A facile synthesis and antimycobacterial evaluation of novel spiro-pyrido-pyrrolizines and pyrrolidines
摘要:
An efficient synthesis of 1-methyl-3-[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones was achieved by the reaction of 1-methyl-4-piperidone and aromatic aldehydes in the presence of pyrrolidine under solvent-free microwave irradiation. These dipolarophiles upon cycloaddition with nitrile oxide and azomethine ylides afford stereoselectively novel spiro-isoxazolines, pyrrolizines and pyrrolidines respectively in excellent yields. The spiro compounds were screened for their in vitro activity against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant M. tuberculosis (MDR-TB) and Mycobacterium smegmatis (MC2) using agar dilution method. Among the synthesized compounds, 1-methyl-4-(2,4-dichlorophenyl)pyrrolo(spiro[2.3 '']oxindole)spiro[3.3']-1'-methylpiperidin-4'-one was found to be the most active with a minimum inhibitory concentration (MIC) of 1.76 and 0.88 mu M against MTB and MDR-TB respectively. (C) 2009 Elsevier Masson SAS. All rights reserved.
An efficient method for the facile synthesis of (E)-monoarylidene derivatives of homo- and heterocyclic ketones with various aldehydes in the presence of a pyrrolidine organocatalyst has been achieved. A range of α,β-unsaturated ketones were obtained in moderate to high yields (up to 99%). Unlike the Claisen-Schmidt condensation process, the formation of undesired bisarylidene byproducts is not observed. The possible reaction mechanism suggests that the reaction proceeds via a Mannich-elimination sequence.
An efficient synthesis of 1-methyl-3-[(E)-arylmethylidene]tetrahydro-4(1H)-pyridinones was achieved by the reaction of 1-methyl-4-piperidone and aromatic aldehydes in the presence of pyrrolidine under solvent-free microwave irradiation. These dipolarophiles upon cycloaddition with nitrile oxide and azomethine ylides afford stereoselectively novel spiro-isoxazolines, pyrrolizines and pyrrolidines respectively in excellent yields. The spiro compounds were screened for their in vitro activity against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant M. tuberculosis (MDR-TB) and Mycobacterium smegmatis (MC2) using agar dilution method. Among the synthesized compounds, 1-methyl-4-(2,4-dichlorophenyl)pyrrolo(spiro[2.3 '']oxindole)spiro[3.3']-1'-methylpiperidin-4'-one was found to be the most active with a minimum inhibitory concentration (MIC) of 1.76 and 0.88 mu M against MTB and MDR-TB respectively. (C) 2009 Elsevier Masson SAS. All rights reserved.
Green synthesis of dissymmetric bisarylidene derivatives of cyclohexanone analogues under ultrasonic conditions
作者:Mohammad M. Mojtahedi、Leila Afshinpoor、Fatemeh Karimi、M. Saeed Abaee
DOI:10.1007/s13738-018-1498-5
日期:2019.2
AbstractA new procedure is developed for the synthesis of dissymmetric bisarylidene derivatives of two cyclohexanone analogues. Under mild ultrasonic/organocatalytic conditions, the first aldehyde reacts with the ketone to give the monoarylidene intermediate which subsequently condenses with the second aldehyde upon addition of NaOH/MeOH to the reaction mixture. Both condensations proceed in one pot