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Single‐crystal‐to‐single‐crystal (SCSC) transformations of porous crystals have been proved as an important platform for creating new materials. The current study describes porous molecular crystal with two different polymorphs based on the same chiral helicate modules can be controllably obtained when simply changing the crystallization solvents from diethyl ether to isopropyl ether. Interestingly, the β‐polymorph can also be effective obtained through SCSC transformations from α‐polymorph in solid state using isopropanol as a trigger. Compared with our reported α‐polymorph, the newly obtained β‐polymorph porous molecular crystal displays higher CO2 uptake and better selectivity for CO2 over N2 at 298 K. Meanwhile, as chiral solid adsorbents, both of β‐polymorph and α‐polymorph exhibit similar enantioselective separation abilities towards alcohols but different adsorption kinetics. [ABSTRACT FROM AUTHOR]

• Discussing the superiorities of supramolecular coordination complexes (SCCs) in anticancer filed. • Presenting recent progress of Pt(II), Ru(II), and Ir(III)-based SCCs for intensive cancer therapy. • Concluding regulatory factors for further structure design, and presenting challenges and promising strategies. The development of highly efficient and minimally toxic agents with targeting abilities toward tumor tissues is an ongoing area of research in the fight against cancer. Different from the mononuclear and multinuclear metallodrug complexes, impressively, the unique supramolecular coordination complexes (SCCs) have shown great superiority in cancer treatment. The vast combinational flexibility of ligands and metal ions offers limitless opportunities to form desired SCCs, thus endows them with distinct, captivating and integrated biological and chemical properties. Compared to organic drugs that are predominantly one-dimensional (1D) or two-dimensional (2D) in shape, the structurally much more complicated three-dimensional (3D) multinuclear assemblies with elaborate sizes, shapes, or cavities can exhibit unexpected binding sensitivity and selectivity toward biomolecules. Over the last decades, significant progress has been made in the design and synthesis of novel SCCs for intensive cancer therapy. These assemblies have been formulated using new strategies and formulations, resulting in nonclassical action modes that show promising results. This review aims at gathering innovative multinuclear Pt(II), Ru(II), and Ir(III)-based metallo-assemblies as promising anticancer drugs. Each section is divided into different parts based on the number of metal ions and shapes of the assembly. Furthermore, the review concludes with an exploration of the regulatory factors of structure design and discusses the perspectives for the practical impact of this type of research in medicinal chemistry. It is expected that this review will afford important guidance for the further development of these promising anticancer agents in biological applications, resulting in innovative anticancer agents that continue along this already promising path. [ABSTRACT FROM AUTHOR]

A bimetallic Cu(II) complex as a novel antitumor chemodynamic therapy agent with glutathione (GSH) depletion properties is successfully synthesized and well characterized. In tumor cells, the Cu2+ ions of the complex are reduced to Cu+ ions by GSH and then catalyzed by the overexpressed H2O2 to generate highly cytotoxic hydroxyl radicals (˙OH) that kill cancer cells. The complex is quickly taken up by cancer cells and distributed in multiple organelles including mitochondria and the nucleus. The complex demonstrates good cytotoxicity toward various cancer cell lines. However, its toxicity toward normal cells is significantly lower than that toward cancer cells due to the limited expression of H2O2. In addition, the complex could arrest the cell cycle of the G0/G1 phase, thereby inducing apoptosis rather than necrosis. [ABSTRACT FROM AUTHOR]

The design of novel agents that specifically target DNA and interrupt its normal biological processes is an attractive goal in drug design. Among the promising metallodrugs, metal-directed self-assembled metallohelices with defined three-dimensional stereochemical structures display unique structure-inherent and unprecedented noncovalent targeting abilities towards DNA, resulting in excellent anticancer or antibiotic activities. A newly burgeoning hotspot is focusing on lighting them up by embedding luminescent metal ions as the vertices. The photoactive metallohelices that combine strong interactions toward DNA targets and efficient 1O2 quantum yield may provide new motivation in diagnostic and photodynamic therapy (PDT) areas. This perspective focuses on research progress on metallohelices as DNA binders and chemotherapeutic agents, and highlights recent advances in fabricating luminescent examples for PDT. The relative assembly strategies are also discussed and compared. Finally, perspectives on the future development of the lit-up metallohelices are presented. [ABSTRACT FROM AUTHOR]

The development of DNA‐targeted photodynamic therapy (PDT) agents for cancer treatment has drawn substantial attention. Herein, the design and synthesis of dinuclear IrIII‐containing luminescent metallohelices with tunable PDT efficacy that target mitochondrial DNA in cancer cells are reported. The metallohelices are fabricated using dynamic imine‐coupling chemistry between aldehyde end‐capped fac‐Ir(ppy)3 handles and linear alkanediamine spacers, followed by reduction of the imine linkages. The length and odd–even character of the diamine alkyl linker determined the stereochemistry (helicates vs. mesocates). Compared to the helicates, the mesocates exhibit improved apoptosis‐induction upon white‐light irradiation. Molecular docking studies indicate that the mesocate with a proper length of diamine spacers shows stronger affinity for the minor groove of DNA. This study highlights the potential of DNA‐targeting IrIII‐containing metallohelices as PDT agents. [ABSTRACT FROM AUTHOR]

