68226-07-3Relevant academic research and scientific papers
Synthesis, spectral and structural studies of alkyl 2-(3-alkyl-2,6-diarylpiperidin-4-ylidene)hydrazinecarboxylate derivatives: Crystal and molecular structure of methyl 2-(3-methyl-2,6-diphenylpiperidin-4-ylidene)hydrazinecarboxylate
Udhaya Kumar,Sethukumar,Velayutham Pillai,Arul Prakasam,Ramalingan,Vidhyasagar
, p. 45 - 52 (2016)
An efficient synthetic route with good overall yields to synthesize alkyl 2-(3-alkyl-2,6-diarylpiperidin-4-ylidene)hydrazinecarboxylates (7-14) is reported. All the synthesized compounds were characterized by their analytical and spectral (IR, 1H, 13C and 2D NMR) data. Single crystal X-ray structural analysis of compound 7, evidences that the configuration about C=N double bond is syn to C5 carbon (E-form) and exists in normal chair conformation with equatorial orientations of all the substituents.
Synthesis, characterization and antitumor activities of some novel thiazinones and thiosemicarbazones derivatives
Anand, Selvam Athavan Alias,George, Kiran,Thomas, Nisha Susan,Kabilan, Senthamaraikannan
supporting information, p. 821 - 829 (2020/05/22)
Two series of thiazinone and thiosemicarbazone derivatives (1-12) were synthesized using 2,4-diaryl-3-azabicyclo[3.3.1]nonan-9-ones (ABNs) and 3–alkyl–2,6–diarylpiperidin–4–ones as the starting materials. The structures of newly synthesized compounds were established on the basis of FT–IR, NMR spectroscopy and mass spectrometry. From the spectroscopic data, we identified that the cyclization reaction of thioamide with dialkyl acetylenedicarboxylate selectively gives six membered methyl 2-(2-(2,4-disubstituted-3-azabicyclo[3.3.1]nonan-9-ylidene)hydrazinyl)-4-oxo-4H-1,3-thiazine-6-carboxylates (1-6). In order to investigate the antitumor activities of the synthesized compounds, in?vitro cytotoxicity studies were carried out using human prostate cancer cell lines. Tested compounds showed good/moderate activities against cancer cell lines and further investigation carried out by live/dead assay.
Stereoselective synthesis and spectral studies of some benzotriazolylacetyl hydrazones of 3–alkyl–2,6–diarylpiperidin–4–ones
Pillai, M. Velayutham,Rajeswari,Kumar, C. Udhaya,Krishnan, K. Gokula,Mahendran,Ramalingan,Nagarajan,Vidhyasagar
, p. 558 - 565 (2017/09/19)
An effort to include biologically potent benzotriazole nucleus into piperidine ring is achieved through hydrazone formation. The characterization of the synthesized compounds was carried out using FT-IR, 1H &13C NMR, 1H–1H COSY, 1H–13C COSY, NOESY spectral techniques and GC-Mass spectrum. The spectral assignments were done without ambiguity using 2D-NMR techniques. The conformational preference of the piperidine ring deduced from the spectral studies is ‘chair’. The diastereotopic nature of the methylene protons/methyl groups present in the molecules is revealed clearly in their spectral pattern observed.
Stereoselective synthesis, spectral and antimicrobial studies of some cyanoacetyl hydrazones of 3-alkyl-2,6-diarylpiperidin-4-ones
Velayutham Pillai,Rajeswari,Vidhyasagar
, p. 174 - 182 (2015/02/19)
A series of novel cyanoacetyl hydrazones of 3-alkyl-2,6-diarylpiperidin-4-ones were synthesized stereoselectively and characterized by IR, Mass, 1H NMR, 13C NMR, 1H-1H COSY and 1H-13C COSY spectra. The stereochemistry of the synthesized compounds was established using NMR spectra. Antimicrobial screening of the synthesized compounds revealed their antibacterial and antifungal potencies. Growth inhibition of Enterobacter Aerogenes by compound 15 was found to be superior to the standard drug.
Synthesis, spectral and antimicrobial evaluation of some novel 1-methyl-3-alkyl-2,6-diphenylpiperidin-4-one oxime carbonates
Sivakumar, Rajamanickam,Gokula Krishnan, Kannan,Thanikachalam, Venugopal
, p. 3195 - 3199 (2013/06/27)
Synthesis of some novel biologically active piperidin-4-one oxime carbonates from 1-methyl-3alkyl-2,6-diphenylpiperidin-4-one oximes and substituted chloroformates was carried out in the presence of potassium carbonate as base and tetrabutylammonium bromide (TBAB) as catalyst. The newly synthesized compounds were characterized by IR, 1H, 13C NMR and LC-mass spectra. Based on the 1H NMR analysis, all the compounds were found to adopt normal chair conformation with equatorial orientation of all the substituents. For all the synthesized compounds (5a-5l) antimicrobial activity has been tested against bacterial and fungal strains using Streptomycin and Amphotericin B as standards.
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 of polyfunctionalized piperidone oxime ethers and their cytotoxicity on HeLa cells
Parthiban, Paramasivam,Pallela, Ramjee,Kim, Se-Kwon,Park, Dong Ho,Jeong, Yeon Tae
scheme or table, p. 6678 - 6686 (2011/12/04)
A series of twenty 2,6-diarylpiperidin-4-one O-methyloximes were synthesized with fluoro/chloro/bromo/methyl/methoxy/ethoxy/isopropyl substituents on various positions of the phenyl at C-2 and C-6 in association with/without methyl substituent on the seco
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.
Kinetics of oxidation of heterocyclic secondary alcohols by N-chloro-r-2,c-6-diphenyl-t-3 methyl piperidin-4-one (NCP) in perchloric acid medium
Selvaraj,Venkateswaran,Ramarajan
, p. 847 - 855 (2007/10/03)
An investigation of the kinetics of oxidation of epimeric piperidin-4-ols, oxan-4-ols, and cyclohexanol by N-chloro-r-2, c-6-diphenyl-t-3-methylpiperidin-4-one (NCP) in aqueous acetic acid in the presence of perchloric acid shows that the reaction is first-order each in substrate and oxidant. Both H3O+ and Cl- which catalyze the reaction, exhibit a fractional order kinetics. While increase in ionic strength increases the rate slightly, an inverse dependence is observed between rate and solvent polarity. Addition of r-2-c-6-diphenyl-t-3-methylpiperidin-4-one, one of the reaction products, did not influence the rate. Also, no kinetic isotope effect has been observed. A plausible mechanism consistent with these observations is proposed and the relative reactivities of the substrates are explained on conformational grounds.
Unsymmetrical Distortion in Piperidine Ring: Evidence from Rates of N-Methylation of Piperidines and Piperidin-4-ones
Jeyaraman, R.,Chandrasekaran, L.,Ganapathy, K.,Gopalakrishnan, V.
, p. 695 - 697 (2007/10/02)
The rates of N-methylation of several 2,6-diphenylpiperidin-4-ones (1a-e) and the corresponding piperidines (2a-e) with methyl iodide under second order conditions, show that a large distortion occurs at the site of methylation, i.e. the nitrogen atom as substituents at C-3 and C-5 are changed from H to alkyl groups.The greatest distortion is observed in the case of 3,3-dimethyl derivatives which react about 3 to 5 times faster than the 3-methyl derivatives which show the lowest rate constants among the series studied.Thus an axial 3-methyl substituent enhances the rate of N-methylation indicating unsymmetrical distortion in the ring with possible flattening around C(2)-N-C(6) atoms.
