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, Pd (8a-j), and Pt (9a-j) dithiolenes belonging to the general class [M(R,R′timdt) 2 ] (R,R′timdt ) monoanion of di-substituted imidazolidine-2,4,5-trithione) have been synthesized by sulfuring the disubstituted imidazolidine-2-thione-4,5-diones (4) with Lawesson's reagent (5) in the presence of the appropriate metal either as powder or as chloride. The obtained compounds have been characterized by UV-vis-NIR, FT-IR, and FT-Raman spectroscopies, CP-MAS 13 C NMR, and cyclic voltammetry, while [Ni(Me,Pr i timdt) 2 ] (7c) was also characterized by X-ray diffraction on a single crystal. Isolation from the reaction mixtures of the complex trans-bis [O-ethyl(4-methoxyphenyl)phosphonodithioato]Ni(II) (10a) and of 4,5,6,7-tetrathiocino[1,2-b:3,4-b′]diimidazolyl-1,10-diphenyl-3,8-diethyl-2,9-dithione (6a) as byproducts supports a radical mechanism for the one-pot reaction leading to the title dithiolenes. All these complexes absorb in the NIR region in the range 991-1030 nm with extinction coefficients of rarely encountered magnitudes (up to 80000 M -1 cm -1 ). They are therefore ideal candidates for applications on Nd:YAG laser technology for which the excitation wavelength is 1064 nm. Hybrid-DFT calculations have been used to gain an insight on the properties of this class of dithiolenes compared with those of the simplest [M(S 2 C 2 H 2 ) 2 ] [M ) Ni (1); M ) Pd (2); M ) Pt (3)] and of the well-known [M(dmit) 2 ] [dmit ) C 3 S 5 2-, 1,3-dithiole-2-thione-4,5-dithiolate; M ) Ni (11); M ) Pd (12); M ) Pt (13)] dithiolenes.

This work was devoted to the development of a new type of lipid-based (cubosome) theranostic nanoparticle able to simultaneously host camptothecin, a potent anticancer drug, and a squarain-based NIR-emitting fluorescent probe. Furthermore, to confer targeting abilities on these nanoparticles, they were dispersed using mixtures of Pluronic F108 and folate-conjugated Pluronic F108 in appropriate ratios. The physicochemical characterization, performed via SAXS, DLS, and cryo-TEM techniques, proved that aqueous dispersions of such cubosomes can be effectively prepared, while the photophysical characterization demonstrated that these nanoparticles may be used for in vivo imaging purposes. The superior ability of these innovative nanoparticles in targeting cancer cells was emphasized by investigating the lipid droplet alterations induced in HeLa cells upon exposure to targeted and nontargeted cubosomes.

The macrocycles L(1)-L(3) incorporating N(2)S(3)-, N(2)S(2)O-, and N(2)S(2)-donor sets, respectively, and containing the 1,10-phenanthroline unit interact in acetonitrile solution with heavy metal ions such as Pb(II), Cd(II), and Hg(II) to give 1:1 ML, 1:2 ML(2), and 2:1 M(2)L complex species, which specifically modulate the photochemical properties of the ligands. The stoichiometry of the complex species formed during spectrofluorometric titrations and their formation constants in MeCN at 25 degrees C were determined from fluorescence vs M(II)/L molar ratio data. The complexes [Pb(L(1))][ClO(4)](2).(1)/(2)H(2)O (1), [Pb(L(2))][ClO(4)](2).MeNO(2) (1a), [Pb(L(3))(2)][ClO(4)](2).2MeCN (1b), and [Cd(L(3))][NO(3)](2) (2b) were also characterized by X-ray diffraction studies. The conformation adopted by L(1)-L(3) in these species reveals the aliphatic portion of the rings folded over the plane containing the heteroaromatic moiety with the ligands trying to encapsulate the metal center within their cavity. In 1, 1a, and 2b the metal ion completes the coordination sphere by interacting with counteranion units and solvent molecules. On the contrary, the 1:2 complex 1b shows Pb(II) sandwiched between two symmetry-related molecules of L(3) reaching an overall [4N + 4S] eight-coordination.

In this work, monoolein-based cubosomes were doped with two fluorescent probes, namely, fluorescein and dansyl, properly modified with a hydrocarbon chain to increase their encapsulation efficiency within the monoolein palisade. The same nanocarriers were also loaded with quercetin, a hydrophobic molecule with potential anticancer activity. Particularly, the cubosomes doped with the modified fluorescein probe were successfully exploited for single living cell imaging. The physicochemical and photophysical characterizations reported here, along with the well-known ability of cubosomes in hosting molecules with pharmaceutical interest, strongly encourage the use of these innovative fluorescent nanocarriers for theranostic purposes.

Interaction of methimazole (MMI, 1-methyl-imidazole-2-thione) with I2 in solvents having different polarity gives two new stable compounds containing a dication disulfide and a monocation disulfide arranged in dimers, respectively. These two species could represent effective intermediates in the reaction of MMI with an active iodine species in the thyroid gland and therefore shed more light on the mechanism of action of MMI as an antithyroid drug.

The coordination chemistry of the new pyridine-based, N2S2-donating 12-membered macrocycle 2,8-dithia-5-aza-2,6-pyridinophane (L1) towards Cu(II), Zn(II), Cd(II), Hg(II), and Pb(II) has been investigated both in aqueous solution and in the solid state. The protonation constants for L1 and stability constants with the aforementioned metal ions have been determined potentiometrically and compared with those of ligand L2, which contains a N-aminopropyl side arm. The measured values show that Hg(II) in water has the highest affinity for both ligands followed by Cu(II), Cd(II), Pb(II), and Zn(II). For each metal ion considered, 1:1 complexes with L1 have also been isolated in the solid state, those of Cu(II) and Zn(II) having also been characterised by X-ray crystallography. In both complexes L1 adopts a folded conformation and the coordination environments around the two metal centres are very similar: four positions of a distorted octahedral coordination sphere are occupied by the donor atoms of the macrocyclic ligand, and the two mutually cis-positions unoccupied by L1 accommodate monodentate NO3- ligands. The macrocycle L1 has then been functionalised with different fluorogenic subunits. In particular, the N-dansylamidopropyl (L3), N-(9-anthracenyl)methyl (L4), and N-(8-hydroxy-2-quinolinyl)methyl (L5) pendant arm derivatives of L1 have been synthesised and their optical response to the above mentioned metal ions investigated in MeCN/H2O (4:1 v/v) solutions.