The compounds studied in this work are sol-gel-derived organic-inorganic hybrid materials in which the two components are covalently linked via Si-C bonds. The organic part is a chromophore group derived from dipicolinic acid that is functionalized with trialkoxysilyl groups; the as-obtained silylated monomers are afterward submitted to complexation with rare-earth ions (Eu 3+ , Gd 3+ ) and are used as the siloxane network precursors. The preparation of hybrid materials including covalent grafting and the sol-gel process is described, as well as their luminescence properties. Modifications of the ligand structure (mono-or disubstituted amides) lead to different coordinating properties and to variable absorption edges. As a result, the absorption efficiency or the ability of the chelates to transfer the absorbed energy to Ln 3+ and consequently the quantum yield of the emission are changed. The major effect of silica is a broadening of the emission peaks, whereas spectral repartitions and lifetimes are mainly unchanged as compared with the corresponding organic molecules.

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The development of CDK and GSK3 inhibitors has been regarded as a potential therapeutic approach, and a substantial number of diverse structures have been reported to inhibit CDKs and GSK-3β in recent years. Only a few molecules have gone through or are currently undergoing clinical trials as CDK and GSK inhibitors. In this paper, we prepared valmerins, a new family containing the tetrahydropyrido[1,2-a]isoindone core. The fused heterocycle was prepared with a straightforward synthesis that was functionalized by a (het)arylurea. Twelve valmerins inhibited the CDK5 and GSK3 with an IC(50) < 100 nM. A semiquantitative kinase scoring was realized, and a cellular screening was done. At the end of our study, we investigated the in vivo potency of one valmerin. Mice exhibited good tolerance to our lead, which proved its efficacy and clearly blocked tumor growth. Valmerins appear also as good candidates for further development as anticancer agents.