The development of DNA‐targeted photodynamic therapy (PDT) agents for cancer treatment has drawn substantial attention. Herein, the design and synthesis of dinuclear IrIII‐containing luminescent metallohelices with tunable PDT efficacy that target mitochondrial DNA in cancer cells are reported. The metallohelices are fabricated using dynamic imine‐coupling chemistry between aldehyde end‐capped fac‐Ir(ppy)3 handles and linear alkanediamine spacers, followed by reduction of the imine linkages. The length and odd–even character of the diamine alkyl linker determined the stereochemistry (helicates vs. mesocates). Compared to the helicates, the mesocates exhibit improved apoptosis‐induction upon white‐light irradiation. Molecular docking studies indicate that the mesocate with a proper length of diamine spacers shows stronger affinity for the minor groove of DNA. This study highlights the potential of DNA‐targeting IrIII‐containing metallohelices as PDT agents. [ABSTRACT FROM AUTHOR]

By introducing photoactive fac-tris(2-phenylpyridine)iridium moieties as a ligand backbone to constrain the coordination geometry of cobalt ions, a multifunctional Ir2Co3-type capsule was achieved and showed induced-fit capsule–capsule conversion by cooperative binding one carbonate anion with the equatorial Co(ii) centers. The capsule combined photocatalysis and transition metal activation synergistically and exhibited efficient catalytic ability on visible light-activated α-trichloromethylation. [ABSTRACT FROM AUTHOR]

By incorporating a fac-tris(4-(2-pyridinyl)phenylamine)iridium as the backbone of the tripodal ligand to constrain the coordination geometry of Zn(ii) ions, a pentanuclear Ir–Zn heterometal–organic luminescent polyhedron was obtained via a subcomponent self-assembly for carbon dioxide fixation and sulfite sequestration. [ABSTRACT FROM AUTHOR]

Conventional hydrothermal synthesis of titanate nanotubes (TNTs) by P25 TiO 2 and NaOH has been blamed for its long reaction time (continuous heating for three days). This paper presented a short-cut hydrothermal synthesis of TNTs by nano-anatase and NaOH, which significantly reduced the reaction time from 72 to 6 h while the other experimental conditions were same. Essential interpretation of such a surprising reduction of reaction time was given in terms of TEM, XRD and FTIR analysis. It indicates that the transformation from anatase to sodium tri-titanate nanotubes includes the following three steps: (1) aggregation of spherical anatase particles (0–1 h), (2) morphologic transformation to titanate nanosheets with fewer visible anatase crystal arrays (1–3 h), and (3) crimping of tri-titanate nanosheets and a final generation of TNTs (3–6 h). Further comparison with TNTs synthesis process from P25 TiO 2 (ca. 80% of anatase and 20% of rutile) indicates that the rate-limiting step for breakage of Ti–O–Ti bond is largely controlled by crystal array of the concerned nanomaterials. The as-prepared TNTs are proved to exhibit similar Cd adsorption capacity compared with conventional TNTs based on batch adsorption experiments. The widely distributed anatase in nature as well as its over 90% reaction time saving in TNTs preparation process under facile conditions makes the proposed short-cut synthesis of great potential in engineering applications. [ABSTRACT FROM AUTHOR]

Supramolecular artificial light‐harvesting system with highly efficient host–guest energy transfer pathway provides an ideal platform for optimizing the photochemistry process. The consecutive photo‐induced electron transfer (conPET) process overcomes the energy limitation of visible‐light photocatalysis, but is often compromised by mismatching between the absorption of ground state dye and its radical, weakening the efficiency of photoredox reaction. By encapsulating a conPET photocatalyst rhodamine 6G into metal‐organic cage, the supramolecular approach was undertaken to tackle the intrinsic difficulty of matching the light absorption of photoexcitation between rhodamine 6G and its radical. The highly efficient Förster resonance energy transfer from the photoexcited cage to rhodamine 6G forced by host–guest encapsulation facilitates the conPET process for the single‐wavelength light‐driven activation of aryl halides by stabilizing and accelerating the production and accumulation of the rhodamine 6G radical intermediate. The tunable and flexible nature of the supramolecular host–guest complex renders the cage‐based encapsulation strategy promising for the development of ideal photocatalysts toward the better utilization of solar energy. [ABSTRACT FROM AUTHOR]

