5554-56-3Relevant academic research and scientific papers
COMPOUNDS USEFUL AGAINST KINETOPLASTIDEAE PARASITES
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, (2012/09/05)
Dibenzylidene and heterobenzylideneacetone derivatives, related 4-piperidones, related 4-thiopyranones and the corresponding sulfinyl- and sulfonyl-analogues for their use for prophylaxis or treatment of trypanosomiasis and leishmaniasis.
Oxidative deoximation of N-methyl-2,6-diphenyl piperidin-4-one oxime and its 3-alkyl derivatives by acid dichromate
Santhi
scheme or table, p. 2529 - 2532 (2012/08/27)
Kinetics of oxidation of N-methyl-2,6-diphenyl piperidin-4-one and its 3-alkyl substituted derivatives by acid dichromate has been studied in aqueous acetic acid medium. The oxidation is first order with respect to [oxidant] and [substrate]. The reactions are acid catalyzed. Ionic strength has no appreciable effect on the reaction rate. The reaction rate decreases with decrease in the dielectric strength of the medium indicating a polar mechanism. The reactions followed at four different temperatures and the activation parameters computed. Based on the results obtained a suitable mechanism is proposed. The reactivity sequence is found to be 1,3,5-trimethyl PPO > 1-methyl PPO > 1,3-dimethyl PPO > 1-methyl-3-ethyl PPO > 1-methyl-3-isopropyl PPO.
Convenient synthesis and NMR spectral studies of variously substituted N-methylpiperidin-4-one-O-benzyloximes
Parthiban, Paramasivam,Rani, Mannangatty,Kabilan, Senthamaraikannan
experimental part, p. 287 - 301 (2010/04/26)
A series of variously substituted N-methylpiperidin-4-one-O-benzyloximes were synthesized by three different methods. Among them, the direct conversion of 2,6-diarylpiperidin-4-ones into the corresponding oxime ethers (method A) was proved to be better than the other two methods in the sense of good yield, convenience, easy work-up and quick reaction time. All the synthesized compounds are characterized by IR, Mass and NMR (1H NMR, 13C NMR, 1H-1H COSY, 1H-13C COSY and HMBC) spectral studies. The conformational preference of the synthesized oxime ethers with/without alkyl and aryl substituents at C-3/C-5 and C-2/C-6 is discussed using the spectral data. The observed chemical shifts and coupling constants suggest that the synthesized oxime ethers adopt chair conformation with equatorial orientation of all the substituents, whereas 1-methyl-3-isopropyl-2, 6-diphenylpiperidin-4-one-O-benzyloxime also exists in boat conformation. Based on the NMR data, the effects of oximination on ring carbons and their associated protons and alkyl substituents are discussed. In addition, the effect of NMe group on the 2,6-diarylpiperidin-4-one-O-benzyloximes was also studied.
