Investigations on the synthesis and properties of N-phenyl derivatives of 1,4-dioxo(1,4,5-trioxo)-1,2,3,4-tetra(1,2,3,4,5,6-hexa) hydropyrido-[3,4-d]pyridazines and allied compounds

Synthesis, Cyclooxygenases Inhibition Activities and Interactions with BSA of N-substituted 1H-pyrrolo[3,4-c]pyridine-1,3(2H)-diones Derivatives

Inhibition of cyclooxygenase is the way of therapeutic activities for anti-inflammatory pharmaceuticals. Serum albumins are the major soluble protein able to bind and transport a variety of exogenous and endogenous ligands, including hydrophobic pharmaceuticals. In this study, a novel N-substituted 1H-pyrrolo[3-c]pyridine-1,3(2H)-diones derivatives were synthesized and biologically evaluated for their inhibitory activity against cyclooxygenases and interactions with BSA. In vitro, COX-1 and COX-2 inhibition assays were performed. Interaction with BSA was studied by fluorescence spectroscopy and circular dichroism measurement. The molecular docking study was conducted to understand the binding interaction of compounds in the active site of cyclooxygenases and BSA. The result of the COX-1 and COX-2 inhibitory studies revealed that all the compounds potentially inhibited COX-1 and COX-2. The IC₅₀ value was found similar to meloxicam. The intrinsic fluorescence of BSA was quenched by tested compounds due to the formation of A/E-BSA complex. The results of the experiment and molecular docking confirmed the main interaction forces between studied compounds and BSA were hydrogen bonding and van der Waals force.

Design, synthesis and antibacterial activity of new phthalazinedione derivatives

Dibenzobarrelene (1) was utilized as the key intermediate for the synthesis of some new 2-substituted (1,4-dioxo-3,4,4e,5,10,10ahexahydro- 1H-5,10-benzeno-benzo[g]phthalazine: 2, 5a-d, 8a-c and 10. Condensation of 2 with benzaldehyde or anisaldehyde gave the corresponding acrylonitrile derivative 3a, b, respectively. Thiophene derivatives 4a, b were obtained via the Gewald reaction of 2 with cyclohexanone or pentanone, respectively. Treatment of 5d with acetyl chloride or p-toluenesulfonyl chloride afforded the corresponding esters 6, 7, respectively. Cyclization of 8a-c with formalin afforded the corresponding triazine derivatives 9a-c. Ring opening of 10 with sodium hydroxide gave the corresponding triazole derivative 11, which when alkylated with pentyl bromide afforded the pentylsulfanyl derivative 12. Representative compounds of the synthesized products were established and evaluated as antibacterial agents.