Blocking cancer metabolism represents an attractive therapeutic strategy for cancer treatment. However, the lack of selective mitochondria targeting compromises the efficacy and safety of antimetabolic agents. Given that β‐glucuronidase (β‐G) is overexpressed in the tumor extracellular microenvironment and intracellular endosomes and lysosomes, a new concept of "pro‐staramine" is proposed to achieve multistage tumor mitochondrial targeting. The pro‐staramine, namely GluAcNA, is engineered by conjugating a β‐glucuronic acid to staramine via a "seamless" linker. When exposed to β‐G, the β‐glucuronic acid in GluAcNA can be hydrolyzed, followed by a rapid 1,6‐self‐elimination of the "seamless", thus transforming anionic GluAcNA to cationic staramine. Liposomes containing GluAcNA (GluAcNA‐Lip) show long‐circulating characteristics and undergo a sequentially β‐G‐triggered activation, resulting in a cation‐driven mitochondrial accumulation. The multistage mitochondrial targeting and the promising antitumoral efficacy of GluAcNA‐Lip are validated by employing lonidamine as a model drug. [ABSTRACT FROM AUTHOR]

The design of artificial systems that mimic highly evolved and finely tuned natural photosynthetic systems is a subject of intensive research. By incorporating electron‐deficient anthraquinone within the ligand backbone, a redox‐active Ni‐based tetrahedron was developed as a redox vehicle for the construction of an artificial photosynthesis system. The tetrahedron can encapsulate fluorescein within its cavity for light‐driven H2 evolution, with the turnover number reaching 1200 moles H2 per mole redox catalyst. This well‐designed supramolecular system displayed a significantly superior activities compared with the reference mononuclear compound or introducing an inactive inhibitor (ATP), which confirmed this enzymatic photocatalytic behaviour. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Thermodynamic constraints within the pockets of Werner-type capsules. • Dynamic behaviors within the pockets of Werner-type capsules. • Electron transfer and photosynthesis within the confined spaces of Werner-type capsules. Abstract The use of small molecules with defined cavities that catalyze unique chemical transformations to emulate enzyme sites have resulted in sustainable catalytic transformation with unprecedented selectivity that proceed under ambient conditions using benign solvents and clean energy. Of these reported host molecules, Werner-type capsules have been of particular interest to researchers because of their structural modifiability and rich chemical properties arising from their uniform cavities. In this review, we focus on the catalytic properties of several important catalytic transformations that have occurred within the confined pockets of these Werner-type capsules with special attention to the aspects that are derived from the 'confined space effect' of these Werner-type capsules. [ABSTRACT FROM AUTHOR]

Conventional photocages only respond to short wavelength light, which is a significant obstacle to developing efficient phototherapy in vivo. The development of photocages activated by near‐infrared (NIR) light at wavelengths from 700 to 950 nm is important for in vivo studies but remains challenging. Herein, we describe the synthesis of a photocage based on a ruthenium (Ru) complex with NIR light‐triggered photocleavage reaction. The commercial anticancer drug, tetrahydrocurcumin (THC), was coordinated to the RuII center to create the Ru‐based photocage that is readily responsive to NIR light at 760 nm. The photocage inherited the anticancer properties of THC. As a proof‐of‐concept, we further engineered a self‐assembled photocage‐based nanoparticle system with amphiphilic block copolymers. Upon exposure to NIR light at 760 nm, the Ru complex‐based photocages were released from the polymeric nanoparticles and efficiently inhibited tumor proliferation in vivo. [ABSTRACT FROM AUTHOR]

Conventional photocages only respond to short wavelength light, which is a significant obstacle to developing efficient phototherapy in vivo. The development of photocages activated by near‐infrared (NIR) light at wavelengths from 700 to 950 nm is important for in vivo studies but remains challenging. Herein, we describe the synthesis of a photocage based on a ruthenium (Ru) complex with NIR light‐triggered photocleavage reaction. The commercial anticancer drug, tetrahydrocurcumin (THC), was coordinated to the RuII center to create the Ru‐based photocage that is readily responsive to NIR light at 760 nm. The photocage inherited the anticancer properties of THC. As a proof‐of‐concept, we further engineered a self‐assembled photocage‐based nanoparticle system with amphiphilic block copolymers. Upon exposure to NIR light at 760 nm, the Ru complex‐based photocages were released from the polymeric nanoparticles and efficiently inhibited tumor proliferation in vivo. [ABSTRACT FROM AUTHOR]

Highlights: [•] Titanate transformed into anatase but not rutile via wet chemical reaction. [•] The transition process was an in situ rearrangement of unit structure [TiO6]. [•] Modified TNTs showed both high photocatalytic and adsorptive performance. [•] Modified TNTs could simultaneously remove heavy metals and organic pollutants. [Copyright &y& Elsevier]

