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An operationally simple, one-pot synthetic protocol for the formation of all-carbon, highly substituted five- and six-membered rings is described. In this two-step procedure, an asymmetric allylic alkylation (AAA) of Morita-Baylis-Hillman (MBH) carbonates with allylmalononitrile, catalyzed by a chiral tertiary amine, is followed by a ring-closing alkene metathesis (RCM) reaction. Products are obtained in high yields, and an excellent level of optical purity of some of the target compounds is achieved after just a single recrystallization. [ABSTRACT FROM AUTHOR]

Abstract: Organocatalytic alkynylation of nucleophilic fluorocarbons using hypervalent iodine compounds under cinchona-based catalysis, namely using O-allyl N-anthracenyl cinchona alkaloid derivative II, is described. The reaction gives the final fluoro-propargyl compounds in good to excellent yields (up to 91%) and with moderate to low enantioselectivity (up to 61% ee). The reaction represents the first example of the use of hypervalent iodine compounds for the construction of fluorinated compounds and opens access to the preparation of biologically attractive compounds such as 1,2,3-triazoles. [Copyright &y& Elsevier]

Abstract: This review describes the state of the art in the field of polyoxometalates containing noble metal atoms (ruthenium, rhodium, palladium, silver, osmium, iridium, platinum and gold). The structures of the various species are listed together with their applications (mainly in catalysis). [Copyright &y& Elsevier]

The quenching of the luminescence originating from the excited states 3P0 and 1D2 of Pr3+ and 5D3 and 5D4 of Tb3+ has been studied in oxide crystals containing closed shell transition metal ions, such as titanates, vanadates, niobates, and tantalates. It has been shown that the emission from these excited states can be quenched by an intervalence charge transfer mechanism. The temperature dependence of the emission intensities has allowed estimating indicative activation energies for the crossover to the intervalence charge transfer state. In the case of Tb3+, the quenching gives rise to relatively short decay times for the 5D4 state. [ABSTRACT FROM AUTHOR]

Disulfide conjugation invariably remains a key tool in research on nucleic acids. This versatile and cost-effective method plays a crucial role in structural studies of DNA and RNA as well as their interactions with other macromolecules in a variety of biological systems. In this article we review applications of disulfide-bridged conjugates of oligonucleotides with other (bio)molecules such as peptides, proteins etc. and present key findings obtained with their help. [ABSTRACT FROM AUTHOR]

This 2-part article reviews methods of oligonucleotides functionalization with thiol tethers and their consecutive use in conjugation with other (macro)molecules via a disulfide bridge. This relatively inexpensive, robust and reversible method of conjugation of DNAs, RNAs and their analogs holds a prominent position in a modern biochemistry toolbox and therefore there is a wealth of literature on the subject. In part I methods of thiol/disulfide groups introduction into oligonucleotide strands have been systematized and discussed. A digest of conjugation methods is presented as well. [ABSTRACT FROM AUTHOR]

An efficient asymmetric allylic alkylation of Morita-Baylis-Hillman adducts with allyl and homoallyl malononitrile is developed. [ABSTRACT FROM AUTHOR]

A new reaction based on synergistic catalysis, in which two catalytic cycles involving organometallic activation of an alkyl azaarene by AgOAc and Lewis base (DABCO) activation of a Morita-Baylis-Hillman carbonates, is developed. [ABSTRACT FROM AUTHOR]

The alkynylation of nucleophilic fluorocarbons (II) with hypervalent iodine compound (I) is developed using a cinchona alkaloid derivative as catalyst. [ABSTRACT FROM AUTHOR]

