Unconventional dual inclusion of metal-organic guests in self-assembled anion-water hosts and infinite ADS-water assemblies in Ni(II) and Zn(II) multi-component compounds: Antiproliferative evaluation and theoretical studies

Two new metal-organic multi-component compounds of Ni(II) and Zn(II) involving bipyridine and anthraquinone-1,5-disulphonate viz. [Ni(bipy)(2)(Ac)(H2O)](0.5ADS)center dot 4H(2)O (1) and [Zn-2(bipy)(2)(H2O)(8)](2ADS)center dot 4H(2)O (2) (bipy = 2,2'-bipyridine and ADS = anthraquinone-1,5-disulphonate) have been synthesized and characterized by using elemental analysis, single crystal XRD, electronic and vibrational spectroscopy and TGA. The lattice water and ADS moieties are interconnected via hydrogen bonding interactions to form unusual infinite ADS-water chains, stabilizing the layered assembly of the compounds. The lattice ADS and bipy moieties of the metal complex are involved in O-H center dot center dot center dot O, C-H center dot center dot center dot O, pi-stacking and anion-pi interactions, providing further rigidity to the crystal structure. The fascinating aspect of the crystal structure of 2 is the inclusion of dual metal-organic cationic guests inside the self-assembled ADS-water hosts. The non-covalent interactions e.g., hydrogen bonding, pi-stacking and anion-pi interactions in compound 1 and H-bonding assemblies in compound 2 and their energetic and structure guiding features are further studied using various computational tools, viz. DFT, QTAIM and NCI plot analyses. The anticancer activity of both the compounds was investigated through trypan blue cell cytotoxicity assay in Dalton's Lymphoma (DL) malignant cancer cells with reference to the drug mitomycin and supported by molecular docking studies. Cytotoxicity assay indicates higher cytotoxic effect of compound 1 than compound 2. ADME analysis was further performed to assess the physicochemical properties, lipophilicity, pharmacokinetics properties, drug-likeness properties and bioavailability of the compounds. These results exhibit that both compounds followed the Lipinski rule of five and exhibited a bioavailability score of 0.55, making them a potential drug candidate.