Inside Back Cover: A Near-Infrared Light-Activated Photocage Based on a Ruthenium Complex for Cancer Phototherapy (Angew. The photocage was engineered into amphiphilic block copolymers, forming nanoparticles via self-assembly, which release the ruthenium complex-based photocages to inhibit tumor proliferation in vivo upon exposure to NIR light. Photocages, Ruthenium complex, NIR light, Polymer nanoparticles, Photocleavage reaction. [Extracted from the article]

Photocages, Ruthenium complex, NIR light, Polymer nanoparticles, Photocleavage reaction Keywords: Photocages; Ruthenium complex; NIR light; Polymer nanoparticles; Photocleavage reaction EN Photocages Ruthenium complex NIR light Polymer nanoparticles Photocleavage reaction 1 1 1 06/06/23 20230612 NES 230612 B A ruthenium-based photocage b that can be activated by 760 nm NIR light via single-photon pathway is reported by Xuezhao Li, Wen Sun et al. in their Research Article (e202218768). The photocage was engineered into amphiphilic block copolymers, forming nanoparticles via self-assembly, which release the ruthenium complex-based photocages to inhibit tumor proliferation in vivo upon exposure to NIR light. [Extracted from the article]

Abstract: Adsorption of Pb2+, Cd2+, Cu2+ and Cr3+ from aqueous solutions onto titanate nanotubes (TNTs) in multiple systems was systematically studied. Particular attention was paid to competitive adsorption and the effect of inorganic ions. TNTs showed large adsorption capacity for the four heavy metals, with the mechanism of ion-exchange between metal ions and H+/Na+ located in the interlayers of TNTs. Binary or quaternary competitive adsorption indicated that the adsorption capacity of the four heavy metals onto TNTs followed the sequence of Pb2+ (2.64mmolg−1)≫Cd2+ (2.13mmolg−1)>Cu2+ (1.92mmolg−1)≫Cr3+ (1.37mmolg−1), which followed the reverse order of their hydration energies. Moreover, inorganic ions including Na+, K+, Mg2+ and Ca2+ inhibited the adsorption of heavy metals on TNTs, because they competed for adsorption sites, decreased the activity of heavy metal ions, and promoted the aggregation of TNTs. However, Al3+ and Fe3+ generally enhanced adsorption because the resulting hydroxyl-Al/Fe intercalated or coated TNTs could also capture metal ions. Furthermore, minor effect of inorganic ions on adsorption of Pb2+ resulted from its strong affinity to TNTs. Difficult desorption and small inhibiting effect by Na+, K+, Mg2+ and Ca2+ on adsorption of Cr3+ was due to the formed stable complex of HOCr(OTi)2 with TNTs. Present study indicated potential applications of TNTs in wastewater treatment for heavy metals. [Copyright &y& Elsevier]

Abstract: A dye-functionalized silica nanomaterial, SBA-RT was prepared by the immobilization of the Rhodamine-based chemosensor R6G-TETA within the channels of SBA-15. SBA-RT exhibits several different properties compared to the free R6G-TETA, such as higher selectivity, blue-shift of the UV–vis spectra due to special spatial environment in the channels of the mesoporous material. It presents Cr(III)-selective fluorimetric and colorimetric responses in aqueous solution. The fluorescence responses are reversible by treating with EDTA and do not vary over a broad pH range suitable for Cr(III) bioimaging application. Through isolating of the metal ions within the mesopores of the silica, SBA-RT can extract Cr(III) from the solution with only trace amounts remaining. The fluorescence images experiment demonstrated the possibility of further application in monitoring Cr(III) in living cells and organisms. [Copyright &y& Elsevier]

Photodynamic therapy (PDT) is clinically promising in destructing primary tumors but ineffective against distant metastases. This study reports the use of immunogenic nanoparticles mediated combination of PDT and magnetic hyperthermia to synergistically augment the anti‐metastatic efficacy of immunotherapy. Janus nanobullets integrating chlorine e6 (Ce6) loaded, disulfide‐bridged mesoporous organosilica bodies with magnetic heads (M‐MONs@Ce6) are tailored for redox/pH‐triggered photosensitizer release accompanying their matrix degradation. Cancer cell membrane cloaking enables favorable tumor‐targeted accumulation and prolonged blood circulation time of M‐MONs@Ce6. The combination of PDT and magnetic hyperthermia has a strong synergy anticancer activity and simultaneously elicits a sequence of immunogenic cell death, resulting in synergistically tumor‐specific immune responses. When combined with anti‐CTLA‐4 antibody, the biomimetic and biodegradable nanoparticle enables the notable eradication of primary and deeply metastatic tumors with low systematic toxicity, thus potentially advancing the development of combined hyperthermia, PDT, and checkpoint blockade immunotherapy to combat cancer metastasis. [ABSTRACT FROM AUTHOR]