Sensitive and rapid point-of-care assays have been crucial in the global response to SARS-CoV-2. Loop-mediated isothermal amplification (LAMP) has emerged as an important diagnostic tool given its simplicity and minimal equipment requirements, although limitations exist regarding sensitivity and the methods used to detect reaction products. We describe the development of Vivid COVID-19 LAMP, which leverages a metallochromic detection system utilizing zinc ions and a zinc sensor, 5-Br-PAPS, to circumvent the limitations of classic detection systems dependent on pH indicators or magnesium chelators. We make important strides in improving RT-LAMP sensitivity by establishing principles for using LNA-modified LAMP primers, multiplexing, and conducting extensive optimizations of reaction parameters. To enable point-of-care testing, we introduce a rapid sample inactivation procedure without RNA extraction that is compatible with self-collected, non-invasive gargle samples. Our quadruplexed assay (targeting E, N, ORF1a, and RdRP) reliably detects 1 RNA copy/µl of sample (=8 copies/reaction) from extracted RNA and 2 RNA copies/µl of sample (=16 copies/reaction) directly from gargle samples, making it one of the most sensitive RT-LAMP tests and even comparable to RT-qPCR. Additionally, we demonstrate a self-contained, mobile version of our assay in a variety of high-throughput field testing scenarios on nearly 9,000 crude gargle samples. Vivid COVID-19 LAMP can be an important asset for the endemic phase of COVID-19 as well as preparing for future pandemics. Vivid COVID-19 LAMP is an ultrasensitive zinc ion and zinc sensor based colorimetric detection system, reliably detecting viral RNA from self-collected, non-invasive gargle samples for rapid point-of-care testing. [ABSTRACT FROM AUTHOR]

Summary: Sensitive and accurate RT‐qPCR tests are the primary diagnostic tools to identify SARS‐CoV‐2‐infected patients. While many SARS‐CoV‐2 RT‐qPCR tests are available, there are significant differences in test sensitivity, workflow (e.g. hands‐on‐time), gene targets and other functionalities that users must consider. Several publicly available protocols shared by reference labs and public health authorities provide useful tools for SARS‐CoV‐2 diagnosis, but many have shortcomings related to sensitivity and laborious workflows. Here, we describe a series of SARS‐CoV‐2 RT‐qPCR tests that are originally based on the protocol targeting regions of the RNA‐dependent RNA polymerase (RdRp) and envelope (E) coding genes developed by the Charité Berlin. We redesigned the primers/probes, utilized locked nucleic acid nucleotides, incorporated dual probe technology and conducted extensive optimizations of reaction conditions to enhance the sensitivity and specificity of these tests. By incorporating an RNase P internal control and developing multiplexed assays for distinguishing SARS‐CoV‐2 and influenza A and B, we streamlined the workflow to provide quicker results and reduced consumable costs. Some of these tests use modified enzymes enabling the formulation of a room temperature‐stable master mix and lyophilized positive control, thus increasing the functionality of the test and eliminating cold chain shipping and storage. Moreover, a rapid, RNA extraction‐free version enables high sensitivity detection of SARS‐CoV‐2 in about an hour using minimally invasive, self‐collected gargle samples. These RT‐qPCR assays can easily be implemented in any diagnostic laboratory and can provide a powerful tool to detect SARS‐CoV‐2 and the most common seasonal influenzas during the vaccination phase of the pandemic. [ABSTRACT FROM AUTHOR]

The article focuses on the catalytic oxidation of light alkanes (C1-C4) by heteropoly compounds (HPC). Topics discussed include structural mobility use of HPC in oxidative catalysis, mechanisms for methane selective oxidation to oxygenate involving methanol and formaldehyde, and selective oxidation of iso-butane to methacrolein and methacrylic acid.

An expedited method has been developed for the diastereoselective synthesis of highly functionalized alkyl-azaarene systems with good yields and high diastereoselectivities (>15: 1 dr). The methodology includes a synergistic catalysis event involving organometallic (10 mol% AgOAc) activation of an alkyl azaarene and Lewis base (10 mol% DABCO) activation of a Morita-Baylis-Hillman carbonate. The structure and relative configuration of a representative product were confirmed by X-ray analysis. [ABSTRACT FROM AUTHOR]