Elucidation of pineapple softening based on cell wall polysaccharides degradation during storage.

The degradation of cell wall polysaccharides in pineapple fruit during softening was investigated in the present study. Two pectin fractions and two hemicellulose fractions were extracted from the cell wall materials of 'Comte de Paris' pineapple fruit at five softening stages, and their compositional changes were subsequently analyzed. The process of softening of the fruit corresponded to an increase in the water-soluble pectin (WSP) and 1 M KOH-soluble hemicellulose (HC1) fractions, and a decrease in the acid-soluble pectin (ASP) fraction, which suggested the solubilization and conversion of cellular wall components.

One-pot synthesis of multi-substituted conjugated dienones by trapping allene carbocations with active ylides.

A Rh(II)/boron reagent co-catalyzed unprecedent transformation was established for the rapid construction of multi-substituted conjugated dienones under mild conditions by trapping allene carbocations with oxonium ylides from simple starting points in yields up to 85%. Two CC double bonds, one C-C and one C-O single bond were built in this one-pot reaction. The diversity-oriented strategy was also established to synthesize alkyne ether and dihydrofuran derivatives by a substrate-depended fashion.

Novel 2-phenyl-3-(Pyridin-2-yl) thiazolidin-4-one derivatives as potent inhibitors for proliferation of osteosarcoma cells in vitro and in vivo.

Due to unknown pathogenesis and unidentified drug target, no drug for the treatment of osteosarcoma (OS) has been launched to the market. Herein, thiazolidinone 1a was discovered as a hit compound by phenotypic screening with an in-house patrimonial collection of structural diversity. The following SAR (Structure-Activity Relationship) study affords the final water-soluble lead compound (R)-8i as a potential inhibitor for the proliferation of OS cells by the modulation of solubility of the compounds with remarkable cellular potency (IC = 21.

FeTPPCl/FeCl Co-Catalyzed One-Pot Green Synthesis of α-Diaryl-β-alkynol Derivatives via Propargylic Carbocation Chemistry.

A green and highly efficient one-pot method for α-diaryl-β-alkynol derivatives in water at room temperature was developed using the cocatalysis of a Lewis acid and meso-tetraphenylporphyrin iron(III) chloride (FeTPPCl). The unprecedented transformation was promoted by a modulation of the charge properties of propargylic carbocation chemistry and the use of an in situ-generated oxonium ylide as a matching nucleophile. The reaction was performed in water at room temperature with a highly step-economic manipulation in good to excellent yields and with a broad substrate scope.

Dual Functional Pd-Catalyzed Multicomponent Reaction by Umpolung Chemistry of the Oxygen Atom in Electrophiles.

A Pd-catalyzed multicomponent reaction was developed by trapping oxomium ylide with nitrosobenzene via Pd-promoted umpolung chemistry. The Pd catalyst plays two important roles: diazo compound decomposed catalyst and Lewis acid for the activation of nitrosobenzene. This strategy provides some insight into a new way for discovery of multicomponent methodology to construct complex molecules.

C(sp2)-H Bond Multiple Functionalization in Air for Construction of Tetrahydrocarbazoles with Continuous Quaternary Carbons and Polycyclic Diversification.

The C(sp)-H function of indole ketone with diazo compound via a rhodium(II)-catalyzed intramolecular electrophilic trapping reaction under mild conditions in air was demonstrated. The established methodology provided a highly efficient approach for direct synthesis of mutisubstituted tetrahydrocarbazoles with continuous quaternary carbons. The resulting products facilitate further modification to conveniently construct tetrahydrocarbazoles with additional fused heterocyclic rings.

Highly Regioselective Radical Transformation of -Sulfonyl-1,2,3-triazoles in Air.

The classic transformations of -sulfonyl-1,2,3-triazoles were processed via nitrogen anion (hydrolysis, etc.) and carbene intermediates, and no efficient examples via radical intermediates were developed. Here, we reported a catalyst-free radical chain transformation of -sulfonyl-1,2,3-triazoles to access an intermolecular oxidative C(sp)-H coupling to yield -selective products in air without any catalysts.

A Rh(ii)-catalyzed three-component reaction of 3-diazooxindoles with N,N-disubstituted anilines and glyoxylates for the synthesis of 3-aryl-3-substituted oxindoles.

A simple and effective method for the synthesis of 3-aryl-3-substituted oxindole derivatives via a [Rh]-catalyzed three-component reaction of 3-diazooxindoles with N,N-disubstituted anilines and glyoxylates is developed. This transformation is proposed to proceed through an intermolecular aldol-type trapping of zwitterionic intermediates.