Synthesis, characterization and thermal oxidative stability of rigid epoxy polymers cured from aromatic mono- and di-amines

Synthesis and bioelectrochemical behavior of aromatic amines

Four aromatic amines 1-amino-4-phenoxybenzene (A₁), 4-(4-aminophenyloxy) biphenyl (A₂), 1-(4-aminophenoxy) naphthalene (A₃) and 2-(4-aminophenoxy) naphthalene (A₄) were synthesized and characterized by elemental, spectroscopic (FTIR, NMR), mass spectrometric and single crystal X-ray diffraction methods. The compounds crystallized in monoclinic crystal system with space group P2₁. Intermolecular hydrogen bonds were observed between the amine group and amine/ether acceptors of neighboring molecules. Electrochemical investigations were done using cyclic voltammetry (CV), square wave voltammetry (SWV) and differential pulse voltammetry (DPV). CV studies showed that oxidation of aromatic amines takes place at about 0.9 V (vs. Ag/AgCl) and the electron transfer (ET) process has irreversible nature. After first scan reactive intermediate were generated electrochemically and some other cathodic and anodic peaks also appeared in the succeeding scans. DPV study revealed that ET process is accompanied by one electron. DNA binding study of aromatic amines was performed by CV and UV-visible spectroscopy. These investigations revealed groove binding mode of interaction of aromatic amines with DNA.

Synthesis, Characterization, and Pharmacological Evaluation of Selected Aromatic Amines

Aromatic amines 1-amino-4-phenoxybenzene (A-1A), 2-(4-aminophenoxy) naphthalene (A-2A), and 1-(4-aminophenoxy) naphthalene (A-3A) were synthesized by the reduction of corresponding nitroaromatics with hydrazine monohydrate and Pd/C 5% (w/w). The newly synthesized compounds were characterized by FTIR,1H NMR,13C NMR, UV-visible spectrophotometer, and mass spectrometry and their biological activities were investigated along with structurally similar 4-(4-aminophenyloxy) biphenyl (A-A). Results of brine shrimp cytotoxicity assay showed that almost all of the compounds had LD50values <1 μg/mL. The compounds also showed significant antitumor activity with IC50values ranging from 67.45 to 12.2 µgmL−1. The cytotoxicity and antitumor studies correlate the results which suggests the anticancerous nature of compounds. During the interaction study of these compounds with DNA, all of the compounds showed hyperchromic effect indicating strong interaction through binding with the grooves of DNA. Moreover, A-3A also showed decrease inλmaxconfirming higher propensity for DNA groove binding. In DPPH free radical scavenging assay, all the compounds showed potential antioxidant capability. The compounds were highly active in protecting DNA against hydroxyl free radicals. DNA interaction and antioxidant results back up each other indicating that these compounds have potential to be used as cancer chemopreventive agents. Additionally, one compound (A-1A) showed significant antibacterial and antifungal activity as well.