Novel copper(II) complexes of two tridentate ONN type ligands: Synthesis, characterization, electrical conductivity and luminescence properties

Differential Immunomodulatory Activities of Schiff Base Complexes Depending on their Metal Conjugation

Immunomodulatory compounds have become crucial with advances in immunotherapy. Using our own immune system cells, we can direct the immune cell function and develop desired response against a certain threat. Immunotherapy applications have been suggested against tumors, autoimmune disorders, and infectious diseases. Vaccination can be considered as one of the best known example of immunotherapy. Infectious agent's signature molecular structures are introduced to the immune cells together with the adjuvants that further activate the immune cells to mount a proper immune response and memory. Immunotherapy and vaccine formulations are in constant need of a library of immunomodulatory reagents that can be applied depending on the target. In order to expand the number of immunomodulatory reagents that can find medicinal applications, our group has been testing unique chemical structures on the immune system cells, especially macrophages. Schiff base complexes are known for their anti-inflammatory and antimicrobial activities. In this study, we used previously characterized Schiff base complexes with different metal conjugations. These molecules had differential immunostimulatory and immunomodulatory potentials on macrophages in vitro depending on the type of the conjugated metal. After light exposure, these complexes changed their characteristics and became powerful anti-inflammatory complexes. Due to their possible antimicrobial potentials, we also tested their activities against gram negative and gram positive bacteria. All of the complexes exerted antimicrobial activities which were not light responsive. Here, we present Schiff base complexes with differential immunostimulatory and immunomodulatory activities that can also efficiently eliminate gram positive and gram negative bacteria. Upon photo activation, they block the production of inflammatory TNFα cytokine. Therefore, together with the light, they can be used to treat bacterial infections associated with damaging inflammation. Graphical Abstract.

Novel Copper Bearing Schiff Bases with Photodynamic Anti-Inflammatory and Anti-Microbial Activities

Schiff bases and their copper complexes have been previously studied for their anti-inflammatory, anti-tumor as well as anti-microbial activities. Schiff bases can be derivatized to gain photoluminiscence capacity. This property of the schiff bases enables the transfer of the electrons upon absorption of the light at a specific wavelength. In this study, we exploited this attribute of novel copper bearing schiff bases and tested their photodynamic biological activities. These compounds exerted photodynamic anti-inflammatory activities on the in vitro activated mammalian macrophages. Compared with salicylic acid control groups, these novel schiff bases had stronger activity which became more prominent with photo-induction. Moreover, they also had anti-microbial activity on gram negative bacteria E.coli and gram positive bacteria S.aureus.This anti-microbial activity was stronger than that of Neomycin on both bacterial strains. Our results suggest their potential use as anti-inflammatory and anti-microbial agents both in the dark as well as after photo-induction.

Synthesis of Pyrazolone Derivatives and Their Nanometer Ag(I) Complexes and Physicochemical, DNA Binding, Antitumor, and Theoretical Implementations

Four pyrazolone derivatives and their corresponding silver complexes were synthesized and characterized. Based on elemental analysis, 1 : 2 (M : L) molar ratio was suggested for all inspected complexes. ¹H, ¹³C NMR, mass, UV-Vis, TGA, and IR were the spectral tools used for describing the formulae. Moreover, XRD patterns and SEM pictures were used to evaluate the particle sizes which appeared strongly in nanometer range. CT-DNA study is the major consideration in this study, to test the interacting ability of all synthesized cationic complexes towards cell DNA. Each binding constant was computed and correlated with the Hammett sigma constant. Antitumor activity was examined upon three carcinoma cell lines (MCF-7, HepG2, and HCT116). The high efficiency was recorded towards MCF-7 (breast carcinoma) cell line. Kinetic studies yield essential parameters to assert on the rule of metal atom on thermal feature of organic compounds. Molecular modeling was implemented to optimize the structures of compounds. Also, molecular docking was achieved to obtain a clear view about proposed drug behavior within the affected cells. This was achieved through comparing the calculated internal energy values of all docking complexes. All the tested compounds displayed a significant interaction with breast cancer protein (strong matching with practical result) followed by DNA polymerase protein.