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Lingzhifuran A (1) and lingzhilactones D–F (2–4), four new phenolic meroterpenoids were isolated from the fruiting bodies of Ganoderma lucidum. Their structures were identified by spectroscopic data. Chiral HPLC analysis indicates the racemic nature of 2–4. Chiral separation followed by X-ray diffraction analysis discloses the absolute configuration of (−)-2. Compounds 1 and 2 could selectively inhibit TGF-β1-induced Smad3 phosphorylation in rat renal tubular epithelial cells, representing novel scaffolds of selective Smad3 activation inhibitors. Total synthesis accompanied by in vivo rodent experiments reveals antifibrotic activities of 1 against kidney fibrosis. Finally, a plausible biosynthetic pathway for 1 was proposed.

Transition metal (TM) cations and clusters have been widely used to functionalize polyoxometalates (POMs) of tungsten, molybdenum and vanadium due to their acidic nature, which made them compatible with addendum TM cations. Together with the good understanding of their solution behavior, a number of TM-based POMs have been achieved, which exhibited potential applications in many fields. Comparably, fewer polyoxoniobates (PONs) were obtained due to the poor understanding of their solution behavior, and they could only exist in strong alkaline aqueous solutions, where most of the TM cations precipitate because of the formation of hydroxide or oxide. Recently, TM cations were introduced into PONs by protection of chelate organic ligands or via selection of alkaline-soluble TM cations. Further, lacunary POMs, composed of early TM cations, were used as polydentate ligands to isolate PONs, and they make the PON clusters stably exist in acidic solutions. The acidic nature of tungstoniobate (W–Nb) clusters allowed acid-soluble TM cations to directly functionalize the Nb–W clusters. This highlight focuses on discussing the roles of TM centers in constructing PON-based materials, including TM-cluster-containing PONs, TM–organic group-decorating PONs and niobate clusters isolated by lacunary POMs. This systematic compilation of TM-PON studies will reveal a promising direction for further functionalization of PONs, and it will disclose a richer and more diverse set of structures in PON chemistry.

The new compound Na18 [Nb48V8(OH)30O130] ·33H2O is synthesized by reaction of K7HNb6O19, VCl3, and NaOH (H2O, 70—75 °C, 5 h, 42% yield).

The cerium(III)-containing polyoxotungstates (III)—(VII) are characterized by single crystal XRD, IR spectroscopy, XPS, ESI-MS, and electrochemical measurements.

Compounds (IV) and (VII) crystallize in the triclinic space group P with Z = 1 (single crystal XRD).

The isotypic compounds (III) crystallize in the monoclinic space group P21/c with Z = 2 (single crystal XRD) and exhibit three-dimensional frameworks with triangular helical channels, which accomodate linear polyiodide chains.

The new compounds (III), (IV), and (V) with molecular triangle, molecular square, and cuboctahedral molecular cage geometries, respectively, are characterized by single crystal XRD and electrospray ionization mass spectrometry.

The new compound {[Cu6(phen)6(H2O)3] [Nb10V4O40(OH)2]}2 ·13H2O is obtained from an aqueous mixture of K7HNb6O19, Cu(OAc)2, NaVO3, phen, and NaOH (pH 11.2, 58 °C, 8 h, 57% yield).

A series of polyoxotungstates based on monovacant Keggin-type anions have been synthesized via a step-by-step assembly process. Reaction of trivacant Keggin-type polyoxotungstate precursors with cupric sulfate at pH ≈ 5 in the presence of 1,2-ethylenediamine (abbreviated as en) led to the isolation of a inorganic–organic hybrid compound, [Cu(en)2][Cu(en)2H2O]2[SiW11CuO39]·5H2O (1). Compound 1 exhibits a 1D chain structure constructed from mono-copper-substituted Keggin silicotungstate grafted by {Cu(en)2} groups. When lanthanide ions were introduced into the present system, H14[Cu(en)2]4[Ce(PW11O39)2]2·2en·21H2O (2), H14[Cu(en)2]4[Pr(PW11O39)2]2·11H2O (3) and H8[Cu(en)2H2O]4[Cu(en)2]{[Cu(en)2][Pr(PW11O39)2]}2·2en·12H2O (4) have been successfully synthesized, which all show 1D chain structures constructed from {Ln(PW11O39)2} and {Cu(en)2} moieties. Magnetic study of 1 reveals weak ferromagnetic interactions exist in it. The cyclic voltammetry behaviors of compounds 2–4 have also been investigated.

H7{ [Na12(PO4)(H2O)12]@ [Mo6O12(OH)3(HPO4)3 (PO4)] 4(Zn6O2)}·38H2O is hydrothermally synthesized from an aqueous solution of H3PO3, Na2MoO4, and ZnCl2 (autoclave, pH 4—5, 170 °C, 5 d; 62% yield).

A new chiral open-framework cobalt phosphite [C6N2H14][Co(HPO3)2] (1) with helical channels has been synthesized under solvothermal conditions in the presence of achiral organic amine. The circular dichroism (CD) spectrum indicates that the bulk crystals have optical activity. Magnetic measurements reveal that 1 is a weak ferromagnet.

The reactions between trivacant Keggin polyanions and transition metal ions in the presence of organoamine resulted in the isolation of two new polyoxotungstates, that is, [Hen]2[Cu(en)2(H2O)]2{[Cu(en)2]2[X2W23CuO79]}·4H2O (X = Ge, 1; X = Si, 2; and en = 1,2-ethylenediamine). Single-crystal X-ray diffraction analyses reveal that the polyanions in 1 and 2 are constructed by saturated Keggin anions condensed through sharing common oxygen atoms into Keggin dimers, which are further fused by copper(II) bridging fragments into one-dimensional (1D) ladder-like chains and then extended to a 3D supramolecular framework through hydrogen bond interactions. The IR spectrum and X-ray powder diffraction have been studied in detail for compounds 1 and 2. The UV spectrum, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), the cyclic voltammetry and electrocatalytic activity toward the reduction of nitrite have also been studied for compound 1.

