Construction of Spiro[pyrrolidine-azlactone] via [2 + 3] Cycloaddition of Alkylidene Azlactone with Trifluoromethylated Imine.

A Ag-catalyzed [2 + 3] cycloaddition of alkylidene azlactones with trifluoromethylated imines has been documented, providing spiro[pyrrolidine-azlactones] bearing four adjacent stereogenic centers with good yields and excellent diastereoselectivities. Catalytic asymmetric cycloaddition has also been developed with good yields and excellent enantioselectivities. Further gram-scale preparation and synthetic transformation to pyrrolidine derivative showed the good practicality and applicability of this reaction.

Establishment and application of highly efficient regeneration, genetic transformation and genome editing system for cucurbitacins biosynthesis in Hemsleya chinensis.

Background: Hemsleya Chinensis is a perennial plant in the Cucurbitaceae family containing antibacterial and anti-inflammatory compounds. The lack of genetic transformation systems makes it difficult to verify the functions of genes controlling important traits and conduct molecular breeding in H. chinensis.

Decoding the Root Lignification Mechanism of Angelica sinensis through Genome-wide Methylation Analysis.

Angelica sinensis is a traditional Chinese herbal medicine with significant economic and medicinal value. However, early bolting and flowering can occur during the second year of the vegetative growth period, rendering the roots unviable for medicinal use and resulting in substantial economic losses. Consequently, the growing interest in studying the molecular mechanisms underlying early bolting or increased root lignification in A.

Elucidation of AsANS controlling pigment biosynthesis in Angelica sinensis through hormonal and transcriptomic analysis.

Angelica sinensis, a traditional Chinese medicinal plant, has been primarily reported due to its nutritional value. Pigmentation in this plant is an important appearance trait that directly affects its commercial value. To understand the mechanism controlling purpleness in A.

Synthesis of Pyrimido[1,2-]indolediones and Pyrimidinediones via [4+2] Annulation of 2-Azirine-2-carbaldehydes.

NHC-catalyzed [4+2] annulation of 2-azirine-2-carbaldehydes with ketimines and isocyanates has been developed, providing straightforward synthetic protocols for constructing structurally intriguing pyrimido[1,2-]indolediones and pyrimidinediones under mild conditions with excellent yields. This protocol can be used to synthesize the core skeleton of pharmaceutically important drugs and pyrimido[1,2-]indoledione-containing natural products, making it potentially valuable for creating biologically active derivatives.

Catalytic Asymmetric Synthesis of 3,4'-Piperidinoyl Spirooxindoles via [3 + 3] Annulation of 3-Aminobenzofurans and Isatin-Derived Enals.

A chiral NHC-catalyzed [3 + 3] cycloaddition reaction of 3-aminobenzofurans with isatin-derived enals has been documented, furnishing 3,4'-piperidinoyl spirooxindoles bearing a quaternary stereocenter with good yields and excellent enantioselectivities. Further gram-scale preparation and synthetic transformation of the cycloadducts to δ-amino acid derivative demonstrated good practicality and applicability of this reaction.

Control of Aluminum and Titanium Contents in the Electroslag Remelting of ATI 718Plus Alloy.

The burning loss of Al and Ti elements in superalloys during electroslag remelting has become a prevalent issue. And the existing slag system is not suitable for smelting the ATI 718Plus alloy. Therefore, it is imperative to develop a new slag system for smelting the ATI 718Plus alloy.

Synthesis of Pyridazino[4,5-b]indoles by [3+3] Annulation of 2-Alkenylindoles and Hydrazonyl Chlorides.

A novel [3+3] annulation reaction of 2-alkenylindoles with hydrazonyl chlorides in the presence of base for the formation of pyridazino[4,5-b]indoles was developed. This approach provided a convenient and efficient way to synthesize a series of functionalized pyridazino[4,5-b]indoles derivatives. The method exhibited a broad substrate scope and provided the corresponding pyridazino[4,5-b]indoles products with excellent yields.

Iron-Catalyzed Cleavage Reaction of Keto Acids with Aliphatic Aldehydes for the Synthesis of Ketones and Ketone Esters.

The radical-radical coupling reaction is an important synthetic strategy. In this study, the iron-catalyzed radical-radical cross-coupling reaction based on the decarboxylation of keto acids and decarbonylation of aliphatic aldehydes to obtain valuable aryl ketones is reported for the first time. Remarkably, when tertiary aldehydes were used as carbonyl sources, ketone esters were selectively obtained instead of ketones.

Metal- and solvent-free synthesis of amides using substitute formamides as an amino source under mild conditions.

This study described an efficient and practical approach for amide synthesis. The reaction was conducted under metal- and solvent-free conditions at a mild temperature (40 °C) in air, and readily available formamides were used as an amino source. This reaction can be easily upgraded to the gram level with an excellent yield.

MoS-Catalyzed transamidation reaction.

The MoS-catalyzed transamidation reaction with high yields using N,N-dimethylformamide and other amides as carbonyl sources is developed here. The protocol is simple, does not require any additive such as acid, base, ligand, etc., and encompasses a broad substrate scope for primary, secondary and heterocyclic amines.

Tandem Oxidative Ring-Opening/Cyclization Reaction in Seconds in Open Atmosphere for the Synthesis of 1-Tetralones in Water-Acetonitrile.

A mild and practical tandem oxidative ring-opening/cyclization reaction mediated by Ce for the synthesis of 1-tetralones is presented. This rapid transformation was completed within 30 s and conducted in an open reactor at 0 °C in a water-acetonitrile mixture. Various cyclobutanol derivatives are transformed into desired products in good to high yields, and this reaction can be easily scaled up to the gram scale.

Palladium-Catalyzed Direct α-Ketoesterification of 8-Methylquinoline Derivatives with α-Ketoacids via Dehydrogenation Coupling Reaction.

A direct, regiospecific, and efficient palladium-catalyzed α-ketoesterification of 8-methylquinoline derivatives to generate α-ketoesters has been discovered. This reaction is conducted at a mild temperature, free of peroxide, and compatible with air, and various α-ketoesters were achieved with good yields. Importantly, this reaction can be easily amplified to gram level using only 1 mol % of the palladium catalyst, indicating that there is the potential for further reduction of the amount of catalyst loading required for large-scale production.