Bread and circuses (c. AD 70–80)

Roman London was enlarged and enhanced in the years immediately following Vespasian’s accession in ways that corresponded with the known ideological goals of the new Flavian regime. As a consequence the city came to be characterized by an imperial architecture of ‘bread and circuses’. This involved the construction of a new amphitheatre for the conduct of games associated with the imperial cult and as the likely site of public executions. Watermills drawing on the latest engineering technology were installed to allow the large-scale preparation of flour to supply local bakeries. Early Flavian investment also involved the creation of new administrative facilities, perhaps including a mansio in Southwark, and new urban districts allowing military and veteran settlement. Cycles of subsequent investment hint at a correlation between building programmes in London and preparations for new campaigns of advance launched on the arrival of new provincial governors.

Large-Scale Preparation of Low-Cost Nonfullerene Acceptors for Stable and Efficient Organic Solar Cells

Despite the development of nonfullerene acceptors (NFAs) that have made a breakthrough in the photovoltaic performance, large-scale preparation of NFAs that is prerequisite for commercial application has never been explored. Herein, we designed two dodecacyclic all-fused-ring electron acceptors, F11 and F13, and develop a whole set of synthetic procedures, achieving unprecedented scalable preparation of NFAs in the lab at a 10-g scale notably within one day. The single-crystal structures of F11 reveals the 3D network packing. F11 and F13 display the lowest costs among reported NFAs, even comparable with the classical donor material, P3HT. By matching a medium-bandgap polymer donor, F13 delivers power conversion efficiencies of over 13%, which is an efficiency record for non-INCN acceptors. Benefiting from the intrinsically high stability, OSCs based on F11 and F13 show device stability superior to the typical ITIC- and Y6-based OSCs as evidenced by the tiny burn-in losses. The current work presents a first example for large-scale preparation of low-cost NFAs with good efficiency and high device stability, which is significant for OSC commercialization in near future.

Flow Pd(II)-Catalysced Carbonylative Cyclisation in the Total Synthesis of Jaspine B

This work describes the total synthesis of jaspine B involving the highly diastereoselective Pd(II)-catalysed carbonylative cyclisation in the preparation of crucial intermediates. New conditions for this transformation were developed and involved the pBQ/LiCl as a reoxidation system and Fe(CO)5 as an in situ source of stoichiometric amount of carbon monoxide (1.5 molar equivalent). In addition, we have demonstrated the use of a flow reactor adopting proposed conditions in the large-scale preparation of key lactones.

Fe-Based Single-Atom Nanozyme with Superior Peroxidase-Mimicking Activity for Enhanced Ultrasensitive Biosensing

Nanomaterials with intrinsic enzyme-mimicking characteristics, refered to as nanozymes, have become a hot research topic owing to their unique advantages of comparative low cost, high stability and large-scale preparation. Among them, Single-atom nanozymes (SAzymes), as novel nanozymes with abundant atomically dispersed active sites, have caused specific attention in the development of nanozymes for their remarkable catalytic activities, maximum atomic utilization and excellent selectivity, the homogeneous catalytic sites and clear catalytic mechanisms. Herein, a novel single-atom nanozyme based on Fe(III)-doped polydiaminopyridine nanofusiforms (Fe-PDAP SAzyme) was successfully proposed via facile oxidation polymerization strategy. With well-defined coordination structure and abundant Fe-Nx active sites similar to natural metalloproteases, the Fe-PDAP SAzyme exhibits superior peroxidase-like activity by efficiently decomposing H2O2 for hydroxyl radical (.OH) species formation. Based on their superior peroxidase-like activity, colorimetric biosensing of H2O2 and glucose in vitro was performed by using a typical 3,3,5,5-tetramethylbenzidine through a multienzyme biocatalytic cascade platform, exhibiting the superior specificity and sensitivity. This work not only provides a novel promising SAzyme-based biosensor but also paves an avenue for evaluating enzyme activity and broadens the application of other nanozyme-based biosensors in the fields of biomedical diagnosis.

Enantioselective aza-Michael Cyclization Reaction Catalyzed by Quinine-Derived Monoquaternary Ammonium Salts: an Effective Route to Synthesize Letermovir

A series of mono- or bis-quaternary ammonium salts derived from cinchonidine or quinine was synthesized and screened as potent phase-transfer catalysts for the reaction of aza-Michael cyclization, the key step in the synthesis of letermovir. During the reaction of aza-Michael cyclization, the screened monoquaternary ammonium salt quinine derivative Q1 transferred 7 to 8 with 91.9% yield and 58% ee. The application of Q1 was preferred, due to its enantioselectivity, the possibility of reuse, and the lower cost in large-scale preparation. Furthermore, the racemization condition of letermovir enantiomer was also explored for the possibility to develop the resolution/racemization process. With the optimal catalyst Q1 in hand, the synthesis of letermovir may be more convenient and economical in the future.