An efficient synthesis of new pyrido[4′,3′:4,5]thieno[2,3-d]- pyrimidin-4(3H)-one derivatives
Zeng, Guo-Ping,Hu, Yang-Gen,Ding, Ming-Wu
scheme or table, p. 1809 - 1813 (2009/05/31)
(Chemical Equation Presented) The carbodiimides 5, obtained from reactions of iminophosphorane 4 with aromatic isocyanates, reacted with amines, phenols or ROH to give 2-substituted 5,6,7,8-tetrahydropyrido[4′,3′:4,5] thieno[2,3-d]-pyrimidin-4(3H)-one 7 i
Synthesis, stereochemistry, and?antimicrobial evaluation of?substituted piperidin-4-one?oxime ethers
Ramalingan,Park,Kabilan
, p. 683 - 696 (2007/10/03)
In a wide search program toward new and efficient antimicrobial agents, a series of substituted piperidin-4-one oxime ethers (5a-5k) was synthesized and tested for their in vitro antibacterial and antifungal activities. Also, the structures of these oxime ethers and their relative stereochemistries have been investigated by nuclear magnetic resonance spectroscopy. In all the oxime ethers synthesized, the orientation of the N-O bond of the oxime ether moiety syn to C-5 (E-isomer) was deduced based on 1H NMR and 13C NMR spectra. It was found that the sterically less hindered compounds, either C-3 (H) and C-5 (H)- or C-3 (Me) and C-5 (H) -substituted ones 5a, 5c, 5d, 5f, 5g, 5i and 5j prefer chair conformation, whereas the sterically more hindered C-3 (Me) and C-5 (Me) -substituted ones 5b, 5e, 5h, and 5k prefer twist-boat conformation. Among the oxime ethers tested, 1,3,5-trimethyl-2,6-diphenylpiperidin-4-one O-(2-chlorophenylmethyl)oxime (5h) exhibited good antibacterial property against Bacillus subtilis, with minimum inhibitory concentration (MIC) closer to that of reference drug, streptomycin. Compounds, 1,3-dimethyl-2,6-diphenylpiperidin-4-one O-(2-chlorophenylmethyl)oxime (5g) and 1,3-dimethyl-2,6-diphenylpiperidin-4-one O-(2-bromophenylmethyl)oxime (5j) showed potent antifungal activity against Aspergillus flavus and Candida-51, respectively. The later compound 5j is more active than the reference drug while the activity of the former one 5g is similar to that of the reference drug, amphotericin B in terms of MIC. The present results may be used as key steps for the construction of novel chemical entities with better pharmacological profiles than standard drugs.
Activation of NFκB is inhibited by curcumin and related enones
Weber, Waylon M.,Hunsaker, Lucy A.,Roybal, C. Nathaniel,Bobrovnikova-Marjon, Ekaterina V.,Abcouwer, Steve F.,Royer, Robert E.,Deck, Lorraine M.,Vander Jagt, David L.
, p. 2450 - 2461 (2007/10/03)
The transcription factor NFkappaB (NFκB) is up-regulated in many cancer cells where it contributes to development of the pro-survival, anti-apoptotic state. The natural product curcumin is a known inhibitor of activation of NFκB. Enone analogues of curcumin were compared with curcumin for their abilities to inhibit the TNFα-induced activation of NFκB, using the Panomics' NFκB Reporter Stable Cell Line. The enones tested included curcumin analogues that retained the 7-carbon spacer between the aromatic rings, analogues with a 5-carbon spacer, and analogues with a 3-carbon spacer. Inhibitors of NFκB activation were identified in all three series, a number of which were more active than curcumin. Enone analogues in the series with the 5-carbon spacer were especially active, including members that contained heterocyclic rings. 1,5-Bis(3-pyridyl)-1,4-pentadien-3-one was the most active analogue, IC50 = 3.4 ± 0.2 μM. The most active analogues retain the enone functionality, although some analogues devoid of the enone functionality exhibited activity. The activity of the analogues as inhibitors of the activation of NFκB did not correlate with their anti-oxidant activity. The data suggest that the abilities of curcumin and analogues to prevent the stress-induced activation of NFκB result from the inhibition of specific targets rather than from activity as anti-oxidants.
Synthesis and study of antibacterial and antifungal activities of novel 8-methyl-7,9-diaryl-1,2,4,8-tetraazaspiro[4.5]decan-3-thiones
Balasubramanian,Ramalingan,Aridoss,Kabilan
, p. 694 - 700 (2007/10/03)
Some novel spiropiperidinyl-1,2,4-triazolidin-3-thiones have been synthesized and studied for their antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa and antifungal activity against Candida albicans, Candida-6, Candida-51, Aspergillus niger and Aspergillus flavus. Compounds 30-32 exhibited potent in vitro antibacterial activity against E. coli and P. aeruginosa whereas the same set of compounds exerted potent in vitro antifungal activity against Candida-6, A. niger and A. flavus.
