohydrazide and its selective transition metal complexes have been synthesized and evaluated for anticancer behavior. The ligand structure was determined by single-crystal X-ray crystallography. All complexes were investigated by elemental, thermogravimetric analysis, IR, NMR, ESI Mass and electronic spectroscopic studies. The ligand exhibited monoclinic lattice structure with Cc space group, having 4 ligand molecules in each unit cell. The geometrical isomerism (E and Z) was observed in ligand due to the restricted rotation along the >C[dbnd]N– functional group. The interaction of ligand and complexes with calf-thymus DNA (CT-DNA) has been extensively studied using absorption, emission, viscosity and thermal denaturation studies with E. coli DNA. The DNA cleavage properties were screened using plasmid pBR322 DNA by gel electrophoresis method. Complexes have been evaluated for their in vitro antiproliferative activity against human cancer cells of different origin such as MCF-7, Mia-Pa-Ca-2 and DU-145 by using SRB (sulforhodamine B) assay, in which iron complex have shown better antiproliferative activity compared to remaining complexes.
- Hegde, Divya,Naik, Ganesh N.,Vadavi, Ramesh S.,Shyam Kumar,Barretto, Delicia A.,Gudasi, Kalagouda B.
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- Development of a Novel Chemoenzymatic Process for (S)-1-(Pyridin-4-yl)-1,3-propanediol
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We first developed a novel and efficient chemoenzymatic process to prepare (S)-1-(pyridin-4-yl)-1,3-propanediol, a vital HepDirect prodrug intermediate, from inexpensive and commercially available isonicotinic acid. Through this process, we provide a creative way to obtain the key chiral intermediate, β-hydroxyester, with ketoreductase (KRED) EA. After optimization of the process, we performed the reaction on a 100 g scale with a substrate concentration of up to 150 g/L, a yield of 93%, and an ee value of up to 99.9%. Additionally, we used a simple and effective NaBH4/MgCl2 reduction system to obtain (S)-1-(pyridin-4-yl)-1,3-propanediol with >99.9% ee and an 80% yield. This novel chemoenzymatic process has the potential to be a cost-effective and environmentally friendly process suitable for industrial use.
- Chen, Shao-Xin,Peng, Peng,Tang, Jia-Wei,Wang, Hong-Yi,Yan, Hai-Jun,Zhang, Fu-Li
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- Pleuromutilin derivative with 1, 3, 4-oxadiazole side chain and preparation and application thereof
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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.
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Paragraph 0055-0056; 0070; 0090; 0092; 0095; 0102
(2021/07/24)
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- Fluorovinylsulfones and -Sulfonates as Potent Covalent Reversible Inhibitors of the Trypanosomal Cysteine Protease Rhodesain: Structure-Activity Relationship, Inhibition Mechanism, Metabolism, and in Vivo Studies
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Rhodesain is a major cysteine protease of Trypanosoma brucei rhodesiense, a pathogen causing Human African Trypanosomiasis, and a validated drug target. Recently, we reported the development of α-halovinylsulfones as a new class of covalent reversible cysteine protease inhibitors. Here, α-fluorovinylsulfones/-sulfonates were optimized for rhodesain based on molecular modeling approaches. 2d, the most potent and selective inhibitor in the series, shows a single-digit nanomolar affinity and high selectivity toward mammalian cathepsins B and L. Enzymatic dilution assays and MS experiments indicate that 2d is a slow-tight binder (Ki = 3 nM). Furthermore, the nonfluorinated 2d-(H) shows favorable metabolism and biodistribution by accumulation in mice brain tissue after intraperitoneal and oral administration. The highest antitrypanosomal activity was observed for inhibitors with an N-terminal 2,3-dihydrobenzo[b][1,4]dioxine group and a 4-Me-Phe residue in P2 (2e/4e) with nanomolar EC50 values (0.14/0.80 μM). The different mechanisms of reversible and irreversible inhibitors were explained using QM/MM calculations and MD simulations.
- Jung, Sascha,Fuchs, Natalie,Johe, Patrick,Wagner, Annika,Diehl, Erika,Yuliani, Tri,Zimmer, Collin,Barthels, Fabian,Zimmermann, Robert A.,Klein, Philipp,Waigel, Waldemar,Meyr, Jessica,Opatz, Till,Tenzer, Stefan,Distler, Ute,R?der, Hans-Joachim,Kersten, Christian,Engels, Bernd,Hellmich, Ute A.,Klein, Jochen,Schirmeister, Tanja
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p. 12322 - 12358
(2021/09/02)
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- Development of Novel (+)-Nootkatone Thioethers Containing 1,3,4-Oxadiazole/Thiadiazole Moieties as Insecticide Candidates against Three Species of Insect Pests
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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
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p. 15544 - 15553
(2022/01/03)
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- Design, synthesis, in vitro and in vivo evaluation against MRSA and molecular docking studies of novel pleuromutilin derivatives bearing 1, 3, 4-oxadiazole linker
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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
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- Metal-Free Deoxygenation of Amine N-Oxides: Synthetic and Mechanistic Studies
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We report herein an unprecedented combination of light and P(III)/P(V) redox cycling for the efficient deoxygenation of aromatic amine N-oxides. Moreover, we discovered that a large variety of aliphatic amine N-oxides can easily be deoxygenated by using only phenylsilane. These practically simple approaches proceed well under metal-free conditions, tolerate many functionalities and are highly chemoselective. Combined experimental and computational studies enabled a deep understanding of factors controlling the reactivity of both aromatic and aliphatic amine N-oxides.
- Lecroq, William,Schleinitz, Jules,Billoue, Mallaury,Perfetto, Anna,Gaumont, Annie-Claude,Lalevée, Jacques,Ciofini, Ilaria,Grimaud, Laurence,Lakhdar, Sami
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p. 1237 - 1242
(2021/06/01)
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- A facile and versatile electro-reductive system for hydrodefunctionalization under ambient conditions
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A general electrochemical system for reductive hydrodefunctionalization is described, employing the inexpensive and easily available triethylamine (Et3N) as a sacrificial reductant. This protocol is characterized by facile operation, sustainable conditions, and exceptionally wide substrate scope covering the cleavage of C-halogen, N-S, N-C, O-S, O-C, C-C and C-N bonds. Notably, the selectivity and capability of reduction can be conveniently switched by simple incorporation or removal of an alcohol as a co-solvent.
- Huang, Binbin,Guo, Lin,Xia, Wujiong
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supporting information
p. 2095 - 2103
(2021/03/26)
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- Manganese-catalysed transfer hydrogenation of esters
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Manganese catalysed ester reduction using ethanol as a hydrogen transfer agent in place of dihydrogen is reported. High yields can be achieved for a range of substrates using 1 mol% of a Mn(i) catalyst, with an alkoxide promoter. The catalyst is derived from a tridentate P,N,N ligand.
- Oates, Conor L.,Widegren, Magnus B.,Clarke, Matthew L.
