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The problem with metal–organic frameworks (MOFs) as CO2-epoxide cycloaddition catalysts is the ambiguous catalytic sites. No system can precisely modify the structures and thus optimize the catalytic performance. Reticular chemistry is recognized as an efficient approach to systematically control the chemical and structural features as well as the properties of porous, crystalline materials. In this work, a Zn-phosphonocarboxylate framework (ZnPC-2) was employed as a prototype structure to investigate the structure–property relationship (SPR). ZnPC-2 is a porous rutile-type framework constructed by 6-connected Zn3(PO3)2(CO2)4 secondary building unit (Zn3-SBU) and tritopic 5-phosphonobenzene-1,3-dicarboxylic acid (H4pbdc). ZnPC-2 showed the ability to catalyze the CO2 cycloaddition reactions and Zn3-SBU was proved as efficient catalytic site. Guided by reticular chemistry, a series of iso-reticular frameworks, including Hpyr@ZnPC-2 (Hpyr = protonated pyrrolidine, Hpyr is fixed by hydrogen bonding interactions to participate the channel into segments); MZnPC-2 (M = Mg, Mn, Fe, Co, Cu; Zn(II) atoms on Zn3-SBU were partially replaced by M) and ZnPC-2-im (im = imidazole, im coordinates to the apical Zn(II) on Zn3-SBU), were designed and successfully synthesized to explore the precise active site. The catalytic performances over these iso-structures together with density functional theory calculations revealed that the dynamical transformation of the apical Zn (II) on Zn3-SBU from tetrahedral geometry to five coordinated model played the pivotal role during the catalytic process.

Breast cancer is the cancer with the highest incidence all over the world. Phosphatidylinositol 3-kinase is an important regulator of intracellular signaling pathways, which is frequently mutated and overexpressed in majority of human breast cancers, and the inhibition of PI3K has been considered as a promising approach for the treatment of the cancer. Here, we report our design and synthesis of new 7-azaindole derivatives as PI3K inhibitors through the scaffold hopping strategy. By varying the groups at the 3-position of 7-azaindole, we identified a series of potent PI3K inhibitors, whose antiproliferative activities against two human breast cancer MCF-7 and MDA-MB-231 cell lines were evaluated. Representative derivatives FD2054 and FD2078 showed better activity than BKM120 in antiproliferation, reduced the levels of phospho-AKT and induced cell apoptosis. All these results suggested that FD2054 and FD2078 are potent PI3K inhibitors that could be considered as potential candidates for the development of anticancer agents.

Based on indole scaffold, a potent and selective phosphoinositide 3-kinase delta (PI3Kδ) inhibitor, namely FD223, was developed by the bioisosteric replacement drug discovery approach and studied for the treatment of acute myeloid leukemia (AML). In vitro studies revealed that FD223 displays high potency (IC50 = 1 nM) and selectivity (29–51 fold over other PI3K isoforms) against PI3Kδ, and exhibits efficient inhibition of the proliferation of AML cell lines (MOLM-16, HL-60, EOL-1 and KG-1) by suppressing p-AKT Ser473 thus causing G1 phase arrest during the cell cycle. Further given the favorable pharmacokinetic (PK) profiles of FD223, in vivo studies were evaluated using xenograft model in nude mice, confirming its significant antitumor efficacy meanwhile with no observable toxicity. All these results are comparable to the positive group of Idelalisib (CAL-101), indicating that FD223 has potential for further development as a promising PI3Kδ inhibitor for the treatment of leukemia such as AML.

Cinnoline is a potential pharmacophore which has rarely been reported for uses as PI3K inhibitors. In this study, a series of cinnoline derivatives were developed as PI3K inhibitors and evaluated for enzymatic and cellular activities. Most compounds displayed nanomolar inhibitory activities against PI3Ks, among which 25 displayed high LLE and micromolar inhibitory potency against three human tumor cell lines (IC50 = 0.264 μM, 2.04 μM, 1.14 μM).

In this paper, UiO-66 nanoparticles have been facilely prepared in a continuous flow microreactor, in which the particle size can be tuned from hundreds to dozens of nanometers by controlling of the residence time. All the products have been completely characterized by FT-IR, PXRD, N 2 sorption, SEM and TEM. Furthermore, NH 2 -functionalized nano-UiO-66 particles have also been prepared and the drug delivery behavior for 5-fluorouracil (5-Fu) was studied in PBS solution.

