DNA binding affinities, anti-oxidant, antimicrobial and molecular docking activities of Pd (II) complexes of chromone Schiff bases

Palladium(II) complexes containing andrographolide appended N,O heterocyclic chelators: Investigation of anti-oxidant, anti-cancer and apoptotic activities

A series of new Pd(II) complexes were synthesized from the reaction of andrographolide appended hydrazide derivatives with potassium tetrachloropalladate K2[PdCl4]. The formation of the complexes was confirmed through structural assessments conducted using various spectroscopic techniques. From the spectral studies we confirmed that the ligands coordinated to Pd(II) ion via amine nitrogen and enone oxygen. The complexes were assessed for their antioxidant properties, demonstrating significant radical scavenging activity with a series of free radicals such as 1,1-diphenyl-2-picrylhydrazyl (DPPH•), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid diammonium salt (ABTS•+), Super oxide (O2-) and Nitric oxide (NO•) radicals compared with standard antioxidants. Moreover, in vitro antiproliferative investigations conducted on A549 (human lung cancer) and HeLa (human cervical cancer) cell lines revealed significant cytotoxicity of the complexes, with lower IC50 values compared to the standard metallo-drug cisplatin. Morphological alterations observed in HeLa and A549 cells when treated with IC50 concentrations of the complexes, as examined through Acridine Orange-Ethidium Bromide (AO-EB) and 4',6-diamidino-2-phenylindole (DAPI) staining techniques, indicated cell death via apoptosis. Biological studies indicated that AGC-Pd exhibited superior activity among others, further the percentages of the apoptotic and necrotic cells were determined by flow cytometric technique.

Advances in chromone-based copper(ii) Schiff base complexes: synthesis, characterization, and versatile applications in pharmacology and biomimetic catalysis

Chromones are well known as fundamental structural elements found in numerous natural compounds and medicinal substances. The Schiff bases of chromones have a much wider range of pharmacological applications such as antitumor, antioxidant, anti-HIV, antifungal, anti-inflammatory, and antimicrobial properties. A lot of research has been carried out on chromone-based copper(ii) Schiff-base complexes owing to their role in the organometallic domain and promise as potential bioactive cores. This review article is centered on copper(ii) Schiff-base complexes derived from chromones, highlighting their diverse range of pharmacological applications documented in the past decade, as well as the future research opportunities they offer.

NiII and CoII binary and ternary complexes of 3-formylchromone: spectroscopic characterization, antimicrobial activities, docking and modeling studies

Reactions of 3-formylchromone (L) with Ni(ii) and Co(ii) ions having different anions (acetate, perchlorate, nitrate, and chloride) yielded a series of binary and ternary octahedral complexes with the general formula [ML n L' m X y (S) a ]Z y ·bS, where M = Ni or Co, n = 1-3, L' = auxiliary ligand = 8-hydroxyquinoline or 1,10-phenanthroline, m = 1 or 2, X = acetate or chloride, y = 0 or 2, S = H2O or MeOH, a = 0-2, Z = nitrate or perchlorate and b = 0-1.5. Elemental and thermal analyses and infra-red, electronic, mass, magnetic susceptibility and molar conductivity measurements were successfully utilized to characterize the structures of the chromone complexes. The chromone ligand acts as a neutral bidentate ligand through its formyl and γ-pyrone oxygen atoms. The obtained complexes were formed with molar ratios 1 : 2 and 1 : 3 M : L for the binary and 1 : 2 : 1 and 1 : 1 : 1 M : L : L' for the ternary complexes. The kinetic parameters of the thermal degradation steps were estimated and explained using the Coats-Redfern equations. The synthesized complexes showed antimicrobial activity with higher activity toward Candida albicans and Bacillus subtilis. Docking studies showed good agreement with the antimicrobial activity. Molecular modeling of the synthesized complexes was performed using Hyperchem at the PM3 level and the calculated structures correlate with the experimental data.

Silver-catalysed three-component reactions of alkynyl aryl ketones, element selenium, and boronic acids leading to 3-organoselenylchromones

An Ag-catalysed three-component reaction of alkynyl aryl ketones bearing an ortho-methoxy group, element selenium, and arylboronic acid, providing a facile route to selenofunctionalized chromone products has been developed. This protocol features high efficiency and high regioselectivity, and the use of selenium powder as the selenium source. Mechanistic experiments indicated that the combined oxidative effect of (bis(trifluoroacetoxy)iodo)benzene and oxygen in the air pushes the catalytic redox cycle of the Ag catalyst and the phenylselenium trifluoroacetate formed in situ is the key intermediate of the PIFA-mediated 6-endo-electrophilic cyclization and selenofunctionalization reaction of alkynyl aryl ketones.