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  1. Yamamoto T, Tsunematsu Y, Hara K, Suzuki T, Kishimoto S, Kawagishi H, et al.
    Angew Chem Int Ed Engl, 2016 05 17;55(21):6207-10.
    PMID: 27072782 DOI: 10.1002/anie.201600940
    Geometric isomerization can expand the scope of biological activities of natural products. The observed chemical diversity among the pseurotin-type fungal secondary metabolites is in part generated by a trans to cis isomerization of an olefin. In vitro characterizations of pseurotin biosynthetic enzymes revealed that the glutathione S-transferase PsoE requires participation of the bifunctional C-methyltransferase/epoxidase PsoF to complete the trans to cis isomerization of the pathway intermediate presynerazol. The crystal structure of the PsoE/glutathione/presynerazol complex indicated stereospecific glutathione-presynerazol conjugate formation is the principal function of PsoE. Moreover, PsoF was identified to have an additional, unexpected oxidative isomerase activity, thus making it a trifunctional enzyme which is key to the complexity generation in pseurotin biosynthesis. Through the study, we identified a novel mechanism of accomplishing a seemingly simple trans to cis isomerization reaction.
  2. Yu Z, Liu J, Tan CSY, Scherman OA, Abell C
    Angew Chem Int Ed Engl, 2018 03 12;57(12):3079-3083.
    PMID: 29377541 DOI: 10.1002/anie.201711522
    The ability to construct self-healing scaffolds that are injectable and capable of forming a designed morphology offers the possibility to engineer sustainable materials. Herein, we introduce supramolecular nested microbeads that can be used as building blocks to construct macroscopic self-healing scaffolds. The core-shell microbeads remain in an "inert" state owing to the isolation of a pair of complementary polymers in a form that can be stored as an aqueous suspension. An annealing process after injection effectively induces the re-construction of the microbead units, leading to supramolecular gelation in a preconfigured shape. The resulting macroscopic scaffold is dynamically stable, displaying self-recovery in a self-healing electronic conductor. This strategy of using the supramolecular assembled nested microbeads as building blocks represents an alternative to injectable hydrogel systems, and shows promise in the field of structural biomaterials and flexible electronics.
  3. Nanthasurasak P, See HH, Zhang M, Guijt RM, Breadmore MC
    Angew Chem Int Ed Engl, 2019 03 18;58(12):3790-3794.
    PMID: 30614157 DOI: 10.1002/anie.201812077
    An electrokinetic platform was developed for extracting small-molecule pharmaceuticals from a dried blood spot. Through the exclusion of liquid reagents and use of low field strength (6 V cm-1 ), the electroextraction of a drug from a dried blood spot, deposited on a polymer inclusion membrane (PIM), could be realised while in transit in the mail. In transit sample preparation provides a potential solution to in situ sample degradation and may accelerate the workflow upon arrival of a patient sample at the analytical facility. The electroextraction method was enabled through our discovery of the use of 15-20 μm thin PIMs as electrophoretic separation medium in absence of liquid reagents. Here, a PIM consisting of cellulose triacetate as polymer base, 2-nitrophenyl octyl ether as plasticizer and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide as carrier was used. The PIM, was packaged with two 12 V batteries to supply the separation voltage. A blood spot containing berberine chloride was deposited and dried before the applying the separation potential, allowing for the electroextraction while the packaged device was shipped in internal mail. Upon arrival in the analytical laboratory, the PIM was analysed using a fluorescence microscope with photon multiplier tube, quantifying the berberine extracted away from the sample matrix. This platform represents a new opportunity for processing clinical samples during transport to the laboratory, saving time and manual handling to accelerate the time to result.
  4. Wu H, Kong XY, Wen X, Chai SP, Lovell EC, Tang J, et al.
    Angew Chem Int Ed Engl, 2021 Apr 06;60(15):8455-8459.