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supporting information
p. 8635 - 8638
(2020/08/21)
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- Design, synthesis, biological activity, crystal structure and theoretical calculations of novel 1,2,4-triazole derivatives
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Series of 1,2,4-triazole Schiff base (Ia-f) were designed and synthesized. Their in-vitro antifungal activity to pythium solani, gibberlla nicotiancola, fusarium oxysporium fs.p. niveum and gibberlla saubinetii were evaluated. The results showed compound If exhibited good activity with tested fungi, which indicated that 1,2,4-triazole scaffold with introduction of imidazole phenyl could keep the antifungal activity. In order to further research the compound If, the crystal structure was detected by X-ray diffraction. Meanwhile, the FT-IR, FT-Raman, natural bond orbital (NBO), HOMO-LUMO and MEP were calculated at B3LYP/6-311G+(d,p) level. All the results will be helpful for further drug design in 1,2,4-triazole analogues.
- Jin, Ruyi,Wang, Yanyan,Guo, Hui,Long, Xu,Li, Jiajia,Yue, Shijun,Zhang, Shuan,Zhang, Guanghui,Meng, Qinghua,Wang, Chuan,Yan, Hao,Tang, Yuping,Zhou, Sha
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- Preparation method of isoniazid
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The invention discloses a preparation method of isoniazide, comprising the following steps: carrying out an esterification reaction among isonicotinic acid, alcohol and an acylation reagent to generate isonicotinate, carrying out a reaction between isonicotinate and an ether reagent in an alcoholic solution of hydrogen chloride to generate isonicotinate hydrochloride, condensing with hydrazine hydrate to generate an isoniazide crude product, and refining to obtain the finished product. According to the method, by adding the step of reacting isonicotinate to generate isonicotinate hydrochloride, on one hand, the subsequent condensation hydrazinolysis reaction time can be greatly shortened and preparation efficiency is improved; on the other hand, isonicotinic acid which is not fully reacted, isonicotinamide introduced by an isonicotinic acid raw material and potential 2-picolinic acid impurities can be removed, the purity of the finally obtained isoniazide is as high as 99.99%, and thesingle impurity content is smaller than 0.10%. The preparation method is mild in reaction condition, easy to operate, good in product quality, high in yield, high in preparation speed and suitable forindustrial production.
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Paragraph 0079-0080
(2020/06/02)
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- 4-Amino-1,2,4-triazole-3-thione-derived Schiff bases as metallo-β-lactamase inhibitors
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Resistance to β-lactam antibiotics in Gram-negatives producing metallo-β-lactamases (MBLs) represents a major medical threat and there is an extremely urgent need to develop clinically useful inhibitors. We previously reported the original binding mode of 5-substituted-4-amino/H-1,2,4-triazole-3-thione compounds in the catalytic site of an MBL. Moreover, we showed that, although moderately potent, they represented a promising basis for the development of broad-spectrum MBL inhibitors. Here, we synthesized and characterized a large number of 4-amino-1,2,4-triazole-3-thione-derived Schiff bases. Compared to the previous series, the presence of an aryl moiety at position 4 afforded an average 10-fold increase in potency. Among 90 synthetic compounds, more than half inhibited at least one of the six tested MBLs (L1, VIM-4, VIM-2, NDM-1, IMP-1, CphA) with Ki values in the μM to sub-μM range. Several were broad-spectrum inhibitors, also inhibiting the most clinically relevant VIM-2 and NDM-1. Active compounds generally contained halogenated, bicyclic aryl or phenolic moieties at position 5, and one substituent among o-benzoic, 2,4-dihydroxyphenyl, p-benzyloxyphenyl or 3-(m-benzoyl)-phenyl at position 4. The crystallographic structure of VIM-2 in complex with an inhibitor showed the expected binding between the triazole-thione moiety and the dinuclear centre and also revealed a network of interactions involving Phe61, Tyr67, Trp87 and the conserved Asn233. Microbiological analysis suggested that the potentiation activity of the compounds was limited by poor outer membrane penetration or efflux. This was supported by the ability of one compound to restore the susceptibility of an NDM-1-producing E. coli clinical strain toward several β-lactams in the presence only of a sub-inhibitory concentration of colistin, a permeabilizing agent. Finally, some compounds were tested against the structurally similar di-zinc human glyoxalase II and found weaker inhibitors of the latter enzyme, thus showing a promising selectivity towards MBLs.
- Baud, Damien,Bebrone, Carine,Becker, Katja,Benvenuti, Manuela,Cerboni, Giulia,Chelini, Giulia,Cutolo, Giuliano,De Luca, Filomena,Docquier, Jean-Denis,Feller, Georges,Fischer, Marina,Galleni, Moreno,Gavara, Laurent,Gresh, Nohad,Kwapien, Karolina,Legru, Alice,Mangani, Stefano,Mercuri, Paola,Pozzi, Cecilia,Sannio, Filomena,Sevaille, Laurent,Tanfoni, Silvia,Verdirosa, Federica,Berthomieu, Dorothée,Bestgen, Beno?t,Frère, Jean-Marie,Hernandez, Jean-Fran?ois
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supporting information
(2020/09/16)
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- Preparation method of 4-ethylpyridine
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The invention relates to the technical field of organic synthesis, in particular to a preparation method of 4-ethylpyridine. The preparation method of the 4-ethylpyridine comprises the following stepsof: mixing ethyl 4-picolinate with sodium ethoxide, heating to 90 to 110 DEG C, then dropwise adding ethyl acetate, and carrying out claisen condensation reaction, thus obtaining ethyl 3-oxo-3-(4-pyridyl) propionate; mixing the ethyl 3-oxo-3-(4-pyridyl) propionate, dimethyl sulfoxide and water, and carrying out heating treatment, thus obtaining 4-acetylpyridine; cooling after mixing glycol with potassium hydroxide, adding hydrazine hydrate, rising the temperature to 60 to 80 DEG C, then mixing with the 4-acetylpyridine, and carrying out reduction reaction, thus obtaining the 4-ethylpyridine.The 4-ethylpyridine prepared through the preparation method provided by the invention is higher in yield and purity.
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Paragraph 0039; 0060-0063; 0070-0073; 0080-0083
(2019/04/10)
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- new synthesis method of 4-pyridine formaldehyde
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The invention belongs to the field of organic matter matter synthesis, and particularly relates to a new synthesis method of 4-pyridine formaldehyde, wherein isonicotinic acid is used as a starting raw material, and is subjected to esterifying and hydrazinolysis to synthesize isoniazid, and the isoniazid is oxidized into 4-pyridine formaldehyde by using recyclable K3[Fe(CN)]6 as an oxidant. According to the present invention, the new synthesis method is used so as to achieve advantages of economical raw material, few step, no environment pollution, simple operation and yield improving.
