A P catalyst for stereogenic P(III): Phosphodiesters, the key linkage in DNA, RNA, and bioactive oligonucleotide and cyclic nucleotides, are typically synthesized from phosphoramidite precursors. Phosphorothioate linkages, which are more stable, can also be produced this way but have the complication of chirality at the P center, which is synthetically problematic, especially for multiple linkages. Featherston et al. found that two different chiral phosphoric acid catalysts provide stereodivergent synthesis of a stereogenic phosphite intermediate that can be oxidatively modified to the desired stereopure nucleotide derivative. They used this approach in the synthesis of a phosphorothioate derivative of the cyclic dinucleotide 2′,3′-cyclic guanosine monophosphate adenosine monophosphate, which is an important human immune signaling molecule. Science , this issue p. 702

Atropisomeric compounds have been discovered in pharmaceuticals and materials science, and their enantioselective syntheses have gained tremendous attention. Among strategies for catalytic atroposelective synthesis, desymmetrization provides robust and straightforward approaches to axially chiral biaryls. Due to the relative ease of substrate design compared to other atroposelective strategies, desymmetrization has emerged as a pivotal stage for converting fascinating chemistry into its atroposelective counterpart, despite challenges such as the formation of achiral products by subsequent catalytic reactions and the long distance between the reaction site and the stereogenic axis. This review offers a comprehensive overview of recent advancements in atroposelective desymmetrization using chiral organo‐ and metal catalysts, addressing challenges and solutions, and aims to provide insights into future developments in this field.

Chemically modified proteins have diverse applications; however, conventional chemo‐selective methods often yield heterogeneously labeled products. To address this limitation, site‐specific protein labeling holds significant potential, driving extensive research in this area. Nevertheless, site‐specific modification of native proteins remains challenging owing to the complexity of their functional groups. Therefore, a method for site‐selective labeling of intact proteins is aimed to design. In this study, a novel approach to traceless affinity‐directed intact protein labeling is established, which leverages small binding proteins and genetic code expansion technology. By applying this method, a site‐specific antibody labeling with a drug, which leads to the production of highly effective antibody‐drug conjugates specifically targeting breast cancer cell lines is achieved. This approach enables traceless conjugation of intact target proteins, which is a critical advantage in pharmaceutical applications. Furthermore, small helical binding proteins can be easily engineered for various target proteins, thereby expanding their potential applications in diverse fields. This innovative approach represents a significant advancement in site‐specific modification of native proteins, including antibodies. It also bears immense potential for facilitating the development of therapeutic agents for various diseases.

As the complexity of organic molecules utilized by mankind increases, the phenomenon of atropisomerism is more frequently encountered. While a variety of well-established methods enable the control of a stereogenic center, a catalytic method for controlling a stereogenic axis in one substrate is typically unavailable for controlling axial chirality in other substrates with a similar structure. Herein, we report o-amidobiaryl as a flexible platform for chiral phosphoric acid-catalyzed atroposelective dynamic kinetic resolution. To demonstrate our strategy, three distinct types of arylindoles were utilized and reacted intermolecularly with ketomalonate in the presence of chiral phosphoric acid. An investigation of 46 substrates having an aromatic ring in different positions yields the desired products with excellent enantioselectivities. Computational investigation into the origin of enantioselectivity highlights the importance of the NH group. Given the biological significance of indoles, antiproliferative effects have been investigated; our scaffold exhibits good efficacy in this regard.