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An unprecedented four-component defluorinative reaction of allylic fluorides, amidines, and Cs2CO3 for the convenient synthesis of valuable pyrimidine-containing amidino carbamates under transition-metal-free conditions was developed.

A simple and practical Cs2CO3-promoted method for the synthesis of 6-nitroindole derivatives from enaminones and nitroaromatic compounds has been developed.

An efficient defluorinative net-[3 + 3]-cyclization strategy for the construction of perfluoroalkyl-substituted pyrimidine derivatives by using a series of perfluoroalkyl alkynes and amidines as starting materials was developed. The present reaction proceeded successfully under transition-metal-free conditions to form two new C–N bonds and a new heterocyclic ring through a sequence of hydroamination, defluorination, and annulation. The desired pyrimidines could be obtained with good functional group tolerance and moderate to good yields. Moreover, the distinctive fluorine effects of perfluoroalkyl substituents are vital for tuning the reactivity of alkynes for the anticipated defluorinative annulation. The pendant π system would lower associated bond dissociation energy significantly compared to that of a nonactivated C(sp3)–F bond.

An efficient transition-metal-free hydrodefluorination reaction of trifluoromethyl alkenes for accessing gem-difluoroalkenes is developed. It was surprising to find that the phosphoryl anion is able to mediate the defluorination.

Synthetic strategies by making use of one-pot multi-step cascade reactions are of special interest. Herein, an efficient three-component tandem reaction of polyfluoroalkyl peroxides with sulfinates for the facile construction of fluoroalkylated tetrasubstituted furan derivatives has been developed. The combination of DABCO and Cs2CO3 was found to be essential for the success of the reaction. This modular and regioselective approach proceeded via an unprecedented sequence of successive defluorination, dual sulfonylation, and annulation relay, along with four C(sp3)–F bonds cleaved and two new C–S bonds formed. In addition, this transition metal-free C–F bond functionalization which is amenable to gram-scale synthesis occurred under mild reaction conditions and has broad substrate scope and excellent functional group tolerance. Moreover, this defluorinative protocol also enabled the late-stage functionalization of complex compounds, which could potentially find synthetic utility in drug discovery.

Efficient synthesis of fluoroalkylated tri(hetero)arylphosphine oxides from perfluoroalkyl ketones and phosphine oxides or phosphonates has been achieved via successive C(sp3)–F bond activation under mild reaction conditions. This approach involving new C(sp2)–P/C(sp2)–O bond formation and fluoroalkylated heterocycle construction distinguishes itself by its broad substrate scope and synthetic simplicity. Moreover, tri(hetero)arylphosphines could also be prepared in high yields by further reductive transformation.

The syntheses, crystal structures, and electrochemical of the transition metal coordination complexes, Cu(acac)2(EDO-TTF-3-py)2 (2) and Zn(acac)2(EDO-TTF-3-py)2 (3) are reported, where acac = acetylacetonate; EDO-TTF-3-py (L1) = 4,5-ethylenedioxy-3′-(3′-pyridyl)-tetrathiafulvalene). In the complexes 2 and 3, the ligand L1 is coordinated to the metal atom through pyridine nitrogen. The similarly oxidation potentials were observed for the ligand L1 and 2 and 3, indicating the negligible interaction between the ligand and the metal in solution.

The synthesis, crystal structures, and electrochemical properties of the coordination complexes, NiBr2(ept)2 and ZnBr2(ept)2 (ept = 4,5-ethylenedioxy-3′-(3′-pyridyl)-tetrathiafulvalene) are reported. Both complexes are mononuclear, with monodentate coordination of the ept ligand through the pyridine nitrogen. Cyclic voltammetry measurements for both complexes show a sizable interaction involving the electroactive ept ligand, with stabilization of the oxidized forms of the complexes.