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Paragraph 0010; 0011
(2019/05/16)
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- Targeting malaria and leishmaniasis: Synthesis and pharmacological evaluation of novel pyrazole-1,3,4-oxadiazole hybrids. Part II
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In continuance with earlier reported work, an extension has been carried out by the same research group. Mulling over the ongoing condition of resistance to existing antimalarial agents, we had reported synthesis and antimalarial activity of certain pyrazole-1,3,4-oxadiazole hybrid compounds. Bearing previous results in mind, our research group ideated to design and synthesize some more derivatives with varied substitutions of acetophenone and hydrazide. Following this, derivatives 5a–r were synthesized and tested for antimalarial efficacy by schizont maturation inhibition assay. Further, depending on the literature support and results of our previous series, certain potent compounds (5f, 5n and 5r) were subjected to Falcipain-2 inhibitory assay. Results obtained for these particular compounds further strengthened our hypothesis. Here, in this series, compound 5f having unsubstituted acetophenone part and a furan moiety linked to oxadiazole ring emerged as the most potent compound and results were found to be comparable to that of the most potent compound (indole bearing) of previous series. Additionally, depending on the available literature, compounds (5a–r) were tested for their antileishmanial potential. Compounds 5a, 5c and 5r demonstrated dose-dependent killing of the promastigotes. Their IC50 values were found to be 33.3 ± 1.68, 40.1 ± 1.0 and 19.0 ± 1.47 μg/mL respectively. These compounds (5a, 5c and 5r) also had effects on amastigote infectivity with IC50 of 44.2 ± 2.72, 66.8 ± 2.05 and 73.1 ± 1.69 μg/mL respectively. Further target validation was done using molecular docking studies. Acute oral toxicity studies for most active compounds were also performed.
- Verma, Garima,Khan, Mohemmed Faraz,Mohan Nainwal, Lalit,Ishaq, Mohd,Akhter, Mymoona,Bakht, Afroz,Anwer, Tariq,Afrin, Farhat,Islamuddin, Mohammad,Husain, Ibraheem,Alam, Mohammad Mumtaz,Shaquiquzzaman, Mohammad
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- Synthesis of novel indole derivatives containing double 1,3,4-oxadiazole moiety as efficient bactericides against phytopathogenic bacterium Xanthomonas oryzae
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Abstract: A series of novel indole derivatives containing double 1,3,4-oxadiazole moiety was designed, synthesized and evaluated for their antibacterial activities in vitro. These compounds were fully characterized by 1H NMR, 13C NMR, and HRMS. Bioassay results indicated that most of title compounds exhibited excellent antibacterial activities against rice bacterial pathogen Xanthomonas oryzae (Xoo). For example, compounds 7d, 7h, 7i, 7j, 7k, 7l and 7m had the half-maximal effective concentration (EC50) values of 52.31, 54.12, 40.65, 38.80, 51.13, 52.75 and 50.66?μg/mL, respectively, which was better than that of commercial product bismerthiazol (BMT) (85.18?μg/mL). The experimental results proved that indole derivatives bearing double 1,3,4-oxadiazole unit are promising candidates for the development of new agricultural bactericides against pathogenic bacterium Xoo. Graphical abstract: [Figure not available: see fulltext.].
- Tian, Kun,Li, Xiao-Qin,Zhang, Li,Gan, Yi-Yuan,Meng, Jiao,Wu, Shou-Qun,Wan, Jin-Lin,Xu, Yang,Cai, Chao-Ting,Ouyang, Gui-Ping,Wang, Zhen-Chao
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- Design, synthesis, biological activities and DFT calculation of novel 1,2,4-triazole Schiff base derivatives
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Series of 1,2,4-triazole Schiff bases (2a-2d, 2f-2h and 3a-3h) have been designed and synthesized. The structure of title compounds was confirmed on the basis of their spectral data and elemental analysis. All the target compounds were screened for their in vitro antifungal activity and antibacterial activity. Two of the tested compounds (2a and 2b) exhibited significant antifungal activity against most fungi, especially compound 2a showed better antifungal activity than triadimefon. Meanwhile, the antibacterial activity assay also indicated compound 2a exhibited excellent antibacterial activities comparable to chloramphenicol. The SAR manifested no substitution at position 5 of the triazole ring caused an increase in activity, and 3-phenoxy phenyl group introduced in 1,2,4-triazole scaffold can enhance the antibacterial activity. The DFT calculation indicated triazole ring, S atom and benzene ring in both of the 2a and 3a make a major contribution to the activity.
- Jin, Ru-Yi,Zeng, Chu-Yue,Liang, Xu-Hua,Sun, Xiao-Hong,Liu, Yuan-Fa,Wang, Yan-Yan,Zhou, Sha
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p. 253 - 260
(2018/07/06)
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- Design, Synthesis, and Antifungal Activities of Novel 1,2,4-Triazole Schiff Base Derivatives
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With the aim to find new compounds with high antifungal activity, 21 4-amino-5-substituted-1,2,4-triazole Schiff bases (2a?–?2g, 3a?–?3g, and 4a?–?4g) were designed and synthesized. Their antifungal activities against Pythium solani, Gibberlla nicotiancola, Fusarium oxysporium f. sp. niveum, Gibberlla saubinetii, Alternaria iycopersici, Phytophthora capsici, Physalospora piricola, Cercospora arachidicola hori, and Fusarium oxysporium f. sp. cucumber were tested, parts of the compounds exhibited excellent antifungal activity. This research provides useful information for further study of antifungal agents.
- Jin, Ruyi,Liu, Jingli,Zhang, Guanghui,Li, Jiajia,Zhang, Shuan,Guo, Hui
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- A preparation method of isoniazid (by machine translation)
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The invention discloses a preparation method of isoniazid. The method comprises the following steps: 1) performing esterification reaction to isonicotinic acid, alcohol and acylating reagent to obtain isonicotinic acid ester; 2) performing condensation reaction to isonicotinic acid ester and hydrazine hydrate and performing post-treatment to reaction liquid to obtain isoniazid finished products. The isoniazid is prepared firstly through esterification of isonicotinic acid and alcohol and then condensation of the obtained ester and hydrazine hydrate. The method can well control the content of impurities in the target product isoniazid, high-purity isoniazid can be obtained, the purity is above 99.9 percent and the content of individual impurity is smaller than 0.10 percent. The method is simple to operate, is easy to control and is applicable to industrial operation. In addition, by using recovered isonicotinic acid to prepare isoniazid, the cyclic utilization of resources can be realized, the waste emission is reduced, the cost is reduced and the method is very suitable for industrial production.
