Synthesis and evaluation of antiinflammatory, analgesic and ulcerogenic potential of NSAIDs bearing 1,3,4-oxadiazole scaffold

The Chemistry and Bioactivity of Mefenamic Acid Derivatives: A Review of Recent Advances

Mefenamic acid (MA) represents an efficient nonsteroidal anti-inflammatory drug (NSAID) for treatment in many circumstances of painful conditions and inflammation, but its poor water solubility and gastrointestinal side effects often obstruct its clinical application. Consequently, researchers have been conducting studies on the synthesis of prodrugs and heterocyclic compounds as MA derivatives for the improvement of their pharmacological profile. This review discusses an overview of recent developments in the synthesis and biological applications of MA derivatives. It covers several strategies used to modify the chemical structure of MA to pursue pharmacokinetic improvement, solubility, and targeting features, among which are heterocyclic moieties and prodrug design. Following the many synthetically produced derivatives of MA, mainly proposed between classic organic synthesis and more recent methodologies, such as microwave-assisted synthesis and green chemistry protocols, this review will consider how different structural variations are able to influence the assumed pharmacological actions: analgesic, anti-inflammatory, and anticancer. The findings demonstrate significant progress toward the development of safer and more effective NSAID therapies; thus, they support, in a broad and unprecedented way, the potential of MA derivatives and prodrugs in transforming the state of pain management and inflammation treatment.

Two mefenamic acid derivatives: structural study using powder X-ray diffraction, Hirshfeld surface and molecular electrostatic potential calculations

Two mefenamic acid (1) derivatives, prop-2-ynyl 2-(2,3-dimethylphynylamino)benzoate (2) and N′-(dihydro-2H-pyran-4(3H)-ylidene)-2-((2,3-dimethylphenyl)amino)benzohydrazide (3), have been synthesized and their crystal structures have been determined from laboratory powder X-ray diffraction data. The DFT optimized molecular geometry in 2 and 3 agrees closely to that obtained from the crystallographic study. The nature of intermolecular interactions in 2 and 3 has been analyzed through Hirshfeld surfaces and two-dimensional fingerprint plots, and compared with that in the mefenamic acid polymorphs. Intermolecular N–H···N, C–H···O/N and C–H···π(arene) interactions in 2 and 3 assemble molecules into two and three-dimensional supramolecular frameworks, respectively. Hydrogen-bond based interactions in 2 and 3 have been complimented by calculating molecular electrostatic potential surfaces. Hirshfeld surface analyses of 2, 3, three mefenamic acid polymorphs and a few related mefenamic acid derivatives retrieved from the Cambridge Structural Database (CSD) indicate that about 80% of the Hirshfeld surface areas in these compounds are due to H···H and C···H/H···C contacts.

Bis-aryloxadiazoles as effective activators of the aryl hydrocarbon receptor

Bis-aryloxadiazoles are common scaffolds in medicinal chemistry due to their wide range of biological activities. Previously, we identified a 1,2,4-bis-aryloxadiazole that blocks mammary branching morphogenesis through activation of the aryl hydrocarbon receptor (AHR). In addition to defects in mammary differentiation, AHR stimulation induces toxicity in many other tissues. We performed a structure activity relationship (SAR) study of 1,2,4-bis-aryloxadiazole to determine which moieties of the molecule are critical for AHR activation. We validated our results with a functional biological assay, using desmosome formation during mammary morphogenesis to indicate AHR activity. These findings will aid the design of oxadiazole derivative therapeutics with reduced off-target toxicity profiles.