- Enantioselective copper catalysed C-H insertion reaction of 2-sulfonyl-2-diazoacetamides to form γ-lactams
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The first examples of asymmetric copper-catalysed intramolecular C-H insertion reactions of 2-sulfonyl-2-diazoacetamides are described; trans γ-lactams with up to 82% ee are achieved with the CuCl2-bisoxazoline-NaBARF catalyst system. The reactions generally display high efficiency and high trans selectivity, and also a strong regiochemical preference for insertion to lead to the formation of 5-membered rings over 4-membered rings. In cases where there are competing C-H insertion pathways available, to form sulfolanes or thiopyrans, only the insertion into the amide chain to form γ-lactams is observed. With phenylsulfonyl derivatives, a minor competing C-H insertion pathway leading to β-lactams is seen; interestingly, changing the identity of the copper ligand changes the product ratio of β/γ-lactams. The copper catalysed reactions compare favorably in terms of efficiency and enantioselectivity to the corresponding reactions catalysed by commercially available chiral rhodium catalysts.
- Clarke, Leslie Ann,Ring, Aoife,Ford, Alan,Sinha, Abhijeet S.,Lawrence, Simon E.,Maguire, Anita R.
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p. 7612 - 7628
(2015/02/18)
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- Design, synthesis and evaluation of novel quinazoline-2,4-dione derivatives as chitin synthase inhibitors and antifungal agents
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A series of novel 1-methyl-3-substituted quinazoline-2,4-dione derivatives were designed, synthesized, and characterized by 1H NMR, 13C NMR and MS spectral data. Their inhibition against chitin synthase (CHS) and antifungal activities were evaluated in vitro. Results showed compounds 5b, 5c, 5e, 5f, 5j, 5k, 5l, and 5o had strong inhibitory potency against CHS. Compound 5c, which has the highest potency among these compounds, had a half-inhibition concentration (IC50) of 0.08 mmol/L, while polyoxin B as positive drug had IC50 of 0.18 mmol/L. These IC 50 values of compounds 5i, 5m, 5n, and 5s were greater than 0.75 mmol/L, which revealed that those compounds had weak inhibition activity against CHS. Moreover, most of these compounds exhibited moderate to excellent antifungal activities. In detail, to Candida albicans, the activities of compound 5g and 5k were 8-fold stronger than that of fluconazole and 4-fold stronger than that of polyoxin B; to Aspergillus flavus, the activities of 5g, 5l and 5o were16-fold stronger than that of fluconazole and 8-fold stronger than that of polyoxin B; to Cryptococcus neoformans, the minimum-inhibition- concentration (MIC) values of compounds 5c, 5d, 5e and 5l were comparable to those of fluconazole and polyoxin B. The antifungal activities of these compounds were positively correlated to their IC50 values against CHS. Furthermore, these compounds had negligible actions to bacteria. Therefore, these compounds were promising selective antifungal agents.
- Ji, Qinggang,Yang, Dan,Wang, Xin,Chen, Chunyan,Deng, Qiao,Ge, Zhiqiang,Yuan, Lvjiang,Yang, Xiaolan,Liao, Fei
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p. 3405 - 3413
(2014/06/23)
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- Synthesis, pharmacology and?molecular modeling of?N-substituted 2-phenyl-indoles and?benzimidazoles as?potent GABAA agonists
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Among the known non-benzodiazepine hypnotic drugs, Zolpidem (1a), Indiplon (2a) and Zaleplon (2b) have shown high affinity and selectivity for the α1 subunit of the GABA-A receptor. Our group has performed pharmacophoric and ADMET-prediction studies to evaluate a virtual library of new molecules based on privileged structures. Among these, we have synthesized a library of N-substituted indoles and a library of N-substituted benzimidazoles. Afterwards, in vitro screening and in vivo spontaneous motor activity in mice has revealed molecules with good in vitro affinities for the α1 receptor and potent in vivo induction of sedation.
- Falcó, José Luis,Piqué, Maria,González, Miguel,Buira, Irma,Méndez, Eva,Terencio, Jose,Pérez, Cristina,Príncep, Marta,Palomer, Albert,Guglietta, Antonio
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p. 985 - 990
(2007/10/03)
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- A general method for the synthesis of N,N-dialkylaminobutylamines
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A general method for the synthesis of N,N-dialkylaminobutylamines 4 from readily available chloroacetamides 6 is described.
- Seguin, Helene,Gardette, Daniel,Moreau, Marie-France,Madelmont, Jean-Claude,Gramain, Jean-Claude
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p. 4257 - 4272
(2007/10/03)
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- Synthesis of Dibenzocrown Ethers with Pendent Amide Groups
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Synthetic routes to twenty six crown ether compounds with pendent amide, N-alkylamide, or N,N-dialkylamide groups are reported.The new crown ether compounds are based on sym-dibenzo-16-crown-5-oxyacetamide and sym-(propyl)-dibenzo-16-crown-5-oxyacetamide and are obtained in high yields.
- Kasprzyk, Stanislaw P.,Bartsch, Richard A.
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p. 119 - 123
(2007/10/02)
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- Evaluation of glycolamide esters and various other esters of aspirin as true aspirin prodrugs
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A series of glycolamide, glycolate, (acyloxy)methyl, alkyl, and aryl esters of acetylsalicylic acid (aspirin) were synthesized and evaluated as potential prodrug forms of aspirin. N,N-Disubstituted glycolamide esters were found to be rapidly hydrolized in human plasma, resulting in the formation of aspirin as well as the corresponding salicylate esters. These in turn hydrolyzed rapidly to salicylic acid. The largest amount of aspirin formed from the esters were 50 and 55% in case of the N,N-dimethyl- and N,N-diethylglycolamide esters, respectively. Similar results were obtained in blood with the N,N-dimethyl- and N,N-diethylglycolamide esters. Unsubstituted and monosubstituted glycolamide esters as well as most other esters previously suggested to be aspirin prodrugs were shown to hydrolyze exclusively to the corresponding salicylic acid esters. Lipophilicity parameters and water solubilities of the esters were determined, and structural factors favoring ester prodrug hydrolysis at the expense of deacetylation to yield salicylate ester are discussed. The properties of some N,N-disubstituted glycolamide esters of aspirin are highlighted with respect to their use as potential aspirin prodrugs.
- Nielsen,Bundgaard
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p. 727 - 734
(2007/10/02)
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- Amide phosphorothiolate herbicides
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The present invention relates to new herbicidal phosphorothioate (phosphorodithioate) derivatives and to preparation thereof.
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