TITLE:
Synthesis, Molecular Structure, Anti-Plasmodial, Antimicrobial and Anti-Oxidant Screening of (E)-1-(Phthalazin-1-yl)-1-[(Pyridin-2-yl)Ethylidene]Hydralazine and 1-[2-(1-(pyridine-3- yl)ethylidene)hydrazinyl]phthalazine
AUTHORS:
Angelbert F. Awantu, Godfred A. Ayimele, Jean Jules K. Bankeu, Edouard A. Nantia, Patrick V. T. Fokou, Fabrice F. Boyom, Emmanuel N. Nfor, Bruno N. Lenta, Silvère A. Ngouela
KEYWORDS:
Schiff Base, Hydralazine Hydrochloride, Anti-Plasmodial Activity, Antimicrobial Activity, Anti-Oxidant Activity
JOURNAL NAME:
International Journal of Organic Chemistry,
Vol.11 No.3,
August
11,
2021
ABSTRACT: Two new hydralazine hydrochloride-derived Schiff bases:(E)-1-(Phthalazin-1-yl)-1-[(Pyridin-2-yl)Ethylidene]Hydralazine (PPEH), and 1-[2-(1-(pyridine-3-yl)ethylidene)hydrazinyl]phthalazine (PEHP), were synthesized and partially characterized by spectroscopic and crystallographic methods including IR and X-ray. The single-crystal X-ray diffraction (SCXRD) analysis of PEHP indicatesthat the hydralazine moiety of both ligands possessesthe exocyclic C=N bond. Both, PPEH and PEHP were tested as antimicrobials and antiparasites. Just PEHP could be considered as slightly antiplasmodial and antibacterial agent. In effect, PPEH showed low antimicrobial activity against one bacterial strain with Minimum Inhibitory Concentration (MIC) value of 250 μg/ml while PEHP showed very interesting activity against 18 out of 19 bacterial strains with MIC of 31.25 -250 μg/ml compared to the standard drug, amoxicillin. PPEH and PEHP showed higher reducing activity on ferric ions compared to Vitamin C. On the other hand, both hidrazaline synthetized derivatives showedas better reducing agents than Vitamin C on ferric ions, while again, only the PEHP showedslightly high inhibition of lipid peroxidation using Vitamin C as standard. Regarding their catalase activity, both compounds showedconcentration dependent effect, but Vitamin C continued showing a higher stimulatory effect on the enzyme activity. Additionally, while PPEH showed less than 80% inhibition in the preliminary antiplasmodial assay and so was not considered for the dose-response studies, PEHPdisplayed an inhibition percentage of 83.60% and 50% Inhibitory Concentration (IC50) value of 44.13 μg/mL compared to the standard drug, artemisinin and was classified as slightly active.