    PMID: 33368920 DOI: 10.1002/anie.202015735
    Improving the stability of cuprous oxide (Cu2 O) is imperative to its practical applications in artificial photosynthesis. In this work, Cu2 O nanowires are encapsulated by metal-organic frameworks (MOFs) of Cu3 (BTC)2 (BTC=1,3,5-benzene tricarboxylate) using a surfactant-free method. Such MOFs not only suppress the water vapor-induced corrosion of Cu2 O but also facilitate charge separation and CO2 uptake, thus resulting in a nanocomposite representing 1.9 times improved activity and stability for selective photocatalytic CO2 reduction into CH4 under mild reaction conditions. Furthermore, direct transfer of photogenerated electrons from the conduction band of Cu2 O to the LUMO level of non-excited Cu3 (BTC)2 has been evidenced by time-resolved photoluminescence. This work proposes an effective strategy for CO2 conversion by a synergy of charge separation and CO2 adsorption, leading to the enhanced photocatalytic reaction when MOFs are integrated with metal oxide photocatalyst.
  5. Hillman F, Hamid MRA, Krokidas P, Moncho S, Brothers EN, Economou IG, et al.
    Angew Chem Int Ed Engl, 2021 Apr 26;60(18):10103-10111.
    PMID: 33620755 DOI: 10.1002/anie.202015635
    We present a novel synthesis strategy termed delayed linker addition (DLA) to synthesize hybrid zeolitic-imidazolate frameworks containing unsubstituted imidazolate linkers (Im) with SOD topology (hereafter termed Im/ZIF-8). Im linker incorporation can create larger voids and apertures, which are important properties for gas storage and separation. To date, there have been only a handful of reports of Im linkers incorporated into ZIF-8 frameworks, typically requiring arduous and complicated post synthesis approaches. DLA, as reported here, is a simple one-step synthesis strategy allowing high incorporation of Im linker into the ZIF-8 framework while still retaining its SOD topology. We fabricated mixed-matrix membranes (MMMs) with 6FDA-DAM polymer and Im/ZIF-8 obtained via DLA as a filler. The Im/ZIF-8-containing MMMs showed excellent performance for both propylene/propane and n-butane/i-butane separation, displaying permeability and ideal selectivity well above the polymer upper bound. Moreover, highly detailed molecular simulations shed light to the aperture size and flexibility response of Im/ZIF-8 and its improved diffusivity as compared to ZIF-8.
  6. Wang J, Jiang Y, Liu JY, Xu HB, Zhang YX, Peng X, et al.
    Angew Chem Int Ed Engl, 2021 Oct 04;60(41):22368-22375.
    PMID: 34383376 DOI: 10.1002/anie.202107637
    The salts {[Ln2 Ln*(Hhmq)3 (OAc)3 (hfac)2 ]+ [Ln*(hfac)3 (OAc)(MeOH)]- } (Hhmq=2-methanolquinolin-8-oxide, hfac=hexafluoroacetylacetonate; Ln, Ln*=Er, Gd, Yb) feature a discrete heteronuclear cation consisting of two types of lanthanide atoms. The quinolinoxy O-atom serves as a μ2 -bridge to two Ln atoms and as a μ3 -bridge to all three atoms, with metal⋅⋅⋅metal distances being around 3.7 Å. For 1 ([Yb2 Er]+ ), near-infrared downshifted luminescence is switched to competitive upconversion luminescence upon irradiation by a 980 nm laser under an extremely low excitation power (0.288 W cm-2 ) through introduction of fluoride ions. The stability of 1 after addition of fluoride was confirmed by powder X-ray diffraction and multistage mass spectrometry, associated with the 1 H NMR of 6 ([La2 Eu]+ ). More importantly, the at least 20-fold enhancement of the quantum yield in non-deuterated solvents at room temperature under low power densities (2 W cm-2 ) is the highest among the few molecular examples reported.
