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Both cerium oxide (CeOx) nanoparticles and mefenamic acid (MFA) are known anti-inflammatory agents with hepatoprotective properties and are therefore prescribed for one of the major diseases in the world, nonalcoholic fatty liver disease (NAFLD). To study the potential cytotoxicity and anti-inflammatory effects as well as drug retention of a potential therapeutic CeOx/MFA supramolecular complex, a well-standardized hepatic (HepG2) spheroid model was used. Results showed that the highest cytotoxicity for the CeOx/MFA supramolecular complex was found at 50 μg/mL, while effective doses of 0.1 and 1 μg/mL yielded a significant decrease of TNF-α and IL-8 secretion. Time-resolved analysis of HepG2 spheroids revealed a spatiotemporal distribution of the supramolecular complex and limited clearance from the internal microtissue over a period of 8 days in cultivation. In summary, our results point at rapid uptake, distribution, and biostability of the supramolecular complex within the HepG2 liver spheroid model as well as a significant anti-inflammatory response at noncytotoxic levels.

Both cerium oxide (CeOx) nanoparticles and mefenamic acid (MFA) are known anti-inflammatory agents with hepatoprotective properties and are therefore prescribed for one of the major diseases in the world, nonalcoholic fatty liver disease (NAFLD). To study the potential cytotoxicity and anti-inflammatory effects as well as drug retention of a potential therapeutic CeOx/MFA supramolecular complex, a well-standardized hepatic (HepG2) spheroid model was used. Results showed that the highest cytotoxicity for the CeOx/MFA supramolecular complex was found at 50 μg/mL, while effective doses of 0.1 and 1 μg/mL yielded a significant decrease of TNF-α and IL-8 secretion. Time-resolved analysis of HepG2 spheroids revealed a spatiotemporal distribution of the supramolecular complex and limited clearance from the internal microtissue over a period of 8 days in cultivation. In summary, our results point at rapid uptake, distribution, and biostability of the supramolecular complex within the HepG2 liver spheroid model as well as a significant anti-inflammatory response at noncytotoxic levels.

In this paper, a water-soluble racemic self-assembled tetrahedral cage [Fe4L6](4-) was successfully resolved into their ΔΔΔΔ and ΛΛΛΛ enantiomers by (R)-/(S)-1,1'-bi-2-naphthol. The enantiomeric excess of the resolved Fe(II) cage was 99%.

National Natural Science Foundation of China [20773098, 20973136]; Innovation Foundation of Xiamen University [XDKJCX20061027]

Eight-coordinate chiral lanthanide complexes [Eu(dbm)3L RR ] (1), [Eu(dbm)3L SS ] (2) and [Tb(dbm)3L RR ] (3) (L RR /L SS = (-)-/(+)-4,5-pineno-2,2′-bipyridine, Hdbm = dibenzoylmethane) were synthesized stereoselectively, which were characterized by UV-vis, CD spectra and X-ray single-crystal diffraction. The mirror-image structure features of complexes 1 and 2 were obtained by combination of the solid-state CD spectra and the crystal structure analysis. After further comparison with the solid-state CD spectra of six-coordinate and seven-coordinate metal complexes containing β-diketone ligands, the CD spectra-absolute configuration correlation rule for the eight-coordinate β-diketonate lanthanide complexes was proposed through the exciton chirality method for the first time. The Δ or Λ absolute configurations of complexes 1–3 with the distorted square antiprism geometry were confirmed by the X-ray single-crystal analysis.

A novel D3T derivative, 5-amino-4-cyano-3H-1,2-dithiole-3-thione (compound 1) has been obtained in one-pot reaction. The crystal is orthorhombic, space group Pbca, with a = 10.3667(4) A, b = 10.8898(4) A, c = 11.4942(5) A, V = 1297.60(9) A3, and Z = 8. In the crystal, molecules are firstly self-assembled into a complex sheet parallel to the (0 0 1) plane containing centrosymmetric R 2 4 (16) and R 4 4 (24) rings, and then the interconnection of molecular sheets through S···S interactions forms a three-dimensional supramolecular assembly. The DFT calculations are performed for isolated molecule using the B3LYP/6-31+G(d,p) methods. The frontier orbital properties of compound 1 have been reported and discussed. Moreover, a detailed assignment of the fundamental vibrational modes is proposed on the basis of the calculated results.

Two chiral dinuclear cyanide/isocyanide-bridged complexes (R)-[Cp(dppe)Fe-CN-Fe(dppp)Cp]PF6 (1[PF6]) and (R)-[Cp(dppe)Fe-NC-Fe(dppp)Cp]PF6 (2[PF6]), and their mono-oxidation products (R)-[Cp(dppe)Fe(II)-CN-Fe(III)(dppp)Cp] [PF6]2 (1[PF6]2) and (R)-[Cp(dppe)Fe(III)-NC-Fe(II)(dppp)Cp][PF6]2 (2[PF6]2) were synthesized and fully characterized. The electronic spectra of both the mixed-valence complexes 1[PF6]2 and 2[PF6]2 exhibit a strong and broad absorption band with two discernable peaks in the NIR region, which are attributed to Fe(II)-Fe(III) IVCT transitions. The attributions are supported by the DFT calculations. Under irradiation with a nanosecond laser at 1064 nm, the measured third-order NLO results of all four cyanide-bridged complexes showed that complexes 1(+) and 2(+) do not exhibit an NLO response, but their one-electron oxidation complexes 1(2+) and 2(2+) exhibit a strong NLO response due to a resonance enhanced effect. In addition, both complexes 1(2+) and 2(2+) display RSA and self-defocusing effects and show good optical limiting behavior in a broadband range.

