Recently, reversible click reactions have found numerous applications in chemical biology, supramolecular chemistry, and biomedical applications. Boronic acid (BA)-mediated
cis
-diol conjugation is ...one of the best-studied reactions among them. An excellent understanding of the chemical properties and biocompatibility of BA-based compounds has inspired the exploration of novel chemistries using boron to fuel emergent sciences. This topical review focuses on the recent progress of iminoboronate and salicylhydroxamic-boronate constituted reversible click chemistries in the past decade. We highlight the mechanism of reversible kinetics and its applications in chemical biology, medicinal chemistry, biomedical devices, and material chemistry. This article also emphasizes the fundamental reactivity of these two conjugate chemistries with assorted nucleophiles at variable pHs, which is of utmost importance to any stimuli-responsive biological and material chemistry explorations.
Fundamental progress, current developments, and rapidly growing applications of iminoboronate and salicylhydroxamic-boronate conjugate esters are deliberated.
Statistical analysis techniques such as principal component analysis (PCA) and discriminant analysis (DA) have become an integral part of data analysis for differential sensing. These multivariate ...statistical tools, while extremely versatile and useful, are sometimes used as "black boxes". Our aim in this paper is to improve the general understanding of how PCA and DA process and display differential sensing data, which should lead to the ability to better interpret the final results. With various sets of model data, we explore several topics, such as how to choose an appropriate number of hosts for an array, selectivity compared to cross-reactivity, when to add hosts, how to obtain the best visually representative plot of a data set, and when arrays are not necessary. We also include items at the end of the paper as general recommendations which readers can follow when using PCA or DA in a practical application. Through this paper we hope to present these statistical analysis methods in a manner such that chemists gain further insight into approaches that optimize the discriminatory power of their arrays.
By mimicking the mammalian senses of taste and smell, artificial arrays of cross-reactive receptors have found use in a variety of sensing applications. Pattern recognition algorithms allow these ...arrays to be used for discriminating analytes and even for predicting the identity of unknown analytes. Furthermore, in selecting a signaling method for these assays, the choice of optical detection is particularly desirable due to its high sensitivity and the associated convenient instrumentation. This tutorial review provides a brief introduction to array sensing using optical detection and chemometrics. While differential sensing approaches have been used for a number of applications, this review focuses on progress towards the detection of chemical and biological hazards.
High-throughput screening (HTS) methods are becoming increasingly essential in discovering chiral catalysts or auxiliaries for asymmetric transformations due to the advent of parallel synthesis and ...combinatorial chemistry. Both parallel synthesis and combinatorial chemistry can lead to the exploration of a range of structural candidates and reaction conditions as a means to obtain the highest enantiomeric excess (ee) of a desired transformation. One current bottleneck in these approaches to asymmetric reactions is the determination of ee, which has led researchers to explore a wide range of HTS techniques. To be truly high-throughput, it has been proposed that a technique that can analyse a thousand or more samples per day is needed. Many of the current approaches to this goal are based on optical methods because they allow for a rapid determination of ee due to quick data collection and their parallel analysis capabilities. In this critical review these techniques are reviewed with a discussion of their respective advantages and drawbacks, and with a contrast to chromatographic methods (180 references).
Chemical warfare agents (CWAs) are among the most prominent threats to the human population, our peace, and social stability. Therefore, their detection and quantification are of utmost importance to ...ensure the security and protection of mankind. In recent years, significant developments have been made in supramolecular chemistry, analytical chemistry, and molecular sensors, which have improved our capability to detect CWAs. Fluorescent and colorimetric chemosensors are attractive tools that allow the selective, sensitive, cheap, portable, and real-time analysis of the potential presence of CWAs, where suitable combinations of selective recognition and transduction can be integrated. In this review, we provide a detailed discussion on recently reported molecular sensors with a specific focus on the sensing of each class of CWAs such as nerve agents, blister agents, blood agents, and other toxicants. We will also discuss the current technology used by military forces, and these discussions will include the type of instrumentation and established protocols. Finally, we will conclude this review with our outlook on the limitations and challenges in the area and summarize the potential of promising avenues for this field.
A new auto‐inductive protocol employs a Meldrum's‐acid‐based conjugate acceptor (1) as a latent source of thiol for signal amplification, as well as optical detection of thiols. The auto‐induction is ...initiated by a thiol‐disulfide exchange that leads to the generation of β‐mercaptoethanol, which in turn decouples the conjugate acceptor to release more thiols, resulting in a self‐propagating cycle that continues until all the conjugate acceptor is consumed. Using 1 in a two‐step integrated protocol yields a rapid, sensitive, and precise diagnostic assay for the ultratrace quantitation of a thiophosphate nerve agent surrogate.
Thiol detection: Combining thiol‐disulfide exchange with decoupling of a conjugate acceptor (1), a new thiol auto‐inductive cascade was developed for signal amplification, as well as colorimetric and fluorometric detection of thiols. Using 1 in a two‐step protocol yields a rapid assay for the ultratrace quantitation of a thiophosphate nerve agent surrogate at ppb levels.
Dynamic assembly of macromolecules in biological systems is one of the fundamental processes that facilitates life. Although such assembly most commonly uses noncovalent interactions, a set of ...dynamic reactions involving reversible covalent bonding is actively being exploited for the design of functional materials, bottom‐up assembly, and molecular machines. This Minireview highlights recent implementations and advancements in the area of tunable orthogonal reversible covalent (TORC) bonds for these purposes, and provides an outlook for their expansion, including the development of synthetically encoded polynucleotide mimics.
TORC about: The utilization of tunable orthogonal reversible covalent (TORC) bonds is highlighted in this Minireview. The focus lies in the variety of different applications that are possible, including controlling molecular assembly, operating complex molecular machines, and designing dynamic, self‐healable polymer networks.
This Perspective highlights the advances of optical methods for asymmetric reaction discovery. Optical analysis allows for the determination of absolute configuration, enantiomeric excess and ...reaction yield that is amenable to high-throughput experimentation. Thus, the synthetic organic community is encouraged to incorporate the methods discussed to expedite the development of high-yielding, enantioselective transformations.
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