5554-59-6Relevant articles and documents
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.
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.
cis-2,6-Diphenyl-4-piperidones and Their Derivatives : A PMR Spectral Study
Sivasubramanian, S.,Sundharavadivelu, M.,Arumugam, N.
, p. 878 - 879 (2007/10/02)
In addition to the expected features, the PMR spectra of cis-2e,6e-diphenyl-4-piperidones and their N-methyl derivatives show unusually broad aromatic proton signals with concurrent multiplicity.This characteristic broadening and multiplicity of the aroma
