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Stilbenes react with the hypervalent iodine compound (II) as nitrogen source to give intermediate imines which undergo iron catalyzed conversion into various benzamides in the presence of air.

The highly efficient asymmetric α-amination of β-keto esters and β-keto amides was realized by using a chiral N,N′-dioxide/Cu(I) complex. Under mild reaction conditions, a series of corresponding chiral α-amino dicarbonyl compounds were obtained in excellent yields (up to 98%) with excellent enantioselectivities (up to 95% ee).

Cancer remains a major killer worldwide. To search for novel naturally occurring compounds that are cytotoxic to cancer cells to be used as lead structures for drug development, five new steroids (1–5) along with seven known ones (6–12) were isolated from the rhizome of Anemarrhena asphodeloides Bge. Their structures were established by detailed spectral studies, including 1D-NMR, 2D-NMR, HR-ESI-MS and by comparison with literature data. These compounds exhibited different levels of growth inhibition against A549, HepG2, Hep3B, Bcap37 and MCF7 cell lines in vitro. Compounds 9, 10 and 11 showed potent inhibitory against all the tested cell lines with IC50 values ranging from 0.35 ± 0.15 to 25.53 ± 0.31 μM. The three compounds displayed stronger inhibitory activities against A549, HepG2 and Hep3B cell lines compared with the positive control 5-fluorouracil. The experimental data obtained permit us to identify the roles of the sugar moieties, hydroxyl group, double bond and F-ring with regard to their cytotoxic activities.

A new dimeric sesquiterpene, dicarabrol (1), together with three known sesquiterpenes, carabrol (2), 11(13)-dehydroivaxillin (3), and 2-desoxy-4-epi-pulchellin (4), were isolated from the whole plant of Carpesium abrotanoides L. Their structures were elucidated on the basis of spectroscopic analysis, and single crystal X-ray diffraction analysis. Compound 1 possessed a dimeric sesquiterpene core featured with a cyclopentane ring connecting two sesquiterpene lactone units rarely discovered in nature. Dicarabrol (1), as well as three known sesquiterpenes (2-4), had potent in vitro cytotoxicities against the K562, MCF-7, Hela, DU145, U937, H1975, SGC-7901, A549, MOLT-4, and HL60 cell lines with IC50 values ranging from 0.10 to 46.7 μM, while they showed significant antiviral (H1N1 and H3N2) activities. Furthermore, compounds 1, 3 and 4 displayed significant antimycobacterial activity (IC50 3.7, 6.0, and 7.6 μM, respectively).

A glucose-containing imidazolium salt β-1-imidazole-2,3,4,6-tetraacetyl-D-glucopyranosyl bromide was firstly used as efficient noncovalent organocatalyst to promote the solvent-free preparation of ortho-aminocarbonitriles via a four-component condensation of aromatic aldehyde, cyclohexanone, and 2 equiv of malononitrile at room temperature. Seven bonds were cleaved while four new bonds were formed and a six-membered ring was constructed in one-pot.

The reaction of tryptamines with allenoamides in the presence of BINOL-derived phosphoramidate ligated gold catalysts provides pyrroloindolines with enantioselectivities up to 99%.

Five new tigliane-type diterpenes (I)—(IV) are isolated along with four known phorbol ester analogues from the branches and leaves of Croton tiglium.

An efficient synthesis of 2-aminonaphthalenetricarbonitriles (IV) (15 examples) via multicomponent condensation of cyclohexanone with aromatic aldehydes and two equivalents of malononitrile is given.

The comproportionation between the low-valence sulfur atom in a thiosulfate and a high-valence S in a sulfinate efficiently affords asymmetric disulfides without additional oxidant.

The asymmetric nitroaldol reaction of nitroethane with aromatic, heteroaromatic, or α,β-unsaturated aldehydes gives the anti-β-nitroalcohols as main isomers.

Eight novel daphnane-type ditepenes, neogenkwanines A—H, are isolated along with seven known ones.