Chiral tetrakis(β-diketonate) Ln(III) complexes Δ-[NaLa(d-hfc)(4)(CH(3)CN)] (1) and Λ-[NaLa(l-hfc)(4) (CH(3)CN)] (2) (d/l-hfc(-) = 3-heptafluo-robutylryl-(+)/(-)-camphorate) are a pair of enantiomers and crystallize in the same Sohncke space group (P2(1)2(1)2(1)) with dodecahedral (DD) geometry. Typically positive and negative exciton splitting patterns around 320 nm were observed in the solid-state circular dichroism (CD) spectra of complexes 1 and 2, which indicate that their shell configurational chiralities are Δ and Λ, respectively. The apparent bisignate couplets in the solid-state CD spectra of [CsLn(d-hfc)(4)(H(2)O)] [Ln = La (3), Yb (5)] and [CsLn(l-hfc)(4)(H(2)O)] [Ln = La (4), Yb (6)] show that they are a pair of enantiomers and their absolute configurations are denoted Δ and Λ, respectively. The crystallographic data of 5 reveals that its coordination polyhedron is the square antiprism (SAP) geometry and it undergoes a phase transition from triclinic (α phase, P1) to monoclinic (β phase, C2) upon cooling. The difference between the two phases is brought about by the temperature dependent behaviour of the coordination water molecules, but this did not affect the configurational chirality of the Δ-SAP-[Yb(d-hfc)(4)](-) moiety. Furthermore, time-dependent CD, UV-vis and (19)F NMR were applied to study the solution behavior of these complexes. It was found that the chiral-at-metal stability of the three pairs of complexes is different and affected by both the Ln(3+) and M(+) ion size. The results show that the Cs(+) cation can retain the metal center chirality and stablize the structures of [Ln(d/l-hfc)(4)](-) or the dissociated tris(d/l-hfc)Ln(III) species in solution for a longer time than that of the Na(+) cation, and it is important that the Cs(+) ion successfully lock the configurational chirality around the Yb(3+) center of the complex species in solution. This is reasoned by the short Cs(+)···FC, Cs(+)···O-Yb and Cs(+)···Yb(3+) interactions observed in the crystal structure of α-5 and further confirmed by the chiral self-assembly of 5 or 6 from [Yb(H(2)O)(d/l-hfc)(3)] induced by CsI in a CHCl(3) solution.

A photochromism molecule, (E)-4-phenyl-1-(pyridine-2-ylmethylene)semicarbazide (1), was reported. Photochromism of 1 in solution was shown to result from the trans–cis photoisomerization of its CN double bond, by using absorption, 1H NMR (including 2D NOESY) and directly the crystal structure of 1 obtained from solutions before and after UV irradiation. Photochromism of 1 in the solid state was found to take place, too, but via changes in the molecular geometry and packing upon UV irradiation.

The present work examines the relationship between the crystal structures and chiroptical properties of four chiral Yb(III) complexes with camphor-derivative β-diketone ligands by means of solid-state circular dichroism (CD) spectroscopy. For the seven-coordinate complexes, [Yb(H2O)(d-hfc)3] (I) and [Yb(H2O)(l-hfc)3] (II) (d/l-hfc− = 3-heptafluorobutyryl-(+)/(−)-camphorate), the Λ- and Δ-diastereomers coexist in their crystals and no apparent bisignate couplets are observed in their solid-state CD spectra. A theoretical study indicates that the ground-state energy difference between the two diastereomers I and II is only 0.913 kcal mol−1, which explains why they could coexist in a crystal environment with the ratio of 1:1. While, eight-coordinate complexes Δ-[Yb(TPPO)2(d-hfc)3]·CHCl3·3C6H12 (III) and Λ-[Yb(TPPO)2(l-hfc)3]·CHCl3·3C6H12 (IV) (TPPO = triphenylphosphine oxide) are enantiopure in the solid-state, and typically negative and positive exciton splitting patterns around 330 nm are observed in their solid-state CD spectra. The solid-state CD spectra of these four complexes are in accordance with their X-ray single-crystal analyses. Besides, their solution CD spectra show that no particular isomer predominates in solution.

In the title compound, [Tb(C(15)H(11)O(2))(3)(C(17)H(18)N(2))], the 7,7-dimethyl-3-(2-pyrid-yl)-5,6,7,8-tetra-hydro-6,8-methano-iso-quin-oline (L(RR)) ligand coordinates to Tb(III) through the two N atoms of the heterocycle. The metal centre is also chelated by three deprotonated 1,3-diphenyl-propane-1,3-dione (dbm) ligands, forming enanti-omerically pure [Tb(dbm)(3)L(RR)]. The Tb(III) atom is located in a distorted square anti-prism of eight coordinating atoms (six O and two N atoms).