  7. Nordin N, Bordonali L, Davoodi H, Ratnawati ND, Gygli G, Korvink JG, et al.
    Angew Chem Int Ed Engl, 2021 08 23;60(35):19176-19182.
    PMID: 34132012 DOI: 10.1002/anie.202103585
    Compartmentalized chemical reactions at the microscale are important in biotechnology, yet monitoring the molecular content at these small scales is challenging. To address this challenge, we integrate a compact, reconfigurable reaction cell featuring electrochemical functionality with high-resolution NMR spectroscopy. We demonstrate the operation of this system by monitoring the activity of enzymes immobilized in chemically distinct layers within a multi-layered chitosan hydrogel assembly. As a benchmark, we observed the parallel activities of urease (Urs), catalase (Cat), and glucose oxidase (GOx) by monitoring reagent and product concentrations in real-time. Simultaneous monitoring of an independent enzymatic process (Urs) together with a cooperative process (GOx + Cat) was achieved, with chemical conversion modulation of the GOx + Cat process demonstrated by varying the order in which the hydrogel was assembled.
  8. Liu J, Tan CSY, Scherman OA
    Angew Chem Int Ed Engl, 2018 07 16;57(29):8854-8858.
    PMID: 29663607 DOI: 10.1002/anie.201800775
    Supramolecular building blocks, such as cucurbit[n]uril (CB[n])-based host-guest complexes, have been extensively studied at the nano- and microscale as adhesion promoters. Herein, we exploit a new class of CB[n]-threaded highly branched polyrotaxanes (HBP-CB[n]) as aqueous adhesives to macroscopically bond two wet surfaces, including biological tissue, through the formation of CB[8] heteroternary complexes. The dynamic nature of these complexes gives rise to adhesion with remarkable toughness, displaying recovery and reversible adhesion upon mechanical failure at the interface. Incorporation of functional guests, such as azobenzene moieties, allows for stimuli-activated on-demand adhesion/de-adhesion. Macroscopic interfacial adhesion through dynamic host-guest molecular recognition represents an innovative strategy for designing the next generation of functional interfaces, biomedical devices, tissue adhesives, and wound dressings.
  9. Clavadetscher J, Hoffmann S, Lilienkampf A, Mackay L, Yusop RM, Rider SA, et al.
    Angew Chem Int Ed Engl, 2016 12 12;55(50):15662-15666.
    PMID: 27860120 DOI: 10.1002/anie.201609837
    The copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction has proven to be a pivotal advance in chemical ligation strategies with applications ranging from polymer fabrication to bioconjugation. However, application in vivo has been limited by the inherent toxicity of the copper catalyst. Herein, we report the application of heterogeneous copper catalysts in azide-alkyne cycloaddition processes in biological systems ranging from cells to zebrafish, with reactions spanning from fluorophore activation to the first reported in situ generation of a triazole-containing anticancer agent from two benign components, opening up many new avenues of exploration for CuAAC chemistry.
  10. Zhang W, Mohamed AR, Ong WJ
    Angew Chem Int Ed Engl, 2020 Dec 14;59(51):22894-22915.
    PMID: 32009290 DOI: 10.1002/anie.201914925
    Transforming CO2 into fuels by utilizing sunlight is promising to synchronously overcome global warming and energy-supply issues. It is crucial to design efficient photocatalysts with intriguing features such as robust light-harvesting ability, strong redox potential, high charge-separation, and excellent durability. Hitherto, a single-component photocatalyst is incapable to simultaneously meet all these criteria. Inspired by natural photosynthesis, constructing artificial Z-scheme photocatalysts provides a facile way to conquer these bottlenecks. In this review, we firstly introduce the fundamentals of photocatalytic CO2 reduction and Z-scheme systems. Thereafter we discuss state-of-the-art Z-scheme photocatalytic CO2 reduction, whereby special attention is placed on the predominant factors that affect photoactivity. Additionally, further modifications that are important for efficient photocatalysis are reviewed.