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Paragraph 0059-0067
(2018/11/03)
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- 1,2,4-Triazole-3-thione Compounds as Inhibitors of Dizinc Metallo-β-lactamases
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Metallo-β-lactamases (MBLs) cause resistance of Gram-negative bacteria to β-lactam antibiotics and are of serious concern, because they can inactivate the last-resort carbapenems and because MBL inhibitors of clinical value are still lacking. We previously identified the original binding mode of 4-amino-2,4-dihydro-5-(2-methylphenyl)-3H-1,2,4-triazole-3-thione (compound IIIA) within the dizinc active site of the L1 MBL. Herein we present the crystallographic structure of a complex of L1 with the corresponding non-amino compound IIIB (1,2-dihydro-5-(2-methylphenyl)-3H-1,2,4-triazole-3-thione). Unexpectedly, the binding mode of IIIB was similar but reverse to that of IIIA. The 3 D structures suggested that the triazole–thione scaffold was suitable to bind to the catalytic site of dizinc metalloenzymes. On the basis of these results, we synthesized 54 analogues of IIIA or IIIB. Nineteen showed IC50 values in the micromolar range toward at least one of five representative MBLs (i.e., L1, VIM-4, VIM-2, NDM-1, and IMP-1). Five of these exhibited a significant inhibition of at least four enzymes, including NDM-1, VIM-2, and IMP-1. Active compounds mainly featured either halogen or bulky bicyclic aryl substituents. Finally, some compounds were also tested on several microbial dinuclear zinc-dependent hydrolases belonging to the MBL-fold superfamily (i.e., endonucleases and glyoxalase II) to explore their activity toward structurally similar but functionally distinct enzymes. Whereas the bacterial tRNases were not inhibited, the best IC50 values toward plasmodial glyoxalase II were in the 10 μm range.
- Sevaille, Laurent,Gavara, Laurent,Bebrone, Carine,De Luca, Filomena,Nauton, Lionel,Achard, Maud,Mercuri, Paola,Tanfoni, Silvia,Borgianni, Luisa,Guyon, Carole,Lonjon, Pauline,Turan-Zitouni, Gülhan,Dzieciolowski, Julia,Becker, Katja,Bénard, Lionel,Condon, Ciaran,Maillard, Ludovic,Martinez, Jean,Frère, Jean-Marie,Dideberg, Otto,Galleni, Moreno,Docquier, Jean-Denis,Hernandez, Jean-Fran?ois
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p. 972 - 985
(2017/06/27)
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- Method for preparing aminopyridine from methylpyridine, and purifying method of aminopyridine
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The invention relates to the field of organic synthesis, and concretely relates to a method for preparing aminopyridine from methylpyridine, and a purifying method of aminopyridine. Crude aminopyridine is prepared from corresponding methylpyridine through oxidation, esterification, hydrazinolysis and rearrangement reactions, the reaction yield of every step is high, and a post-treatment technology is easy to industrially operate; in the oxidation reaction, beta-cyclodextrin is used as a catalyst, so the conversion rate of the oxidation reaction is increased, and the generation of byproducts is reduced; and anhydrous ethanol and an alkane reagent are used to re-crystallize the crude aminopyridine, and a decolorizing agent is combined, and the purity of the final product reaches 98% or more; and the purifying method has the advantages of simplicity, easiness in operation, easily available raw materials, and suitableness for industrial production.
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- Synthesis of Schiff bases of 4-Amino-3-mercapto-5-pyridin-4yl-4H-1,2,4-triazole and their evaluation as SAR inducers
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A series of twenty five Schiff bases 6a-y of 4-Amino-3-mercapto-5-pyridin-4yl-4H-1,2,4-triazole having different substitution in the aryl ring attached to imine group designed incorporating the isonicotinic acid moiety present in INA, a known SAR inducer have been synthesized and characterized using 1H and 13C NMR, FT-IR spectroscopy and elemental analysis. All twenty five Schiff bases, 4-Arylideneamino-3-mercapto-5-pyridin-4-yl-4H-1,2,4-triazoles have been screened for systemic acquired resistance (SAR) inducing activity against sheath blight of rice and five potential compounds viz. 6f, 6g, 6r, 6t and 6u analogues have been further evaluated. All the five compounds have considerably decreased the relative lesion height (RLH) as compared to control with maximum reduction in RLH shown by compound 6u (47.15%). These five potential compounds have been further studied for their effect on phenol content, PAL and peroxidase activity. The compound 6u has been identified as the most potent SAR inducer both based on phenotypic and biochemical study and also does not show direct fungicidal activity against R. solani. Its RI activity is found better than 2,6-dichloroisonicotinic acid (INA), a resistance inducing chemical used as standard.
- Majumder, Sujan,Bashyal, Bishnu Maya,Gupta
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p. 1260 - 1274
(2015/11/25)
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- Potent antimicrobial agents against azole-resistant fungi based on pyridinohydrazide and hydrazomethylpyridine structural motifs
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Abstract Schiff base derivatives have recently been shown to possess antimicrobial activity, and these derivatives include a limited number of salicylaldehyde hydrazones. To further explore this structure-activity relationship between salicylaldehyde hydrazones and antifungal activity, we previously synthesized and analyzed a large series of salicylaldehyde and formylpyridinetrione hydrazones for their ability to inhibit fungal growth of both azole-susceptible and azole-resistant species of Candida. While many of these analogs showed excellent growth inhibition with low mammalian cell toxicity, their activity did not extend to azole-resistant species of Candida. To further dissect the structural features necessary to inhibit azole-resistant fungal species, we synthesized a new class of modified salicylaldehyde derivatives and subsequently identified a series of modified pyridine-based hydrazones that had potent fungicidal antifungal activity against multiple Candida spp. Here we would like to present our synthetic procedures as well as the results from fungal growth inhibition assays, mammalian cell toxicity assays, time-kill assays and synergy studies of these novel pyridine-based hydrazones on both azole-susceptible and azole-resistant fungal species.
- Backes, Gregory L.,Jursic, Branko S.,Neumann, Donna M.
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p. 3397 - 3407
(2015/08/03)
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- Synthesis, antiproliferative activity, and molecular docking studies of curcumin analogues bearing pyrazole ring
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Several curcumin analogues bearing pyrazole were synthesized and characterized by IR, NMR, and mass spectral data. There were four tested compounds among 11 synthesized compounds, which were evaluated for antiproliferative activity and showed significant activity in both one-dose and five-dose assays. The antiproliferative effects were tested on a panel of 60 cell lines, according to the National Cancer Institute screening protocol. The most active compounds among the series were 3,5-bis(4-hydroxy-3-methylstyryl)-1H-pyrazole-1-carboxamide (3k) which showed mean percent growth inhibition of 116.09 in one-dose assay at 10 μM, and GI50 values were ranging between 0.0912 and 2.36 μM in five-dose assay. The best results were recorded on the leukaemia cell lines with value ranging from 0.0912 to 0.365 μM. All the tested compounds showed broad-spectrum antiproliferative activity over different cancer cell lines. When compared with the standard drug paclitaxel, the compound 3k showed superior activity on nearly 42 cell lines. The molecular docking study was performed to explore the binding interaction of these curcumin analogues with the active site of EGFR tyrosine kinase (EGFR-TK). The hydroxyl group of both phenyl rings was important for the rein-geminated hydrogen bonding by either side chain or backbone with the active site of EGFR-TK. Graphical Abstract: Four curcumin analogues were evaluated for their antiproliferative activity and showed promising results. The molecular docking studies showed that all the compounds (3a-k) were well accommodated in the EGFR tyrosine kinase.[Figure not available: see fulltext.]
