Bioactive glass sol as a dual function additive for chitosan-alginate hybrid scaffold

Bioactive glass-chitosan-alginate hybrid scaffolds were fabricated using BG sol as a dual function additive, which behaves as both bioactive inorganic phase to confer the bioactivity and cross-linker to improve the structural stability and mechanical properties.     

Synthesis of arylstannanes by palladium-catalyzed desulfitative coupling reaction of sodium arylsulfinates with distannanes

A novel Pd-catalyzed desulfitative cross-coupling reaction of sodium arylsulfinates with hexaalkyl distannanes is realized, allowing the facile synthesis of functionalized arylstannanes with moderate to excellent yields. The successful implement of gram-scale synthesis and tandem Stille coupling reaction demonstrates the potential applications of this method in organic synthesis.     

Recent advances in the functionalization of allenes via radical process

This review is focused on the recent advances in the functionalization of allenes via radical process. Different radical partners including carbon radicals and heteroatom radicals are discussed in the reactions of allenes. Generally, the radical formed in situ would attack the allene at the central carbon leading to allyl radical intermediate. However, the formation of alkenyl radical intermediate from allene could be observed as well in some cases with high regioselectivity and stereoselectivity.     

Organocatalytic stereoselective conjugate addition of 3-substituted oxindoles with in situ generated ortho-quinone methides

A novel method for the stereoselective conjugate addition of 3-substituted oxindoles to in situ generated o-QMs was described. This process was catalyzed efficiently by a cinchonidine-derived squaramide catalyst in oil-water phase, furnishing the corresponding 3,3-disubsituted oxindole derivatives in moderate to high yields (up to 98%) with high stereoselectivities (up to 95%?ee, 15.4:1?dr). The utility of this reaction was also investigated by the gram-scale synthesis and derivatization of one of the products.     

Rheokinetic study of gel-breaking process of xanthan gum solution

The dynamic rheological behavior of xanthan gum (XG) during the gel-breaking process was studied in this work. Both experimental and numerical simulations were adopted to investigate the effects of temperature and added salt on the gel-breaking process. The results showed that the gel-breaking reaction is slowed down by the added salt, while temperature has a positive influence on the chemical degradation of XG. The novel rheokinetics equations were established to describe the gel-breaking process of XG and the simulated values are in good agreement with experimental data. The changes of the model parameters with respect to temperature and added salt are consistent with the experimental results obtained with rheometer, which verifies the feasibility of the established rheokinetics equations for characterizing the gel-breaking reaction of XG.     

A general powder dusting method for latent fingerprint development based on AIEgens

Powder dusting method is the most practically useful approach for latent fingerprint development in the crime scene. Herein, a general powder dusting method has been explored for latent fingerprint development based on aggregation-induced emission luminogens (AIEgens). A series of tetraphenylethene (TPE) derivatives with multiple diphenylamine (DPA), namely, TPE-DPA, TPE-2DPA and TPE-4DPA, were selected as candidates to dope with magnetic powders and applied for latent fingerprint development. After screening, the magnetic powder 3 doped with TPE-4DPA proves to be the best, in terms of fluorescent intensity, resolution and adhesiveness. Afterwards, the magnetic powder 3 was applied for visualization of latent fingerprint on various smooth and porous substrates, including glass, stainless steel, leaf, ceram, plastic bag, lime wall, wood and paper money. Specific details, such as island, core, termination and bifurcation, can be clearly observed for the fluorescent fingerprint images.     

In Situ Monitoring of RAFT Polymerization by Tetraphenylethylene‐Containing Agents with Aggregation‐Induced Emission Characteristics

A facile and efficient approach is demonstrated to visualize the polymerization in situ. A group of tetraphenylethylene (TPE)‐containing dithiocarbamates were synthesized and screened as agents for reversible addition fragmentation chain transfer (RAFT) polymerizations. The spatial‐temporal control characteristics of photochemistry enabled the RAFT polymerizations to be ON and OFF on demand under alternating visible light irradiation. The emission of TPE is sensitive to the local viscosity change owing to its aggregation‐induced emission characteristic. Quantitative information could be easily acquired by the naked eye without destroying the reaction system. Furthermore, the versatility of such a technique was well demonstrated by 12 different polymerization systems. The present approach thus demonstrated a powerful platform for understanding the controlled living radical polymerization process.     

Alkenylation of C(sp3)−H Bonds by Zincation/Copper‐Catalyzed Cross‐Coupling with Iodonium Salts

α‐Vinylation of phosphonates, phosphine oxides, sulfones, sulfonamides, and sulfoxides has been achieved by selective C?H zincation and copper‐catalyzed C(sp³)?C(sp²) cross‐coupling reaction using vinylphenyliodonium salts. The vinylation transformation proceeds in high efficiency and stereospecificity under mild reaction conditions. This zincative cross‐coupling reaction represents a general alkenylation strategy, which is also applicable for α‐alkenylation of esters, amides, and nitriles in the synthesis of β,γ‐unsaturated carbonyl compounds.     

TBAI-mediated regioselective 5-exo-dig iodinative oxocyclization of 2-alkynylbenzamides for the synthesis of isobenzofuran-1-imines and isobenzofurans

Alkyne-based regioselective functionalization is an important transformation method for the synthesis of a wide variety of organic products. In this work, a regioselective TBAI-mediated oxidative 5-exo-dig iodo-oxycyclization of 2-alkynylbenzamide is used for the synthesis of various isobenzofuran derivatives with excellent functional group tolerance and high reaction efficiency. We hypothesized that using water in a mixed solvent could change the reaction pathway and realize a high reaction regioselectivity. Furthermore, the application of the developed procedure was demonstrated by the synthesis of phthalazin-1(2H)-one and aryl-substituted isobenzofurans.     

Anti-inflammatory polyketides from the mangrove-derived fungus Ascomycota sp. SK2YWS-L

A pair of novel 2,3-diaryl indone derivatives (+)- and (?)-ascomindone D [(+)-1 and (?)-1, respectively], as well as two new prenylated polyketides ascomfurans C (2) and ascomarugosin A (3) were obtained from the culture of a mangrove endophytic fungus Ascomycota sp. SK2YWS-L together with three known compounds (4–6). The enantiomers (+)-1 and (?)-1 were purified through chiral HPLC separation, which represented the first example of resolving 2,3-diaryl indone atropisomers in natural products. The structures of the new compounds were determined on the basis of interpretation of spectroscopic data including X-ray diffractions and the absolute configurations of (+)-1 and (?)-1 were elucidated by ECD calculations. The biosynthesis pathway was proposed. In the anti-inflammatory assay, (+)-1 and (?)-1 exhibited potential anti-inflammatory effects by inhibiting against the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW 246.7 mouse macrophages with the IC₅₀ values of 17.0 and 17.1 μM, respectively.