  11. Wang C, Pang Y, Wu Y, Zhang N, Yang R, Li Y, et al.
    Angew Chem Int Ed Engl, 2021 12 20;60(52):26978-26985.
    PMID: 34665909 DOI: 10.1002/anie.202110149
    A divergent synthesis of skeletally distinct arboridinine and arborisidine was achieved. The central divergent strategy was inspired by the divergent biosynthetic cyclization mode of arboridinine and arborisidine and their hidden topological connection. The branch point was reached through a Michael and Mannich cascade process. A site-selective intramolecular Mannich reaction was developed to construct the tetracyclic core of arboridinine, while a site-selective intramolecular α-amination of ketone was used to access the tetracyclic core of arborisidine. A strategic Peterson olefination through intramolecular nucleophile delivery was able to set up the exocyclic olefin of arboridinine.
  12. Wang K, Han C, Li J, Qiu J, Sunarso J, Liu S
    Angew Chem Int Ed Engl, 2022 Feb 01;61(6):e202110429.
    PMID: 34612568 DOI: 10.1002/anie.202110429
    Piezocatalysis, a newly emerging catalysis technology that relies on the piezopotential and piezoelectric properties of the catalysts, is attracting unprecedented research enthusiasm for applications in energy conversion, organic synthesis, and environmental remediation. Despite the rapid development in the past three years, the mechanism of piezocatalysis is still under debate. A fundamental understanding of the working principles of this technology should enable the future design and optimization of piezocatalysts. Herein, we provide an overview of the two popular theories used to explain the observed piezocatalysis: energy band theory and screening charge effect. A comprehensive discussion and clarification of the differences, relevance, evidence, and contradiction of the two mechanisms are provided. Finally, challenges and perspectives for future mechanistic studies are highlighted. Hopefully, this Review can help readers gain a better understanding of piezocatalysis and enable its application in their own research.
  13. Xiong J, Zhou PJ, Jiang HW, Huang T, He YH, Zhao ZY, et al.
    Angew Chem Int Ed Engl, 2021 Oct 04;60(41):22270-22275.
    PMID: 34374477 DOI: 10.1002/anie.202109082
    Forrestiacids A (1) and B (2) are a novel class of [4+2] type pentaterpenoids derived from a rearranged lanostane moiety (dienophile) and an abietane unit (diene). These unprecedented molecules were isolated using guidance by molecular ion networking (MoIN) from Pseudotsuga forrestii, an endangered member of the Asian Douglas Fir Family. The intermolecular hetero-Diels-Alder adducts feature an unusual bicyclo[2.2.2]octene ring system. Their structures were elucidated by spectroscopic analysis, GIAO NMR calculations and DP4+ probability analyses, electronic circular dichroism calculations, and X-ray diffraction analysis. This unique addition to the pentaterpene family represents the largest and the most complex molecule successfully assigned using computational approaches to predict accurately chemical shift values. Compounds 1 and 2 exhibited potent inhibitory activities (IC50 s <5 μM) of ATP-citrate lyase (ACL), a new drug target for the treatment of glycolipid metabolic disorders including hyperlipidemia. Validating this activity 1 effectively attenuated the de novo lipogenesis in HepG2 cells. These findings provide a new chemical class for developing potential therapeutic agents for ACL-related diseases with strong links to traditional medicines.
  14. Urbina-Blanco CA, Jilani SZ, Speight IR, Bojdys MJ, Friščić T, Stoddart JF, et al.
    Angew Chem Int Ed Engl, 2020 Oct 12;59(42):18306-18310.
    PMID: 33448562 DOI: 10.1002/anie.202009834
    Valuing diversity leads to scientific excellence, the progress of science and most importantly, it is simply the right thing to do. We can value diversity not only in words, but also in actions.
  15. Zhan SZ, Liu YL, Cai H, Li MD, Huang Q, Wang XD, et al.
    Angew Chem Int Ed Engl, 2023 Oct 23;62(43):e202312698.