- Ahsan, Mohamed Jawed,Choudhary, Kavita,Jadav, Surender Singh,Yasmin, Sabina,Ansari, Md. Yousuf,Sreenivasulu, Reddymasu
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p. 4166 - 4180
(2015/11/02)
-
- Chemistry and antioxidant properties of titanium(IV) complexes
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Abstract The synthesis of titanium(IV) complexes with biologically active hydrazide ligands has been carried out. The complexes were characterized by spectroscopic methods (IR, 1H NMR and 13C NMR), elemental analysis and conductivity studies. These studies suggest bidentate coordination of the ligands through carbonyl oxygen and primary amine nitrogen, resulting in octahedral geometries. Hydrazides with pyridyl substituents displayed 1:2 metal-to-ligand ratio, and hydrazides with imino substituents exhibited 1:3 metal-to-ligand ratio resulting in an outer sphere complex. The remaining complexes displayed inner sphere coordination with 1:1 metal-to-ligand ratio. These complexes exhibit varying degrees of radical scavenging properties against DPPH, superoxide and nitric oxide free radicals. The free ligands showed inhibition against DPPH but were inactive against superoxide and nitric oxide free radicals. The structure-activity relationships of the complexes are discussed.
- Shaikh, Zara,Ashiq, Uzma,Jamal, Rifat Ara,Mahroof-Tahir, Mohammad,Shamshad, Bushra,Sultan, Sadaf
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p. 665 - 671
(2015/08/06)
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- An efficient renewable-derived surfactant for aqueous esterification reactions
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An efficient and simple approach for the aqueous esterification of a range of carboxylic acids with alcohols has been developed using catalytic amounts of a glucose-derived N-alkanoyl-N-methyl-1-glycamine non-ionic biosurfactant (C12MG). Excellent yields to final products were obtained under mild conditions and the protocol was amenable to both aromatic and long alkyl chain acids (e.g. fatty acids).
- Rajabi, Fatemeh,Luque, Rafael
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p. 5152 - 5155
(2014/01/23)
-
- Synthesis and antifungal activity of 1,3,4-thiadiazole derivatives containing pyridine group
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Some 1,3,4-thiadiazole derivatives containing pyridine group were synthesized. The structures of 1,3,4-thiadiazoles were confirmed by 1H NMR, MS, and elemental analysis. The title compounds were investigated for antifungal activities. The results showed that some of them exhibited good antifungal activity.
- Zhang, Lin-Jiong,Yang, Ming-Yan,Sun, Zhao-Hui,Tan, Cheng-Xia,Weng, Jian-Quan,Wu, Hong-Ke,Liu, Xing-Hai
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p. 1107 - 1111
(2015/04/14)
-
- Synthesis and bioactivities of novel 1,3,4-oxadiazole derivatives containing pyridine moiety
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In this paper, some novel 1,3,4-oxadiazole derivatives containing 4-pyridyl group were synthesized under microwave assistant condition by multi-step reactions. The structures were characterized by 1H NMR, MS and elemental analyses. The target compounds were evaluated for their fungicidal activities, and the results indicated that some of the title compounds displayed good antifungal activities.
- Sun, Guo-Xiang,Shi, Yan-Xia,Sun, Zhao-Hui,Yang, Ming-Yan,Wu, Hong-Ke,Weng, Jian-Quan,Tan, Cheng-Xia,Liu, Xing-Hai,Li, Bao-Ju,Zhang, Yong-Gang
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p. 1119 - 1123
(2015/04/14)
-
- Novel 4′-functionalized 4,4′′-dicarboxyterpyridine ligands for ruthenium complexes: Near-IR sensitization in dye sensitized solar cells
-
Novel ruthenium complexes (MC113-MC117), obtained by modifying the terpyridine ligand of the black dye (N749), have been evaluated as sensitizers for dye sensitized solar cells (DSSCs). The modification is carried out by attaching selected chromophores, with varying electron donating strength, covalently to the central ring of the ligand. The complexes, compared to the parent dye, show red shifted absorption covering visible and near IR regions and higher molar extinction coefficients. We report in this work synthesis of a series of these ruthenium complexes with chromophores such as tert-butyl phenyl, triphenylamine, bithiophene, phenoxazine and phenothiazine. Detailed experimental characterization using optical, electrochemical and photovoltaic techniques has been carried out and complemented by density functional theory studies. The fill factors (ff) obtained for these dyes are larger than those of the parent black dye. In spite of these superior properties, the dyes show only moderate to good power conversion efficiencies. The possible reasons for this have been investigated and discussed.
- Koyyada, Ganesh,Botla, Vinayak,Thogiti, Suresh,Wu, Guohua,Li, Jingzhe,Fang, Xiaqin,Kong, Fantai,Dai, Songyuan,Surukonti, Niveditha,Kotamarthi, Bhanuprakash,Malapaka, Chandrasekharam
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p. 14992 - 15003
(2015/02/19)
-
- BTK INHIBITORS
-
The present invention provides Bruton's Tyrosine Kinase (Btk) inhibitor compounds according to Formula I or a pharmaceutically acceptable salt thereof or to pharmaceutical compositions comprising these compounds and to their use in therapy. In particular, the present invention relates to the use of Btk inhibitor compounds in the treatment of Btk mediated disorders.
- -
-
Page/Page column 129
(2014/08/07)
-
- BTK INHIBITORS
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The present invention provides Bruton's Tyrosine Kinase (Btk) inhibitor compounds according to Formula I or a pharmaceutically acceptable salt thereof or to pharmaceutical compositions comprising these compounds and to their use in therapy. In particular, the present invention relates to the use of Btk inhibitor compounds in the treatment of Btk mediated disorders.
- -
-
Paragraph 0794
(2014/08/06)
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- 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.
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p. 199 - 218
(2014/01/06)
-
- Tuning the photophysical, thermal properties and electronic energy levels in the triphenylamine derivatives by benzoylhydrazone architecture
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A novel of triphenylamine derivatives with more extended π-conjugated systems achieved by benzoylhydrazone architecture were synthesized under mild condition with high yields. The dependence of their photophysical, electrochemistry and thermal properties on their chemical structure is discussed. Compared with the N,N-di(4-methylphenyl)aniline, the thermostability of the five triphenylamine-based hydrozones is dramatically promoted. These compounds are stable up to 345 °C according to thermogravimetric analysis. The energy levels of the four compounds were finely tuned by introducing the electron-donating and -withdrawing groups to the triphenylamine core which are supported by the fluorescence spectra and transit fluorescence spectra of the compounds (-H > -CH3 > -Cl > Pyridine > -NO2). Their multiple cyclic voltammetry study and density functional study suggest these materials to be promising hole-transport properties.
