Synthesis, stereochemistry, and antimicrobial activity of 2,6-diaryl-3-(arylthio)piperidin-4-ones.
A series of novel 2,6-diaryl-3-(arylthio)piperidin-4-ones have been synthesized by reaction of arylthioacetones, substituted aromatic aldehydes, and methylamine/ammonium acetate and their structures elucidated by (1)H, (13)C, and 2D NMR (H, H-COSY, C, H-COSY, HMBC, and NOESY) spectroscopy. The NMR data reveal that all these piperidones exist in chair conformation with the 2,6-diaryl groups equatorially oriented, while the arylthio group prefers to be in either an equatorial or axial orientation depending on whether the substituent in the 2,6-diaryl rings is present in 4- or 2-position, respectively. In the case of NH-2,6-diaryl-3-(arylthio)piperidin-4-ones with o-substituted 2,6-diaryl groups, the arylthio group prefers the axial orientation presumably in a bid to minimize the steric and/or electronic repulsion. The arylthiopiperidin-4-ones exhibit significant antibacterial activity against Staphylococcus aureus, Vibrio cholerae, Salmonella typhi, and Escherichia coli and antifungal activity against Candida albicans and Aspergillus niger.
Srinivasan
Murugesan
M
Department of Organic Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai 625 021, India.
Perumal
Subbu
S
Selvaraj
Sangavanaicker
S
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000494:pharmacology; D000935:Antifungal Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D004353:Drug Evaluation, Preclinical; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D008968:Molecular Conformation; D015394:Molecular Structure; D010881:Piperidones / Q000138:chemical synthesis* / Q000494:pharmacology; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D010881:Piperidones