A novel hybrid iron fluoride based on 8-hydroxyquinoline: Crystal structure, thermal decomposition, spectroscopic characterization, and magnetic properties

Adamantane-type clusters: compounds with a ubiquitous architecture but a wide variety of compositions and unexpected materials properties

The research into adamantane-type compounds has gained momentum in recent years, yielding remarkable new applications for this class of materials. In particular, organic adamantane derivatives (AdR4) or inorganic adamantane-type compounds of the general formula [(RT)4E6] (R: organic substituent; T: group 14 atom C, Si, Ge, Sn; E: chalcogenide atom S, Se, Te, or CH2) were shown to exhibit strong nonlinear optical (NLO) properties, either second-harmonic generation (SHG) or an unprecedented type of highly-directed white-light generation (WLG) - depending on their respective crystalline or amorphous nature. The (missing) crystallinity, as well as the maximum wavelengths of the optical transitions, are controlled by the clusters' elemental composition and by the nature of the organic groups R. Very recently, it has been additionally shown that cluster cores with increased inhomogeneity, like the one in compounds [RSi{CH2Sn(E)R'}3], not only affect the chemical properties, such as increased robustness and reversible melting behaviour, but that such 'cluster glasses' form a conceptually new basis for their use in light conversion devices. These findings are likely only the tip of the iceberg, as beside elemental combinations including group 14 and group 16 elements, many more adamantane-type clusters (on the one hand) and related architectures representing extensions of adamantane-type clusters (on the other hand) are known, but have not yet been addressed in terms of their opto-electronic properties. In this review, we therefore present a survey of all known classes of adanmantane-type compounds and their respective synthetic access as well as their optical properties, if reported.

Low-dimensional compounds containing bioactive ligands. Part XVII: Synthesis, structural, spectral and biological properties of hybrid organic-inorganic complexes based on [PdCl4]2- with derivatives of 8-hydroxyquinolinium

In this study, four hybrid organic-inorganic compounds (8-H₂Q)₂[PdCl₄] (1), (H₂ClQ)₂[PdCl₄] (2), (H₂NQ)₂[PdCl₄] (3) and (H₂MeQ)₂[PdCl₄]·2H₂O (4) (where 8-H₂Q = 8-hydroxyquinolinium, H₂ClQ = 5-chloro-8-hydroxyquinolinium, H₂NQ = 5-nitro-8-hydroxyquinolinium and H₂MeQ = 2-methyl-8-hydroxyquinolinium) were synthesized through organic cation modulation. Single-crystal X-ray structure analysis of compounds 1 and 3 indicates that their structures are planar and consist of [PdCl₄]^2- anions and 8-H₂Q or H₂NQ cations, respectively. Both ionic components are held together through ionic interactions and hydrogen bonds forming infinite chains linked through π-π interactions to form 2D structures. Furthermore, NMR spectroscopy, UV-Vis spectroscopy, elemental analysis, and FT-IR spectroscopy were used to explore the synthesized compounds. The DNA interaction, antimicrobial activity, antiproliferative activity, and radical scavenging effect of the compounds were evaluated. The hybrid compounds and their free ligands can interact with the calf thymus DNA via an intercalation mode involving the insertion of the aromatic chromophore between the base pairs of DNA; compound 1 has the highest binding affinity. Moreover, they have high antimicrobial efficacy against the tested 14 strains of microorganisms with minimum inhibitory concentration values ranging from <1.95 to 250 μg/mL. The antiproliferative activity of the compounds was investigated against three different cancer cell lines, and their selectivity was verified on mesenchymal stem cells. Compounds 1 and 2 displayed selective and high cytotoxicity against human lung and breast cancer cells and showed moderate cytotoxicity against colon cancer cells. Accordingly, they might be auspicious candidates for future pharmacological investigations in lung and breast cancer research.