The first organocatalytic Michael–cyclization cascade reaction between isothiocyanato oxindoles and unsaturated pyrazolones has been developed. multicyclic spiro[oxindole/thiobutyrolactam/pyrazolone] core structures containing three contiguous stereogenic centers, including two spiro quaternary were prepared with excellent diastereo- (up to >20 : 1) enantioselectivities 99% ee).

The first example of a highly enantioselective vinylogous Michael-type reaction β,β-disubstituted nitroalkenes is disclosed. A series biologically important chiral oxindoles, featuring trifluoromethylated all-carbon quaternary center, were obtained in good yields with excellent enantioselectivities (up to >99% ee).

The glycosylative modification of peptides could improve the pharmacological properties peptide drugs and deliver them efficiently to target sites. Compared with O-/N-glycosides, C-glycosides exhibit more metabolic stability. We here disclose first example visible-light-promoted Cu-catalyzed stereoselective C-glycosylation. mild reaction conditions are compatible various carbohydrate substrates, as demonstrated a series monosaccharides disaccharide, amenable synthesis wide variety...

The first organocatalytic double Michael cascade reaction between unsaturated ketones and pyrazolones has been developed which provides spiropyrazolone core structures containing two interval or three consecutive stereogenic centers with excellent diastereo- (>20 : 1) enantioselectivities (up to 99% ee). Moreover, a pair of enantiomers 5 5′ can be achieved via different catalysts.

The first direct thiocyanation of ketene dithioacetals has been accomplished in the presence <italic>N</italic>-chlorosuccinimide (NCS) and NH₄SCN under transition-metal-free conditions. Terminal alkenes hydrazine were identified to be qualified candidates for process as well.

Alkylnitriles play important roles in many fields because of their unique electronic properties and structural characteristics. Incorporating cyanoalkyl with characteristic spectroscopy reactivity into amino acids peptides is special interest for potential imaging therapeutic purposes. Here, we report a copper-catalyzed asymmetric cyanoalkylation C(sp3)-H. In the reactions, glycine derivatives can effectively couple various cycloalkanone oxime esters high enantioselectivities, reaction be...

C–H bond phosphorylation of ketene dithioacetals was achieved under transition-metal-free or AgNO3 mediated conditions. Synthetic transformations the coupling product provided promising methods for construction highly functionalized phosphorylated N-heterocycles and tetrasubstituted alkenes.

Abstract Carboxylic acids are common moieties in medicines. They can be converted to phthalidyl esters as prodrugs. Unfortunately, now mostly prepared racemic forms. This is not desirable because the two enantiomers of likely have different pharmacological effects. Here we address synthetic challenges enantioselective modification carboxylic via asymmetric acetalizations. The key reaction step involves addition a acid catalyst-bound intermediate. enantioselectively constructs chiral acetal...

A catalytic asymmetric method for the synthesis of 2-CF3 chromanes has been described. Generally, squaramide-catalyzed cascade reaction 2-hydroxychalcones with β-CF3-nitroalkenes gave CF3-containing heterocyclic compounds bearing three contiguous stereogenic centers in excellent yields, diastereoselectivities, and enantioselectivities.

Disclosed herein is a dehydrosilylative difluoroamidation of α-Csp3–H tetrahydroisoquinolines with α,α-difluoro-α-TMS-acetamides. The process, which occurs at ambient temperature in the absence any transition metals, provides direct access to broad range α,α-difluoroacetamide-substituted tertiary amine derivatives high yields. Moreover, method was successfully applied Csp3–H-directed difluorophosphorylation and difluorocarboxylation under same conditions.

Abstract This study investigates the behavioral patterns of children during emergency evacuations through a dual approach comprising controlled experimental within classroom and computational modeling via cellular automaton (CA) model. Observations from experiments reveal several characteristic behaviors among children, including preferences for destinations, impact obstacles on their movement, as well exit utilization, running pushing evacuation process. Drawing upon these empirical...

A AgOAc catalyzed difunctionalization of activated alkenes through a difluoroamidic radical addition to afford difluoroamidated 3,3-disubstituted oxindoles has been developed. Various functional groups were well tolerated. Moreover, the product could be efficiently derived corresponding difluorofunctionalized alcohol, ketone, and ester in high yields. The mechanistic studies revealed that pathway was involved transformation.

