Piperidine-4-ones, Synthesis of derivatives, biological activities
T1 - Synthesis and properties of N-(2-ethoxyethyl) piperidine derivatives of anabasine
Thieme E-Books & E-Journals - Synthesis / Issue
Ko JH, Yeon SW, Ryu JS, Kim TY, Song EH,You HJ, Park RE and Ryu CK: Synthesis and biological evaluation of5-arylamino-6-chloro-1H-indazole-4,7-diones as inhibitors ofprotein kinase B/Akt. Bioorg Med Chem Lett. 16:6001–6005. 2006. : :
A number of piperidin 4-ones have been obtained from acetonedicarboxylic acid and its esters 36-38 (Scheme 8). The 2, 6 dimethylpiperidine -4-ones obtained from the ester was subsequently converted to keto the N-methyl and N-ethyl derivatives by treatement with methyl and ethyl p-toluene sulfonates38
Synthesis of piperidine-4-ones: ..
Ethyl acetoacetate and ethyllevulinate have also been employed as the ketone component for the synthesis of piperidine-4-ones (Scheme 7a) 13, 31-34. With ethyl acetoacetate, aromatic aldehyde gave piperidine-4-ones while with aliphatic aldehydes, 1,4-dihydropyridines has been obtained. (Scheme 7b). Treatment of ethyl acetoacetate with benzaldehyde and aniline in absolute ethanol in presence of malonic acid gave ethyl1,2,6-triphenyl-4-oxo-piperidine-3-carboxylate 18, 35. Hydrolysis of the ester with 10% HCl in acetone gave 1,2,6-triphenylpiperidine-4-one.
Though salicylaldehyde and substituted salicyl-aldehydes were reported to react with ketones and ammonia to form piperidine-4-ones 37, 38, 39. Baliah et al., have established 40 with IR, NMR and Mass spectral data that the products are substituted benzopyrans and not piperidine-4-ones.
Piperidine For Synthesis - Thomas Sci
In the absence of sulfur the piperidin -4-ones was not formed, only the imine formed and the diethyl ketone remained unchanged 30. In similar experiments, butane-2-one, heptanes-4-one, and dibenzyl ketone were employed. These ketones do not give piperidine-4-ones in the presence of sulfur but give them in the presence of NH4SCN 30 (Scheme 6)
Stereoselective synthesis of piperidine-4-ones: Reviews updating progress in the stereo selective synthesis of substituted piperidines have appeared recently 41. 2,3 –dihydro-4-pyridones were utilized in the synthesis of numerous alkaloids due to the variety of stereo controlled functionalizations that were possible 42. 2-substitued –N-acyl-2,3dihydro-4-pyridones were prepared in an enantiomerically pure state by the stereoselctive addition of organomettailc reagents and metallenolates to chiral 1acylpyridinium salts 43.
Piperidine For Synthesis, 23 L Pkg
Pyrrolidine synthesis - Organic chemistry
T1 - Synthesis and structure-activity relationship of piperidine-derived non-urea soluble epoxide hydrolase inhibitors
Pyrrole, pyrrolidine, pyridine, piperidine and tropane alkaloids
A REVIEW ON THE SYNTHESIS AND BIOLOGICAL ACTIVITIES OF PIPERIDIN-4-ONES
pyridine, piperidine and tropane alkaloids
Acetonedicarboxilic acid and its esters gave two geometric isomers of piperidine-4-ones14.
Synthesis of carbon-11-labeled piperidine ring of N- ..
When ammonia passed into a mixture of benzaldehyde and diethyl ketone containing a little sulphur, a vigorous exothermic reaction occurred leading to the formation of 2, 6-diphenyl-3, 5-dimethylpiperidine-4-one (Scheme 5) in good yield 30.
piperidine derivatives of anabasine
3, 5 –Disubstitued piperidine-4-ones (Scheme 4) were formed when both symmetric and unsymmetrical aliphatic ketones were employed 8, 28, 29.
The First Total Synthesis of Dragmacidin D - Journal of …
Intra molecular Processes: The intramolecular Mannich reaction is a powerful tool for the rapid, efficient, highly stereo selective assembly of polysubstitued piperidones. Sulfinyl amines served as asymmetric precursors to δ-amino-β ketoesters44. Treatement with excess trifluroacetic acid removed the sulfinyl group and the released chiral amine salt was then reacted with an aldehyde or ketone giving polysubstitued piperidone. The Major isomer shown to have the C-2 and C-6 substituents in a cis –orientation with the C-2 and C-3 substituents trans. For aldehydes, nearly exclusive formation of the 2,6-cis-disubstitued piperidone was consistent with transition state. Decarboxylation was effected with 48% HBr in methanol. Some erosion of chirality was noted and was attributed to a retro-Mannich reaction. Disubstitued -4-piperidones serve as an important buiding block for piperidine alkaloid synthesis.
Use of Bromine and Bromo-Organic Compounds in …
Only aromatic aldehydes undergo this modified reaction.3-alkyl-pipeidin-4-ones (Scheme 3) have been obtained by employing alkyl methyl ketones with varying chain length 4. The cyclocondensation of benzyl methyl ketone with benzaldehyde and methylamine gave 2, 3, 6-triphenylpiperidine-4-one (Scheme 3).
International Journal of Organic Chemistry - SCIRP
Introduction of Chloroacetyl 47a, Morpholinoacetyl 47b, N-methylipiperazinoacetyl 47c or benzazoylethoxy 47 d-f moiety at nitrogen ring displayed enhanced antibacterial and antifungal activities.
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