    PMID: 37682089 DOI: 10.1002/anie.202312698
    The first coordination-saturated buckyball with a C60 molecule totally encased in an icosidodecahedral Cu30 in a (μ30 -(η2 )30 )-fashion, namely C60 @Cu30 @Cl36 N12 , has been successfully realized by a C60 -templated assembly. The 48 outmost coordinating atoms (36Cl+12N) comprise a new simple polyhedron that is described by a ccf topology. Charge transfer from (CuI , Cl) to C60 explains the expansion of the light absorption up to 700 nm, and accounts for an ultrafast photophysical process that underpins its high photothermal conversion efficiency. This work makes a giant step forward in exohedral metallofullerene (ExMF) chemistry.
  16. Liu YL, Zhan SZ, Sun JX, Cai H, Yuan ZL, Zhang HF, et al.
    Angew Chem Int Ed Engl, 2023 Aug 14;62(33):e202306748.
    PMID: 37366116 DOI: 10.1002/anie.202306748
    Two metallofullerene frameworks (MFFs) constructed from a penta-shell Keplerate cuprofullerene chloride, C60 @Cu24 @Cl44 @Cu12 @Cl12 , have been successfully prepared via a C60 -templated symmetry-driven strategy. The icosahedral cuprofullerene chloride is assembled on a C60 molecule through [η2 -(C=C)]-CuI and CuI -Cl coordination bonds, resulting in the penta-shell Keplerate with the C60 core canopied by 24 Cu, 44 Cl, 12 Cu and 12 Cl atoms that fulfill the tic@rco@oae@ico@ico penta-shell polyhedral configuration. By sharing the outmost-shell Cl atoms, the cuprofullerene chlorides are connected into 2D or 3D (snf net) frameworks. TD-DFT calculations reveal that the charge transfer from the outmost CuI and Cl to C60 core is responsible for their light absorption expansion to near-infrared region, implying anionic halogenation may be an effective strategy to tune the light absorption properties of metallofullerene materials.
  17. Abu Bakar R, Hepburn KS, Keddie JL, Roth PJ
    Angew Chem Int Ed Engl, 2023 Aug 21;62(34):e202307009.
    PMID: 37378955 DOI: 10.1002/anie.202307009
    Pressure-sensitive adhesives (PSAs) are made from soft, irreversibly lightly crosslinked polymers. Even after removal from surfaces, they retain insoluble networks which pose problems during the recycling of glass and cardboard. Herein, degradable PSAs are presented that provide the required performance in use but have networks that can be degraded after use. A series of copolymers was prepared through radical copolymerization of n-butyl acrylate, 4-acryloyloxy benzophenone (ABP) photo-crosslinker, and dibenzo[c,e]oxepin-5(7H)-thione (DOT) to provide degradable backbone thioesters. The optimum tack and peel strengths were found for molar contents of 0.05 mol% ABP and 0.25 mol% DOT. Degradation of the backbone thioesters through aminolysis or thiolysis led to the full dissolution of the networks, loss of adhesive properties of films (decreases in the measured tack and peel strengths), and the quick detachment of model labels from a substrate. Inclusion of DOT into PSAs offers a viable route toward degradable and recyclable packaging labels.
  18. Yang R, Zhou Z, Jiang H, Kam TS, Chen K, Ma Z
    Angew Chem Int Ed Engl, 2024 Jan 15;63(3):e202316016.
    PMID: 38038685 DOI: 10.1002/anie.202316016
    The first asymmetric total synthesis of the monoterpenoid indole alkaloid arboduridine has been accomplished. The tricyclic A/B/D ring system was constructed by an enantioselective Michael reaction followed by intramolecular nucleophilic addition. Intramolecular α-amination of a ketone forged the piperidine ring, while a Horner-Wadsworth-Emmons (HWE) reaction was used to form the pyrrolidine ring. A reduction cyclization cascade led to formation of the tetrahydrofuran ring.
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