- Liu, Lizeng,Meng, Xianfang,Li, Wei,Zhou, Xueqin,Bai, Zhengchen,Liu, Dongzhi,Lv, Yunrong,Li, Rui-Hong
-
-
- Novel arylhydrazone derivatives bearing a rhodanine moiety: Synthesis and evaluation of their antibacterial activities
-
A series of arylhydrazone derivatives bearing a rhodanine moiety have been synthesized, characterized, and evaluated as antibacterial agents. Some of these compounds showed potent antibacterial activities against several different strains of Gram-positive bacteria, including multidrug-resistant clinical isolates. Of the compounds tested, IIk and IIIk were identified as the most effective, with minimum inhibitory concentration values of 2-4 μg/mL against multidrug-resistant Gram-positive organisms, including methicillin-resistant and quinolone-resistant Staphylococcus aureus. None of the compounds exhibited any activity against the Gram-negative bacteria Escherichia coli 1356 at 64 μg/mL.
- Li, Wei,Zheng, Chang-Ji,Sun, Liang-Peng,Song, Ming-Xia,Wu, Yan,Li, Yin-Jing,Liu, Yi,Piao, Hu-Ri
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p. 852 - 861
(2014/08/05)
-
- Kinetic study on nucleophilic substitution reaction of 5-nitro-8-quinolyl benzoate, picolinate, nicotinate and isonicotinate with alkali metal ethoxide: Effect of nonleaving group on reactivity and transition state structure
-
Pseudo-first-order rate constants (kobsd) have been measured spectrophotometrically for the reactions of 5-nitro-8-quinolyl nicotinate (4) and 5-nitro-8-quinolyl isonicotinate (5) with alkali metal ethoxides (EtOM; M = K, Na and Li) in anhydrous ethanol at 25.0 ± 0.1 °C. The plots of kobsd vs. [EtOM] curve slightly upward for the reactions with EtOK and EtONa but are linear for the reactions with EtOLi and for those with EtOK in the presence of 18-crown-6-ether. Dissection of kobsd into k EtO- and kEtOM (i.e., the second-order rate constants for the reactions with the dissociated EtO- and ion-paired EtOM, respectively) has revealed that the reactivity increases in the order EtO - ≈ EtOLi - EtOK EtONa for the reactions of 5. Comparison of the kinetic results for the reactions of 4 and 5 with those reported previously for the corresponding reactions of 5-nitro-8-quinolyl benzoate (2) and picolinate (3) has revealed that the esters possessing a pyridine ring (i.e., 3-5) are significantly more reactive than the benzoate ester 2 due to the presence of the electronegative N atom (e.g., 2 ? 3 4 5). It has been concluded that M+ ion catalyzes the reactions of 3-5 by increasing the electrophilicity of the reaction center through a five-membered cyclic transition state (TS) for the reaction of 3 and via a four-membered cyclic TS for the reactions of 4 and 5.
- Lee, Jieun,Kim, Min-Young,Um, Ik-Hwan
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p. 1789 - 1793
(2014/07/07)
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- Synthesis, antimycobacterial, antiviral, antimicrobial activity and QSAR studies of N2-acyl isonicotinic acid hydrazide derivatives
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A series of N2-acyl isonicotinic acid hydrazides (1-17) was synthesized and tested for its in vitro antimycobacterial activity against Mycobacterium tuberculosis and the results indicated that the compound, isonicotinic acid N′- tetradecanoyl-hydrazide (12) was more active than the reference compound isoniazid. The results of antimicrobial activity of the synthesized compounds against S. aureus, B. subtilis, E. coli, C. albicans and A. niger indicated that compounds with dichloro, hydroxyl, tri-iodo and N 2 -tetradecanoyl substituent were the most active ones. The antiviral activity studies depicted that none of the tested compounds were active against DNA or RNA viruses. The multi-target QSAR model was found to be effective in describing the antimicrobial activity of N2-acyl isonicotinic acid hydrazides.
- Judge, Vikramjeet,Narasimhan, Balasubramanian,Ahuja, Munish,Sriram, Dharmarajan,Yogeeswari, Perumal,De Clercq, Erik,Pannecouque, Christophe,Balzarini, Jan
-
-
- Novel 1,3,4-oxadiazole thioether derivatives targeting thymidylate synthase as dual anticancer/antimicrobial agents
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A series of novel 1,3,4-oxadiazole thioether derivatives (compounds 9-44) were designed and synthesized as potential inhibitors of thymidylate synthase (TS) and as anticancer agents. The in vitro anticancer activities of these compounds were evaluated against three cancer cell lines by the MTT method. Among all the designed compounds, compound 18 bearing a nitro substituent exhibited more potent in vitro anticancer activities with IC50 values of 0.7 ± 0.2, 30.0 ± 1.2, 18.3 ± 1.4 μM, respectively, which was superior to the positive control. In the further study, it was identified as the most potent inhibitor against two kinds of TS protein (for human TS and Escherichia coli TS, IC50 values: 0.62 and 0.47 μM, respectively) in the TS inhibition assay in vitro and the most potent antibacterial agents with MIC (minimum inhibitory concentrations) of 1.56-3.13 μg/mL against the tested four bacterial strains. Molecular docking and 3D-QSAR study supported that compound 18 can be selected as dual antitumor/antibacterial candidate in the future study.
- Du, Qian-Ru,Li, Dong-Dong,Pi, Ya-Zhou,Li, Jing-Ran,Sun, Jian,Fang, Fei,Zhong, Wei-Qing,Gong, Hai-Bin,Zhu, Hai-Liang
-
p. 2286 - 2297
(2013/05/09)
-
- The dual role of ionic liquid BmimBF4, precursor of N-heterocyclic carbene and solvent, in the oxidative esterification of aldehydes
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Room temperature ionic liquid BmimBF4 (1-butyl-3- methylimidazolium tetrafluoroborate) has been utilized in the N-heterocyclic carbene-catalyzed oxidation of aldehydes to yield esters. In the presence of MnO2 as oxidant and of DBU and caesium carbonate as bases, aromatic, heteroaromatic and aliphatic esters have been isolated in good to excellent yields. The recyclability of the used ionic liquid along with the excess of inorganic reagents has been proved. The simple and cheap BmimBF4 ionic liquid played the dual role of precatalyst and solvent. This is the first time that such a reaction has been carried out with an ionic liquid as solvent.
- Chiarotto, Isabella,Feroci, Marta,Sotgiu, Giovanni,Inesi, Achille
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p. 8088 - 8095
(2013/08/23)
-
- Isonicotinic acid hydrazide derivatives: Synthesis, antimicrobial activity, and QSAR studies
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A series of isonicotinic acid hydrazide derivatives (1-19) was synthesized and tested in vitro for antimycobacterial activity against Mycobacterium tuberculosis and antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans, and Aspergillus niger and the results indicated that the compounds with OH, SCH3, and OCH 3 groups were found to be active against the tested strains. None of the test compounds were active against a broad variety of RNA and DNA viruses at subtoxic concentrations, except 8, that showed some selective anti-reovirus-1 activity. The multi-target QSAR models were found to be effective in predicting the antimicrobial activity of the isoniazid derivatives and indicated the importance of nuclear repulsion energy (Nu.E) in explaining the antimicrobial activity of isoniazid derivatives. The developed QSAR models were validated using the external test set of synthesized derivatives. Springer Science+Business Media, LLC 2011.
