3939-40-0Relevant academic research and scientific papers
The effect of hydrogen bonding and azomethine group orientation on liquid crystal properties in benzylidene aniline compounds
Kshash, Abdullah Hussein
, p. 739 - 747 (2020/10/02)
This study examines the effects of substituents and hydrogen bonding, orientations of imine linkage on the behavior of benzylidene aniline compounds as liquid crystals (LC). Compounds 4-carboxy benzylidene-4-X-aniline (X = H, F, Cl, Br, CH3, OCH3) 1a-6a were synthesized by the reaction of aniline and its substituted derivatives with 4-formylbenzoic acid. Compounds 4-X-benzylidene-4-carboxy aniline (X = H, F, Cl, Br, CH3, OCH3) 1b-6b were synthesized by the reaction of benzaldehyde and its substituted derivatives with 4-aminobenzoic acid using absolute ethanol as the solvent. Synthesized compounds were characterized by FT IR and 1H NMR spectroscopy, liquid crystal properties were investigated using differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) techniques. Based on the mesomorphic properties, it was proven that the compounds 2b-4b are dimorphic exhibiting a smectic and nematic phase, compounds 5b, 6b are monomorphic exhibiting a nematic phase, while compounds 1a-6a and 1b have not shown any mesophase. For compounds 1a-6a hydrogen bonding and reversing imine linkage (in comparison with compounds 1b-6b) caused the absence of their mesomorphic properties.
Synthesis of novel β-amino ketones containing a p-aminobenzoic acid moiety and evaluation of their antidiabetic activities
Tang, Guangxia,Yan, Jufang,Fan, Li,Xu, Jin,Song, Xiaoli,Jiang, Li,Luo, Lingfei,Yang, Dacheng
, p. 490 - 504 (2013/07/11)
The synthesis of two series of β-amino ketones containing a p-aminobenzoic acid moiety (TM-1 and TM-2) using a modified protocol of the Mannich reaction is reported. The molecular structures of a total of tweenty three new target compounds were characterized by 1H NMR, 13C NMR, ESI-MS and HR-MS. Subsequently, their antidiabetic activities were screened in vitro. The α-glucodase inhibition (α-GI) activity of compound 1e reached a remarkable level of 66.50%. The peroxisome proliferator-activated receptor (PPAR) relative activation activities of six compounds are above 80%, and in particular 2i displays an unprecedentedly high PPAR of 130.91%. The structure-activity relationships of the compounds were established. 2i is also subject to further in-depth investigation.
Synthesis of 3-acetoxyazetidin-2-ones and 3-hydroxyazetidin-2-ones with antifungal and antibacterial activity
Walsh,Meegan,Prendergast,Al Nakib
, p. 989 - 1000 (2007/10/03)
The synthesis of a series of 3-acetoxyazetidin-2-ones 3a-n and 3-hydroxyazetidin-2-ones 6a-j is reported together with the antibacterial and antifungal evaluation of these compounds. An additional series of 3-acetoxyazetidin-2-ones 11a-h which possess a free carboxylic acid group on the N-1 aryl ring were obtained by treatment of suitably substituted Schiff bases 10a-h with acetoxyacetyl chloride. The novel bicyclic structures 7-acetoxy-6-phenyl-5-thia-1-azabicyclo[4.2.0]octan-8-one 13 and 7-hydroxy-6-phenyl-5-thia-1-azabicyclo[4.2.0]octan-8-one 14 were also obtained. Many of the compounds displayed antifungal activity in vitro when evaluated against the pathogenic fungi Cryptococcus neoformans, Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Trichosporon cutaneum, while 3-acetoxyazetidin-2-ones 11a-h containing a free carboxylic acid group on the N-1 aryl ring displayed antibacterial activity against Staphylococcus aureus, Proteus vulgaris, Pseudomonas aeruginosa, Bacillus subtilis, Klebsiella aerogenes and Escherischia coli.