Four enantiomerically pure 3D chiral POM-based compounds, [Ni(2)(bbi)(2)(H(2)O)(4)V(4)O(12)]2 H(2)O (1 a and 1 b) and [Co(bbi)(H(2)O)V(2)O(6)] (2 a and 2 b) (bbi=1,1'-(1,4-butanediyl)bisimidazole) based on the achiral ligand, different vanadate chains, and different metal centers have been synthesized by hydrothermal methods. Single-crystal X-ray diffraction analyses revealed that 1 a and 1 b, and 2 a and 2 b, respectively, are enantiomers. In 1 a and 1 b two kinds of vanadate chains with different screw axes link Ni cations to generate 3D chiral inorganic skeletons, which are connected by the achiral bbi ligands to form complicated 3D 3,4-connected chiral self-penetrating frameworks with (7(2)8)(7(2)8(2)9(2))(7(3)8(2)10) topology. They represent the first examples of chiral self-penetrating frameworks known for polyoxometalate (POM) systems. Contrary to 1 a and 1 b, in 2 a and 2 b the vanadate chains link Co(II) cations to generate 3D chiral inorganic skeletons, which are assembled from two kinds of heterometallic helical units of opposite chirality along the c axes. The chiral inorganic skeletons are connected by bbi to form 3D 3,4-connected chiral POM-based frameworks with (6(2)8)(2)(6(2)8(2)10(2)) topology. It is believed that the asymmetrical coordination modes of the metal cations in 1 a-2 b generate the initial chiral centers, and that the formation of the various helical units and the hydrogen bond interactions are responsible for preservation of the chirality and spontaneous resolution when the chirality is extended into the homochiral 3D-networks. This is the first known report of chiral POM-based compounds consisting of 3D chiral inorganic skeletons being obtained by spontaneous resolution upon crystallization in the absence of any chiral source, which may provide a rational strategy for synthesis of chiral POM-based compounds by using achiral ligands and POM helical units.

new compounds (H3O)3[{K(H2O)}2{Na2(H2O)8}2(Na0.5H2O)2(H2W12O42)] ·6H2 O( 1 )a nd (H 3O)2[{K(H2O)4}2{Na3(H2O)9}2(H2W12O42)]·2H2 O( 2), which have been isolated from a sodium acetate buffer solution containing decatungstate Na4[W10O32 ]a t different reaction temperatures. Compounds 1 and 2 exhibit three-dimensional (3-D) frameworks with the POM anoins bridging sodium and potassium countercations.

Three new extended frameworks based on the paradodecatungstate cluster and transition metals or alkaline-earth metal have been synthesized and characterized by elemental analysis, IR spectroscopy, thermal gravimetric analysis (TGA), X-ray powder diffraction (XRPD) and single crystal X-ray diffraction. The 2D layered structure of the compound [Na8(H2O)28][Mn(H2O)2(H2W12O42)]·4H2O (1) is formed by the interconnection of 1D [Mn(H2O)2(H2W12O42)]n8− and [Na8(H2O)28]n8+ chains. In the compound [Zn5(H2O)20(H2W12O42)]·16H2O (2), two neighboring paratungstate ions [H2W12O42)]10− are linked by [Zn4(H2O)14]8+ units, leading to the formation of a 2D layer containing rhombic channels. The anion [Sr2(H2O)6(H2W12O42)]6− of the compound K[Na5(H2O)6][Sr2(H2O)6(H2W12O42)]·18H2O (3) shows a layer-like structure in which paratungstate-B units act as six-dentate ligands coordinating to six Sr2+ ions through the terminal oxygen atoms. Interestingly, the strong involvement of the potassium and sodium counteractions leads the neighboring layers to tie together generating a 3D network containing two types of channels. Furthermore, compounds 1–3 give intense blue luminescent emissions in solid state and the magnetic susceptibility of compound 1 has also been studied.

Two new enantiomerically chiral 3D architectures, l-(Zn(H2O)3)3[MnMo9O32]·4H2O and d-(Zn(H2O)3)3[MnMo9O32]·4H2O, have been produced from a new way. The compounds were composed of the discrete chiral [MnMo9O32]6- polyoxoanions linked by zinc(II) atoms to a 3D framework with a 2-fold interpenetrating net, which is the first examples of POM-based chiral 3D frameworks consisting of only inorganic components.

Two novel high-nuclear Ni-substituted polyoxometalates Na9K[Ni7(OH)4(H2O)(CO3)2(HCO3)(A-alpha-SiW9O34)(beta-SiW10O37)].5H3O.18H2O (1) and K6Na4[{Ni6(H2O)4(mu2-H2O)4(mu3-OH)2}(x-SiW9O34)2].17.5H2O (2) have been obtained by reaction of K(8)[gamma-SiW10O36] with NiCl2.2H2O in basic conditions. Compounds 1 and 2 all represent the first polyoxometalates substituted by seven and six Ni centers, respectively. Also, compound 1 exhibits a novel asymmetric dimeric structure, composed of [A-alpha-SiW9O34]10- and [beta-SiW10O37]10- units linked by a Ni7 cluster and three carbonates, which exhibit tri- and bidentate coordination modes in 1.