- Judge, Vikramjeet,Narasimhan, Balasubramanian,Ahuja, Munish,Sriram, Dharmarajan,Yogeeswari, Perumal,De Clercq, Erik,Pannecouque, Christophe,Balzarini, Jan
-
experimental part
p. 1451 - 1470
(2012/09/22)
-
- Synthesis, antimycobacterial, antiviral, antimicrobial activities, and QSAR studies of isonicotinic acid-1-(substituted phenyl)-ethylidene/cycloheptylidene hydrazides
-
A series of isonicotinic acid-1-(substituted phenyl)-ethylidene/ cycloheptylidene hydrazide derivatives (1-12) was tested for their, in vitro antimycobacterial activity against Mycobacterium tuberculosis, and compound 2 was found to be more active than isoniazid. The antiviral screening results indicated that none of the tested compounds was active against a broad variety of DNA and RNA viruses at subtoxic concentrations, except compounds 8 and 10 that proved to be active against DNA viruses at concentrations close to their cytostatic potential. The synthesized compounds were also screened for their antimicrobial potential against S. aureus, B. subtilis, E. coli, C. albicans and A. niger, and the results indicated that compounds having Br, OCH3 and Cl groups were highly active. The multi-target QSAR models indicated the importance of lipophilic (log P) and topological parameters (3vv) in describing the antimicrobial activity.
- Judge, Vikramjeet,Ahuja, Munish,Narasimhan, Balasubramanian,Sriram, Dharmarajan,Yogeeswari, Perumal,De Clercq, Erik,Pannecouque, Christophe,Balzarini, Jan
-
p. 1935 - 1952,18
(2020/07/30)
-
- Pharmacological screening for anti-inflammatory, analgesic activity of pyrazolyl derivatives along with molecular docking studies
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The pyrazole derivatives were synthesized and pharmacologically evaluated for analgesic (tail flick) and anti-inflammatory (based on carrageenan-induced paw edema) activities. Compound 4k showed high potency as an anti-inflammatory agent after 3 and 4-h time intervals (P0.001) equipotent to indomethacin. They were devoid of ulcerogenic potential when administered at a dose of 30 mg/kg. The compounds, which showed less ulcerogenic action, also showed reduced malondialdehyde content (MDA), which is one of the byproduct of lipid peroxidation. Further docking studies of titled compounds was done to understand key interactions responsible for observed inhibition of COX enzyme. The most active compound 4k was found to have -11.192 kcal/mol, as the free energy of binding. Various other key interactions between the synthesized molecules and active site of COX-2 enzyme, responsible for the obtained pharmacological results were also reported. Most of the active compounds were docked well into the active sites of the receptor. Springer Science+Business Media, LLC 2011.
- Kaushik, Darpan,Kumar, Rajnish,Khan, Suroor Ahmed,Chawla, Gita
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p. 3646 - 3655
(2013/02/23)
-
- Dissection of complex molecular recognition interfaces
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The synthesis of a family of zinc porphyrins and pyridine ligands equipped with peripheral H-bonding functionality has provided access to a wide range of closely related supramolecular complexes featuring between zero and four intramolecular H-bonds. An automated UV/vis titration system was used to characterize 120 different complexes, and these data were used to construct a large of number of different chemical double mutant cycles to quantify the intramolecular H-bonding interactions. The results probe the quantitative structure-activity relationship that governs cooperativity in the assembly of complex molecular recognition interfaces. Specifically, variations in the chemical structures of the complexes have allowed us to change the supramolecular architecture, conformational flexibility, geometric complementarity, the number and nature of the H-bond interactions, and the overall stability of the complex. The free energy contributions from individual H-bonds are additive, and there is remarkably little variation with architecture in the effective molarity for the formation of intramolecular interactions. Intramolecular H-bonds are not observed in complexes where they are geometrically impossible, but there are no cases where excellent geometric complementarity leads to very high affinities. Similarly, changes in conformational flexibility seem to have limited impact on the values of effective molarity (EM). The major variation that was found for all of the 48 intramolecular interactions that were examined using double mutant cycles is that the values of EM for intramolecular carboxylate ester-phenol H-bonds (200 mM) are an order of magnitude larger than those found for phosphonate diester-phenol H-bonds (30 mM). The corresponding intermolecular phosphonate diester-phenol H-bonds are 2 orders of magnitude more stable than carboxylate ester-phenol H-bonds, and the large differences in EM may be due to some kind of compensation effect, where the stronger H-bond is harder to make, because it imposes tighter constraints on the geometry of the complex.
- Hunter, Christopher A.,Misuraca, Maria Cristina,Turega, Simon M.
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supporting information; experimental part
p. 582 - 594
(2011/04/16)
-
- Molecular properties prediction and synthesis of novel 1,3,4-oxadiazole analogues as potent antimicrobial and antitubercular agents
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In the present investigation, a series of 1,5-dimethyl-2-phenyl-4-{[(5- aryl-1,3,4-oxadiazol-2-yl)methyl]amino}-1,2-dihydro-3H-pyrazol-3-one were subjected to molecular properties prediction, drug-likeness by Molinspiration (Molinspiration, 2008) and MolSoft (MolSoft, 2007) software, lipophilicity and solubility parameters using ALOGPS 2.1 program. The compounds followed the Lipinski 'Rule of five' were synthesized for antimicrobial and antitubercular screening as oral bioavailable drugs/leads. Maximum drug-likeness model score (0.95) was found for compound, 4a. All the synthesized compounds were characterized by IR, NMR and mass spectral analysis followed by antimicrobial and antimycobacterial screening. Among the title compounds, compound 4d showed pronounced activity against Mycobacterium tuberculosis H37Rv and isoniazid resistant M. tuberculosis (INHR-TB) with minimum inhibitory concentrations (MICs) 0.78 μM and 1.52 μM, respectively. The compound, 4a showed maximum activity against all bacterial strains with MIC 4-8 μg/mL comparable to standard drug ciprofloxacin, while the compounds, 4e and 4k showed maximum antifungal activity with MIC 8-16 μg/mL less active than standard drug fluconazole.