A novel phosphonocarboxylic ligand, 4′-phosphonobiphenyl-3,5-dicarboxylic acid (H4pbpdc), was synthesized to construct 4 zinc compounds, namely, {[Zn3(pbpdc)2·2R}n (R = C5H12N for 1, C4H10N for 2 and C6H16N for 3) and {[Zn2pbpdc]·C6H18N3}n(4), which were characterized by X-ray crystallography, elemental analysis, FTIR and TG. Structures 1 ~ 3 have the same 3-dimensional (3-D) frameworks with point symbol of {4.6.73.8}2{42.6.72.8}2{42.62.7.8}2{42.62.72}. Structure 4 is constructed from a 6-connected metallic cluster and 3-connected phosphonocarboxylic building units resulting in a topology of flu-3,6-C2/c. The luminescent properties of compounds 1 ~ 4 and organic ligand were studied.

Four metal phosphonate hybrid compounds, [Pb(Hpbc)] (1), [Pb3(pbc)2(H2O)2] (2), [Cd(H2pbc)2(H2O)2] (3) and [Cd1.5(pbc)(H2O)1.5] · 0.5H2O (4) (H3pbc = 3-phosphono-benzoic acid) were successfully synthesized by the hydrothermal/solvothermal reaction of metal acetate and 3-phosphono-benzoic acid. Compounds 1–4 were pH-dependent products and characterized by elemental analysis, Fourier transform infrared (FT-IR) spectra and single-crystal X-ray diffraction studies. Compound 1 is a two-dimensional (2D) structure constructed by inorganic layer and organic pendant. With the increase of pH value, structure 2 shows 3D inorganic framework with distributing organic moieties in the channels. In 3, the Cd2O10 dimers are linked by alternating terminal and bridging ligands, resulting in 1D chain structure. Compound 4 is a 2D structure where the 1D inorganic chains are connected by the organic moieties of the ligands.

A highly efficient air-initiated hydrosilylation of unactivated alkynes and alkenes and dehalogenation of halohydrocarbons with tris(trimethylsilyl)silane ((TMS)3SiH) as a reducing agent has been established under solvent-free conditions. These observations demonstrate that the potential and versatility of air to function as a competent initiator for Si–H bond activations. It can rival organic initiators and metal catalysts in its efficiency and is a superior initiating system from economic, environmentally sound and practical perspectives.

The reaction of the osmium–antimony cluster Os3(μ-H)(μ-SbPh2)(μ3,η2-C6H4)(CO)9 with AsPh3 at room temperature afforded the o-phenylene cluster Os3(μ-H)(SbPh2)(μ2,η2-C6H4)(CO)9(AsPh3) by nucleophilic addition via a metal–metal bond cleavage, and the substitution product Os3(μ-H)(SbPh2)(μ3,η2-C6H4)(CO)8(AsPh3). It reacted with tBuNC to afford the adduct Os3(μ-H)(SbPh2)(μ2,η2-C6H4)(CO)9(CNtBu) quantitatively. This adduct isomerised slowly on standing via migration of the isonitrile, while photolysis led to decarbonylation to Os3(μ-H)(SbPh2)(μ2,η2-C6H4)(CO)8(CNtBu). All the products have been characterised completely, including by X-ray crystallography, and their structures exhibit very long Os–Os bonds.

Three homochiral metal–organic frameworks ( MOF s) based on enantiopure chiral ligand: (R)-2,2’-dimethoxy-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-3,3′-dicarboxylic acid ( H 2 L ), namely Cd( L )(Py) 3 1 , Cu( L )(Py) 3 2 , Na[Cd( L )( LH )] · 2.5H 2 O 3 (Py = pyridine), were firstly synthesized, under solvothermal reactions. X-ray single-crystal diffraction studies reveal that 1 and 2 adopt one-dimensional (1D) infinite helical structures, while 3 possesses 2D chiral framework structure adopting ABAB offset stacking modes along the a -axis. Thermogravimetric analyses ( TGA ) display that 3 is thermally stable to 330 °C which is rare for homochiral MOF s.