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Cephalotaxus diterpenoids are attractive natural products with intriguing molecular frameworks and promising biological features. As a structurally unusual member, (−)‐cephalotanin B possesses an extraordinarily congested heptacyclic skeleton, three lactone units, and nine consecutive stereocenters. Herein, we report an enantioselective total synthesis of (−)‐cephalotanin B based on a divergent asymmetric Michael addition reaction, a novel Pauson–Khand/deacyloxylation process discovered in the development of a second‐generation stereoselective Pauson–Khand reaction protocol, and an epoxide‐opening/elimination/dual‐lactonization cascade to construct the challenging propeller‐shaped A–B–C ring system as key transformations. [ABSTRACT FROM AUTHOR]

The growth of the global population poses a huge challenge to food security. The continuous application of crop protection products has many negative effects including increased pesticide resistance, accumulation of residues, and ecological damage. The challenge for the future is to develop agrochemicals with that are effective, with a high degree of selectivity, environmental friendliness, a low use rate, and cost‐effectiveness. Cutting‐edge developments in natural product chemistry, asymmetric synthesis, and rational drug design, as well as an increasing knowledge of the mechanisms that induce plant immunity, have provided potential solutions. In this review, we discuss the comprehensive use of emerging technologies that will help to tackle these current challenges and issues, highlighting the discovery of novel crop production products and their beneficial properties. [ABSTRACT FROM AUTHOR]

ω-transaminases are able to catalyze the reversible transfer of amino groups between diverse amino compounds (such as amino acids, alkyl amines, aromatic amines) and carbonyl compounds (such as aldehydes, ketones, ketoacids). ω-transaminases exhibit great application prospects in the field of chiral amine biosynthesis because of their desirable properties, such as wide range of substrates, high stereoselectivity, and mild catalytic conditions. It is therefore important for China to develop efficient, specific, and environment-friendly chiral amine production technologies with independent intellectual property rights, which is of great significance for the development of pharmaceutical, pesticide, and material industries. This review systematically summarizes the Chinese patents regarding ω-transaminase filed by Chinese institutions in the recent decade. The development of ω-transaminase resource, enzymatic property improvement by protein engineering, application in chiral amine synthesis, and development of production technologies are elaborated. This review will shed light on further basic and application studies of ω-transaminase.

The asymmetric unit of the title compound, C18H17FN2O2S, contains two independent mol­ecules related by a pseudo-inversion centre. The mol­ecular packing is stabilized by C—H⋯O and C—H⋯π inter­actions. [ABSTRACT FROM AUTHOR]