- Ahsan, Mohamed Jawed,Samy, Jeyabalan Govinda,Khalilullah, Habibullah,Nomani, Md. Shivli,Saraswat, Pankaj,Gaur, Ramakant,Singh, Abhimanyu
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supporting information; experimental part
p. 7246 - 7250
(2012/02/04)
-
- Metal ion catalysis and inhibition in nucleophilic substitution reactions of 4-nitrophenyl nicotinate and isonicotinate with alkali metal ethoxides in anhydrous ethanol
-
A kinetic study is reported on nucleophilic substitution reactions of 4-nitrophenyl nicotinate 5 and isonicotinate 6 with alkali metal ethoxide EtOM (M = K, Na, and Li) in anhydrous ethanol at 25.0 ± 0.1 °C. Plots of pseudofirst- order rate constant kobsd vs. EtOM concentration exhibit upward curvature for the reactions of 5 and 6 with EtOK and EtONa but are almost linear for those with EtOLi. Dissection of kobsd into k EtO- and kEtOM (i.e., the second-order rate constant for the reaction with dissociated EtO- and ion-paired EtOM, respectively) has shown that kEtOK ≥ kEtONa > k EtO- but kEtOLi EtO -. It has been concluded that K+ and Na+ ions catalyze the reactions by increasing the electrophilicity of the carbonyl carbon atom through formation of a 4- embered cyclic transition state TS3 or TS4. However, M+ ion catalysis has been found to be much less significant for the reactions of 5 and 6 than for the corresponding reactions of 4-nitrophenyl picolinate 4, which was reported to proceed through a 5-membered cyclic transition state TS2. Although 5 and 6 are significantly more reactive than 4-nitrophenyl benzoate 3, the reactions of 5 and 6 result in smaller kEtOK/kEtO- ratios than those of 3. The electron-withdrawing ability of the nitrogen atom in the acyl moiety of 5 and 6 has been suggested to be responsible for the increase in reactivity and the decrease in the kEtOK/kEtO- ratio.
- Choi, Seo-Young,Hong, Yeon-Ju,Um, Ik-Hwan
-
experimental part
p. 1951 - 1956
(2012/02/05)
-
- N'-[(5-chloro-3-methyl-1-phenyl-1H-pyrazol-4-yl)methylene] 2/4-substituted hydrazides: Synthesis and anticonvulsant activity
-
A series of N'-[(5-chloro-3-methyl-1-phenyl-1H-pyrazol-4-yl)methylene] 2/4-substituted hydrazides were synthesized using appropriate synthetic route and characterized by elemental analysis and spectral data. The anticonvulsant activity of some of the synthesized compounds were evaluated against maximal electroshock induced seizure (MES) and subcutaneous pentylenetetrazol (scPTZ) induced seizure models in mice. The neurotoxicity were assessed using the rotorod method. All the test compounds were administered at doses of 30, 100, and 300 mg/kg body weight and the anticonvulsant activity was noted at 0.5 and 4 h time intervals after the drug administration. Among the compound tested, all except 5g showed protection from seizures in both the animal models. Some titled compounds exhibited lesser CNS depression and neurotoxicity compared to phenytoin. A series of substituted hydrazide derivatives were synthesized, evaluated for their anticonvulsant potency in two animal models along with behavioural and neurotoxicity screen and also subjected to computational parameters.
- Kaushik, Darpan,Khan, Suroor Ahmad,Chawla, Gita,Kumar, Suresh
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experimental part
p. 3943 - 3949
(2010/09/11)
-
- Design & synthesis of 2-(substituted aryloxy)-5-(substituted benzylidene)-3-phenyl-2,5-dihydro-1H-[1,2,4] triazin-6-one as potential anticonvulsant agents
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A series of 2-(substituted aryloxy)-5-(substituted benzylidene)-3-phenyl-2, 5-dihydro-1H-[1,2,4] triazin-6-one were designed & synthesized using appropriate synthetic route keeping in view the structural requirement of pharmacophore and evaluated for anticonvulsant activity and CNS activities. After intraperitoneal injection to mice, some synthesized derivatives were examined in the maximal electroshock seizure (MES) and subcutaneous pentylenetetrazol (scPTZ) induced seizure and neurotoxicity screens. Those found potent were also evaluated for behavioural impairment and depression activity. Among the compound tested, 5 eIX showed protection from seizures in both the animal models at dose level of 30 mg/kg while 5 bII & 5 cII showed protection against scPTZ model at same dose level. Some titled compounds exhibited lesser CNS depression and neurotoxicity compared to clinically effective drug. A series of substituted [1,2,4] triazin-6-one derivatives were synthesized, evaluated for their anticonvulsant potency on two animal models along with CNS activity and neurotoxicity and also subjected to computational parameter.
- Kaushik, Darpan,Khan, Suroor Ahmad,Chawla, Gita
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experimental part
p. 3960 - 3969
(2010/09/11)
-
- Development and assessment of green synthesis of hydrazides
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An expeditious, solvent free one pot method for the preparation of hydrazides from corresponding acids directly under microwave irradiation is developed. The method has been assessed using green chemistry measures and found superior to conventional method with higher E(environmental) factor, atom economy, atom efficiency, carbon efficiency, reaction mass efficiency.
- Saha, Ajoy,Kumar, Rajesh,Kumar, Rajendra,Devakumar
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experimental part
p. 526 - 531
(2010/10/03)
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- Formation of HoIII trinuclear clusters and GdIII monodimensional polymers induced by ortho and para regioisomers of pyridyl-functionalised a-diketones: Synthesis, structure, and magnetic properties
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Reaction of GdCl3(H2O)6 and 1,3-bis(pyridin-4-yl)propane-1,3-dione in methanol with an excess of triethylamine produced a monodimensional polymeric chain [Gd(p-dppd) 3-(H2O)]∞, whereas treatment of HoCl 3(H2O)6 with 1,3-bis(pyridin-2-yl)propane-1,3- dione yielded a trinuclear cluster [Ho3(o-dppd) 3(μ3-OH)2(H2O)4Cl 2]Cl2. The compounds were characterised by elemental analysis, IR spectroscopy and magnetism, and their structures were investigated by X-ray crystallography. The 8.20-μB magnetic-moment value of the polymeric [Gd(p-dppd)3(H2O)]∞, between 300 and 20 K, and the magnetisation isotherms (2-20 K; fields 0-5 T), are in agreement with essentially uncoupled single-ion Gd3+ f7 centres, a small decrease in μeff below 20 K being indicative of zero-field splitting. A temperature-dependent dc-susceptibility and magnetisation investigation of the trinuclear (tri-angular) [Ho 3(o-dppd)3(μ3-OH)2(H 2O)4Cl2]Cl2 revealed that spin-orbit and ligand-field effects on the Ho3+ centres, leading to thermal depopulation of Zeeman levels and consequent decreases in μeff values with decreasing temperature, are occurring rather than weak intra-cluster antiferromagnetic coupling. Frequency- and temperature-dependent acsusceptibility studies on this homometallic Ho3+ cluster did not show clear evidence for slow magnetisation reversal, characteristic of single-molecule magnetism (SMM), and this contrasts with such behaviour recently reported, elsewhere, for a Dy3+ triangle having the same core structure but with different chelating {O,O} ligands. Wiley-VCH Verlag GmbH & Co. KGaA, 2009.
- Andrews, Philip C.,Deacon, Glen B.,Frank, Rene,Fraser, Benjamin H.,Junk, Peter C.,MacLellan, Jonathan G.,Massi, Miliano,Moubaraki, Boujemaa,Murray, Keith S.,Silberstein, Morry
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experimental part
p. 744 - 751
(2009/06/05)
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