A class of o-(trimethylsilyl)aryl fluorosulfates was synthesized by a concise method and successfully used as aryne precursors for the first time. Different trapping agents such azides, furans, acyl acetoacetates could react with under mild conditions good to excellent yields.

Abstract Rhubarb is the collective name for various perennial plants from genus Rheum L. and Polygonaceae family. They are one of most ancient, commonly used, important herbs in traditional Chinese medicine. a major source anthraquinones, but how they synthesized remains largely unknown. Here, we generate genome sequence assembly medicinal rhubarb R. tanguticum at chromosome level, with 2.76 Gb assembled into 11 chromosomes. The shaped by two recent whole-genome duplication events bursts...

The first example of decarboxylative difluoroacetamidation α,β-unsaturated carboxylic acids by using difluoromethyl-substituted carbonyl compounds was disclosed. procedure, which mediated low-cost and benign CuSO4, furnished a broad range difluorinated alkenes in remarkable yields with only the E configuration most cases. Moreover, product could be smoothly transformed to corresponding difluorofunctionalized ester alcohol high yields.

Organic compounds with deuterated allyl groups are very attractive for drug entities to enhance pharmacokinetic properties, since allylic C–H bonds prone metabolic oxidation and the versions can be less such metabolism. However, direct deuteration at moieties is still a challenge. Few examples have been reported by transition-metal catalysis no reports documented in an organocatalytic fashion. Herein, carbene-catalyzed of enal C(sp3) C(sp2) centers disclosed. Addition carbene catalyst...

With the availability of well-assembled genomes a growing number organisms, identifying bioinformatic basis whole genome duplication (WGD) is field genomics. The most extant software for detecting footprints WGDs has been restricted to genome. However, massive poor quality and more accessible transcriptomes have largely ignored, in theoretically they are also likely contribute detect WGD using dS based method. Here, resolve these problems, we designed universal simple technical tool...

A highly efficient catalyst system assembled from enantiomerically pure diaminocyclohexane and Ni(OAc)2 is, for the first time, used to catalyze cascade Michael–Henry reaction of various diones substituted nitroalkenes. series polyfunctionalized bicyclo[3.2.1]octane derivatives containing four stereogenic centers are prepared with excellent enantioselectivities (up >99% ee) diastereoselectivities 50 : 1 dr) high yields. In addition, via this chiral diamine-Ni(OAc)2 system, base-induced...

An N-heterocyclic carbene-catalyzed direct oxidative coupling of enals and di(hetero)arylmethanes allows for quick access to optical pure benzimidazole-fused lactams.

Abstract We present a highly efficient strategy for obtaining series of chiral 2,4‐disubstituted thiazolone derivatives with excellent diastereo‐ and enantioselectivities through the creation carbon‐ nitrogen‐substituted quaternary carbon stereocenters. With tertiary amine‐thiourea catalyst developed by our group, reactions could be performed smoothly at 1 mol‐% loadings without any additive. Preliminary biological evaluation demonstrated that these analogues inhibit cell proliferation in...

A new, efficient and green protocol for the nano‐Cu 2 O‐catalyzed homo‐coupling reaction of terminal alkynes has been developed, using water/ionic liquid as an environmentally friendly solvent. Moreover, system also allows synthesis unsymmetric 1,3‐diynes by cross‐coupling two different alkynes. It is noteworthy that methodology a good supplement to copper catalyst Glaser‐type reaction. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Abstract The glycosylative modification of peptides could improve the pharmacological properties peptide drugs and deliver them efficiently to target sites. Compared with O ‐/ N ‐glycosides, C ‐glycosides exhibit more metabolic stability. We here disclose first example visible‐light‐promoted Cu‐catalyzed stereoselective ‐glycosylation. mild reaction conditions are compatible various carbohydrate substrates, as demonstrated a series monosaccharides disaccharide, amenable synthesis wide...

Herein, a non-classical C-saccharide linkage is reported via C5 radical of pentose or C6 hexose addition to Michael acceptors. C(sp3)-S cleaved glycosyl thianthrenium salts are developed as the agents. The reaction provides an efficient toolkit synthesize β-glycosyl substituted unnatural amino acids well for late-stage modification peptides.