Israel Journal of Chemistry最新文献

Herbal medicines (HMs) are gaining increasing popularity and recognition worldwide due to their eco-friendliness and efficacy. With their multi-compounds, multi-targets, and multi-pathways characteristics, HMs have been used in treatment of various diseases. However, the clinical applications of preparations containing HMs have been limited due to their inherent physicochemical properties, including low water solubility, poor stability, and unsatisfactory bioavailability of bioactive compounds. Supramolecular macrocyclic hosts, like cyclodextrins, calixarenes, cucurbiturils, and pillararenes, are important objects of researches in supramolecular chemistry. These hosts have been utilized to encapsulate the ingredients, improve the solubility of poorly water-soluble components, enhance the stability of the tested compounds, increase the bioavailability of bioactive compounds, and ensure the safety of HMs. Herein, we provide a brief introduction to the theories of supramolecular chemistry and summarize the extensive applications of supramolecular macrocyclic hosts in the field of HMs. These applications encompass the screening of bioactive compounds in HMs and the enhancement of druggability for HMs. We hope this review can provide a strategy for dealing with the challenges of HMs, thereby enabling their better applications and development.

A promising, but not yet practiced, approach to the treatment of neurotoxic organophosphate poisoning is the administration of a scavenger that rapidly deactivates the nerve agent before it can exert its toxic effects. The detoxification rates required for successful use of this therapy can currently only be achieved with enzymes, but synthetic scavengers, whose mode of action is based on key concepts of supramolecular chemistry, are an attractive alternative. Considerable progress has recently been made in the development of such scavengers, and compounds from several receptor classes are now available that not only bind nerve agents but also degrade them at promising rates. This review provides an overview of the field and highlights recent developments.

The intricate network of cell functions relies on gene expression programs, where the whole RNA life cycle from DNA to protein is subjected to extensive transcriptional and post-transcriptional gene regulation events. Established bulk RNA sequencing methods provide an averaged, transcriptome-wide quantification of the RNA life cycle, including transcription, processing, translation, transport, and degradation through RNA-protein interactions. Furthermore, numerous studies using bulk epitranscriptomic profiling unveiled that dynamic RNA modifications (e. g., N⁶-Methyladenosine), add another layer of gene regulations. However, many regulatory events are cell-type specific, subcellularly localized, and subjected to cell-cell communications within the native tissue environment. Thanks to the advances in single-cell sequencing, spatial sequencing, and highly multiplexed imaging methods, we can routinely measure single-cell and spatial transcriptomics. Yet more comprehensive methods to profile every step of the RNA life cycle with single-cell and spatial information are still lacking. In this review, we will summarize and compare early explorations in developing state-of-the-art methods for spatially and single-cell resolved mapping of RNA kinetics, translation, RNA-protein interactions, and epitranscriptomics. It is promising that these new techniques will greatly facilitate our understanding of the RNA-centered regulation landscapes in different cell types and how the post-transcriptional regulations are interconnected within cellular and tissue architecture.

Cellular DNA and RNA are decorated with diverse chemical modifications, which add new layers to gene regulation and play crucial roles across development and disease progression. Interest in understanding the functions of DNA and RNA modifications, as well as the related molecular mechanisms, has been growing, driving progress in developing chemical and biochemical tools to detect specific modifications. New technologies are important not only for uncovering biological functions, but also for driving conceptual revolutions. In this review, we highlighted our recent advances in developing new chemical tools to detect DNA and RNA modifications in a direct, quantitative, and base-resolution manner. These includes a novel borane reduction chemistry for DNA methylation sequencing; new cytosine modificaiton oxdation chemistry for enhanced DNA hydroxymethylation sequencing; and a novel bromoacrylamide cyclization chemistry for RNA pseudouridylation sequencing. We present a mechanistic overview of these tools and their applications in epigenetic and epitranscriptomic research.

Shape-persistent organic cages are an intriguing class of molecular porous materials. Through hierarchical molecular design, size and shape of the intrinsic molecular voids are controlled by dynamic covalent chemistry, while pore structure and topology are governed by noncovalent alignment in the solid state. However, the predictable and reliable crystallization of organic cages is still challenging since long-range superstructures are solely based on weak and rather unidirectional supramolecular interactions. In this tutorial review, we provide a general classification of porous solid-state materials and discuss specific design principles regarding the dynamic covalent reactions, the small-molecule building blocks and solid-state engineering. Furthermore, we introduce the most important analytical techniques for porous materials with a special focus on organic cages.