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An effective Pd(0)-catalyzed hydrocarboxylation of 1,2-disubstituted enimides with formic acid and HCOOPh is described. A variety of β 2 -amino acid derivatives are obtained in good yield with high regioselectivity without using external toxic CO gas.

In this report we present the first successful homogenous asymmetric hydrogenation of heavily hindered and minimally functionalized tetrasubstituted cyclic olefins bearing three aromatic substituents, which represent key precursors of lasofoxifene tartrate. The success of our hydrogenation method is based on the surprising discovery that Br?nsted acids or Lewis acids can significantly enhance the reactivity of these substrates towards hydrogenation with Ir–P^N complexes. Iterative screens of Ir–P^N catalysts, additives and reaction conditions led to high to full conversions with high ee. The obtained hydrogenation products are easily converted to optically pure selective estrogen receptor modulator lasofoxifene tartrate in significantly higher overall yield compared to previously reported methods.

The Pd(TFA) 2 -catalyzed denitrogenative addition proceeded with selective C–N bond cleavage of arylhydrazines with nitriles in the presence of DABCO and HFBA under air at room temperature. Aryl ketones could be easily synthesized via the hydrolysis of the ketimine moiety generated in situ without the need for additional water.

An efficient approach to generate aryl gold carbenes has been developed. The reaction was proposed to proceed through an intramolecular sequential activation of a 1,6-diyne and aromatization to produce the desired aryl carbene, which was featured with a safe and practical process, mild reaction conditions and high atom efficiency.

Neplanocin A analogs have attracted attention in the fields of biological and medicinal chemistry due to their potent and broad-spectrum antiviral and antitumor activities. To further explore their potential as therapeutic agents, an alternative and efficient synthesis of fluoro-neplanocin A analogs has been developed by employing stereoselective electrophilic fluorination and palladium-catalyzed dehydrosilylation as key steps. With respect to previous syntheses, the present synthetic methodology provides easy access to key intermediates that could contribute to expanding further the structure–activity relationship studies of neplanocin A analogs.

Chemical investigation of a soil actinomycete strain Streptomyces gamaensis NEAU-Gz11 led to the isolation of three alkaloids 1–3 with antiviral activity. Their structures were determined by extensive spectroscopic and X-ray crystallographic analyses. Compound 1 possesses a new and unique spiro-β-triazinedione-γ-hydantoin skeleton. The racemic feature and the chemical conversion experiments led us to propose a biosynthetic pathway for 1 . Compound 1 (100 mg L ?1 ) showed a strong anti-TMV (tobacco mosaic virus, TMV) activity on the host plants of tomatoes and peppers with inhibition rates of 72.34% and 62.09%, respectively.

An acid/DEAD system for efficient oxidative cleavage of S–S and Se–Se bonds to generate chalcogenium ions has been developed. These ions could be captured by nucleophile-tethered alkenes and nucleophilic aryl reagents such as arylboronic acids and arenes to afford diverse chalcogenides. Mechanistic studies revealed that an N -sulfenylhydrazine intermediate was involved in the transformations.

A convenient and practical pathway to versatile silylated amides and anilides is described via efficient and selective ruthenium( II ) catalyzed ortho C–H silylation. Both amides and anilides were successfully silylated with good functional group tolerance and high regioselectivity. Different alkenes as the hydrogen acceptors played a crucial role in these two catalytic systems. Unexpectedly, two pathways for RuHCl(CO)(PPh 3 ) 2 /KOAc catalyzed C–H silylation involving a 5-membered ruthenacycle with arylamides and a 6-membered ruthenacycle with arylanilides, take place depending on the nature of the alkene as the hydrogen trapper.

Twelve undescribed bisindole alkaloids, tabernaemontines A–L, were simultaneously isolated from the leaves of Tabernaemontana bovina and their structures were elucidated by spectroscopic methods. All alkaloids consist of two Aspidosperma -type units with various intramolecular linkages. Particularly, tabernaemontines A–D were assembled through C-3/14′ with a large angle strain, whilst tabernaemontines E–K adopted a preferential conformation. Tabernaemontine L was assembled via a C-14/10′ connection. Tabernaemontines F, K and L showed good inhibition of microglial activation. As a representative of Aspidosperma -type dimers, the P38 MAPK activation inhibition properties of tabernaemontine F were tested. The promising results revealed this compound as a potential candidate for the treatment of chronic neurodegenerative diseases.

In this work, the synthesis and modulation as well as the mechanisms of a series of 3-aminomaleimide fluorophores based on the air oxidation of 3-aminosuccinimides are reported through combined experimental and computational studies. The central observations include the following: (1) the evident fluorescence observed in the Michael addition reaction of amine to maleimide was attributed to the formation of 3-aminomaleimide fluorophores via the air oxidation process, (2) the chemical conversion from aminosuccinimide to aminomaleimide is thermodynamically favourable and a series of primary and secondary amines are compatible with this reaction, and (3) the steric and electronic effects exerted by amino substituted groups can effectively inhibit twisted intramolecular charge transfer (TICT) and markedly improve the quantum yields of 3-aminomaleimide fluorophores. As a proof-of-concept, the 3-aminomaleimides manifested themselves as efficient fluorophores that can be readily applied in solid emission for optical waveguides and emissive oligomers for bioimaging. Our findings establish a new frontier on the innovative synthesis and accurate modulation of simple luminescent structures for versatile, high-performance functional materials.