A chiral ytterbium(III)–N,N′-dioxide catalyst system has been developed for the catalytic direct asymmetric vinylogous Michael addition of 3-alkylidene oxindoles to chalcones, delivering the γ-substituted alkylideneoxindoles in high yields, enantioselectivities and good Z/E selectivities under mild reaction conditions.

Transamination of α-keto acids with transaminases and pyridoxamine phosphate is an important process to form optically active α-amino acids in biological systems. Various biomimetic transamination systems have been developed for carbonyl compounds including α-keto acid derivatives, fluoroalkyl ketones, and unactivated ketones with chiral vitamin B6 analogues, artificial transaminase mimics, chiral nitrogen sources, and chiral catalysts. This review provides a brief summary of this area.

An efficient synthesis of 7-alkyl-6H,7H-naphtho-[10,20:5,6]pyrano[3,2-c]chromen-6-ones by three-component condensation reaction of β-naphthol, aromatic aldehydes, and 4-hydroxycoumarin catalyzed by 1-methyl-3-(2-(sulfooxy)ethyl)-1H-imidazol-3-ium chloride is reported in good to excellent yields and short reaction times.

The regioselective reactions of luminol with 1,3-cyclohexanedione (or malononitrile) and aromatic aldehydes catalyzed by 2-1′-methylimidazolium-3-yl-1-ethyl sulfate were developed to synthesize 7-amino-3,4-dihydro-2H-indazolo[2,1-b]phthalazine-1,6,11(13H)-triones and 3,9-diamino-5,10-dihydro-5,10-dioxo-1H-pyrazolo[1,2-b]phthalazine-2-carbonitriles in good to excellent yields in short times.

A new method was developed to synthesize oxirane products from the reaction of diazocarbonyl substrates with aryl aldehydes by using Ag(I) N -heterocyclic carbene complex as the catalyst. A combination of N -heterocyclic carbene silver complex (IPrAgCl) with another silver salt (AgOTf) generated the catalytic active IPr-Ag + intermediate, which then catalyzed the epoxidation reaction.

The 3-phenylpropanoid-triacetyl sucrose esters, tomensides A-D (I), are isolated along with three known analogs from the leaves of Prunus tomentosa.

41 Title compounds of type (IV) are prepared by this new highly atom-economic one-pot procedure.

In the presence of NIS or N-iodophthalimide, 1,2,3-triazoles are found to react with pyrroles and indoles with high degree of N2-selectivity.

The asymmetric aldol cyclization of both β,γ-unsaturated α-keto esters and α-keto esters by using Y(OTf)3 and chiral bis(oxazoline) N,N′-dioxide as catalyst is developed.

Nine new 8-O-4' neolignans, named pinnatifidanin B I-IX (1-9), together with 9 known analogs (10-18) were isolated from the seeds of Crataegus pinnatifida. The structures of 1-18 were determined by spectroscopic methods, including 1D, 2D NMR, CD and HRESIMS analysis. Compounds 8-11, 17 and 18 displayed potent cytotoxic activities against human cancer cell lines, and most interestingly, none of the 6 compounds displayed inhibitory activity against human lung cell line (Mrc5). The 6 cytotoxic compounds are considered to be potential as antitumor agents, which could significantly inhibit the cancer cell growth in a dose-dependent manner and are probably safer than positive control drug.

A novel domino reaction between aminoacetophenone (I), malononitrile (II), and aromatic aldehydes (III) yields the title compounds (IV).

The efficient one-pot syntheses of Betti bases by the three-component reaction of aromatic aldehyde, 2-naphthalen, and acetonitrile (or benzamide) catalyzed by 1-methyl-3-(2-(sulfooxy)ethyl)-1H-imidazol-3-ium chloride is reported. The solvent can be recycled easily.

A novel Pd-catalyzed double C–S bond formation coupling reaction has been developed. This protocol, in which Na2S2O3 was used as sulfurating reagent in metal-catalyzed reactions, provides an efficient method for the synthesis of substituted 1,4-benzothiazine derivates, which are structural elements of numerous bioactivity molecules rendering this protocol attractive to both synthetic and medicinal chemistry.

