Photochemical Reaction of Nalidixic Acid in Methanol
The photochemical reactions of methanolic nalidixic acid (NAL) solution in the absence and in the presence of air have been investigated using 300 nm UV light. From the reactions, 1-ethyl-7-methyl-4-oxo-4-hydro-1,8naphthyridine (EMDN), formic acid, and formaldehyde are produced. In the presence of air, hydrogen peroxide is also detected along with the products listed above. The presence of oxygen during the irradiation of methanolic NAL solution effects on the product yield. The initial quantum yields of the products and of the NAL decomposition are determined. Possible reaction pathways for the photochemical reaction are suggested on the basis of the products analysis.
Photochemical behavior of levofloxacin
The effect of intermolecular proton transfer on the spectral properties of levofloxacin in the ground and excited electronic states was studied. The preferred direction of possible protolytic reactions induced by UV irradiation in this compound was studied. It was found that the proton transfer processes have a considerable effect on the capability of the compound to emit light and occur on the nanosecond time scale.
Modulating dopamine receptors subtype selectivity by thiophene and benzothiophene based derivatives
In this work we tried to develop new dopaminergic ligands with novel affinity and selectivity profile towards the five different dopamine receptor subtypes; namely D1, D2, D3, D4, and D5 receptors to come up with new medical agents but with fewer side effects relative to those present in the medicinal market such as Haloperidol that is considered to be among the very famous typical antipsychotic agents characterized with Extrapyramidal symptoms adverse effects and Clozapine that represents the atypical antipsychotic agents that suffers agranulocytosis adverse effects. Among the fifty five synthesized ligands, compounds 3, 44a, and 45a were shown to have unique subtype receptor selectivity, thus could be promising atypical antipsychotic agents. Compound 3 was the first azecine derivative to show antagonistic action on both D2 and D5 receptor subtypes, (Ki (D2): 1.5 nM; Ki (D5): 1.9 nM). Compound 44a showed to be more than 200 times more selective to D2 receptors rather than D4 (Ki (D2): 138 nM; Ki (D4):0.62 nM). Compound 45a has shown to be more than 100 times more selective to D3 rather than D2 receptor subtypes and more than 900 times more selective to D4 rather than D2 receptor subtypes (Ki (D2): 28.5 nM; Ki (D3): 0.26 nM; Ki (D4): 0.03 nM).