A novel and practical protocol for the Au-catalyzed enantioselective [3 + 2] dipolar cycloaddition of N-allenyl amides with nitrones using modified BINOL-derived chiral phosphoramidate as ligands is developed.

This method tolerates a variety of functional groups and yields unsymmetrically substituted 1,3-diynes or 1,3,5-triynes with aryl and/or alkyl substituents.

An efficient method is elaborated for the synthesis of 6-methylenepyrazolopyrazolone (III) and 1-methylenehexahydropyrazolo[5,1-a]isoquinoline derivatives (X) by cycloaddition of N-allenyl amides (II) with corresponding azomethine imines (I) and (IX), respectively.

A quinine derivative is used as an efficient chiral catalyst for the asymmetric synthesis of trifluoromethyl aldimines (II) by [1,3]-proton shift of imines (I).

Worth its salt: An orgnaocatalytic asymmetric intramolecular aza-Michael reaction and one-pot bromination reaction of activated α,β-unsaturated ketones have been realized using a chiral bisguanidium salt. Optically enriched 2-aryl- and 2-alkyl-substituted dihydroquinones and brominated dihydroquinones could be obtained (up to 99% yield and 99% ee for the aza-Michael reaction; and up to 95% yield, 96:4 d.r., and 95% ee for the bromination reaction).

An asymmetric biomimetic transamination of aromatic ketones to optically active amines with o-HOPhCH2NH2 as amine source catalyzed by hydroquinine-derived chiral base is described. Up to 85% ee was obtained.

The first example of intermolecular decarboxylative benzylation of activated aliphatic carboxylate salts is presented.

It is found that the chiral bases (QUI) and (ALK) efficiently promote the asymmetric transamination of α-keto esters.

Transamination of α-keto esters efficiently proceeds in the presence of a benzyl amine and triethylamine as catalyst.

A highly efficient approach to indolo [1,2-a]quinoxaline derivatives through a Pd-catalyzed regioselective C–H olefination/cyclization sequence has been developed. This transformation has a wide range of substrates with various functional groups, and the corresponding heterocyclic products were obtained in good yields.

The Au-catalyzed treatment of alleneamides with electron-rich alkenes allows an efficient access to functionalized cyclobutanes.

In the presence of AuCl(PPh3)/AgSbF6, 1,4-allylic diols of type (I) undergo new ring expansion giving one-carbon higher keto homologues such as (II).

A highly efficient catalytic asymmetric vinylogous Mukaiyama–Michael reaction of the 2-silyloxyfuran with chalcone derivatives, catalyzed by a chiral N,N′-dioxide–scandium(III) complex, has been accomplished which tolerates a wide range of substrates. The reaction proceeds with complete regioselectivities, excellent diastereoselectivities (up to >99 : 1 dr) and good to excellent enantioselectivities (up to 94% ee) under mild conditions, delivering highly functionalized enantiomerically enriched anti-γ-substituted butenolides. The process is air-tolerant and easily manipulated with available reagents. In order to illustrate the synthetic potential of this reaction, the gram-scale synthesis and the elaboration of the butenolides have been explored. On the basis of the experimental results, a possible catalytic cycle and favorable stereorecognition model have been proposed.

Due to the bulky C-1 substituent and in the presence of boron trifluoride etherate, O-acylation of 2-chloropodophyllotoxin (I) proceeds stereoselectively with retention of the configuration at C-9.

This catalytic photoredox reaction shows high diastereoselectivity and affords highly substituted tetrahydroimidazole derivatives under mild conditions in excellent yields.

The cyclization of allylic acetates of type (I) and several structurally related analogues affords benzocyclohexanes in generally good yields.

The tandem process using base-catalyzed 1,3-H shift as the starting step is applicable to symmetrical aryl diynes (I) as well as unsymmetrical ones.

A mild, efficient, and highly stereoselective method to prepare 4-aminobenzopyrans with three consecutive stereogenic centers is reported.

A simple, new, and highly stereoselective method to prepare multifunctionalized 3-vinylcyclohexanols and oxabicyclooctanones like (III) is reported.