In this study, comparative proteomics was used to investigate the interaction of Spodoptera exigua and Arabidopsis thaliana. By using 2-D electrophoresis of differentially expressed proteins, combined with high-throughput matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) and MALDI-TOF/TOF MS, the changes in the abundance of proteins induced by insect feeding were studied in A. thaliana. More than 1,100 protein spots were reproducibly detected on each gel. The intensities of 30 protein spots in particular changed significantly, showing differences in volume of at least twofold. Among these, 17 protein spots were upregulated, and 13 were downregulated following an 8-h insect feeding period. Nineteen insect-feeding-responsive proteins were identified, all of which were involved in metabolic regulation, binding functions or cofactor requirement of protein, cell rescue, and defense and virulence, as assessed by Munich Information Center for Protein Sequences function category. About 50% of these were involved in metabolism, including transketolase, S-adenosylmethionine synthase 3, 2,3-biphosphoglycerate-independent phosphoglycerate mutase, beta-ureidopropionase, GDP-d-mannose 3′,5′-epimerase, and fatty acid synthase. The identification of insect-feeding-responsive proteins on Arabidopsis provides not only new insights into insect stress but also a good start for further investigation of their functions. Understanding how the plant responses to insects in the proteomic level will provide tools for a better management of insect pest in the field.

Phosphatase of Regenerating Liver-3 (PRL-3) is a newly identified colorectal cancer metastasis-related protein, which is a 22 kDa non-classical protein tyrosine phosphatase with a C-terminal prenylation motif. In this study, the inhibition kinetics of protein tyrosine phosphatases (PTPs) by a fluorescent substrate, 6,8-difluoro-4-methylumbelliferyl phosphate (DiFMUP) was evaluated. PRL-3 exhibits classical Michaelis-Menten kinetics with a v max value of 11.3 μmol · L −1 · min −1 . Analysis of PRL-3 by a Michaelis-Menten plot and a double-reciprocal plot indicated that the inhibitor magnolol can cause K m to increase, but does not alter the v max value, which suggests the competitive inhibition of PRL-3. At the same time, it was found that DiFMUP is a more sensitive substrate for PRL-3 than para-nitro-phenyl phosphate (pNPP) that is more frequently used at present. Furthermore, the method of screening for PTPs by the use of DiFMUP was developed, which studied the acceptance of DiFMUP by other PTPs.

A pot experiment was conducted to study the effects of two controlled-release fertilizers CRFA (4% resin-coated, N: P2O5: K2O = 14: 14: 14) and CRFB (4% resin-coated, N: P2O5: K2O = 20: 8:10) on the nutrient uptake and growth of Chrysanthemum morifolium, with common compound fertilizer CCF (N: P2O5: K2O = 15: 15: 15) as the control. Six treatments were installed, i. e., CCF1 (CCF, 6 g N x pot(-1)), CCF2 (CCF, 3 g N x pot(-1)), CRFA1 (CRFA, 6 g x pot(-1)), CRFA2 (CRFA, 3 g x pot(-1)), CRFB1 (CRFB, 6 g x pot(-1)), and CRFB (CRFB, 3 g x pot(-1)). On the 30th day of applying common compound fertilizer CCF1 and CCF2, soil available N, P and K contents were 163.29 and 145.26 mg x kg(-1), 180.39 and 163.13 mg x kg(-1), and 300.08 and 213.15 mg x kg(-1), respectively, and decreased rapidly since then. In treatments CRFA1, CRFB1, CRFA2, and CRFB, soil available N content increased slowly, and reached the peak on the 60th day after fertilizing, being 129.51, 138.65, 118.36, and 126.31 mg x kg(-1), respectively. Soil available P content had the same variation trend. Its maximum concentration was 169.54 and 133.46 mg x kg(-1) in treatments CRFA1 and CRFA2 on the 30th day after fertilizing, and 137.13 and 84.68 mg x kg(-1) in treatments CRFB1 and CRFB2 on the 60th day after fertilizing, and decreased slowly then. The agronomic traits such as leaf area, leaf area index, branch number, flowering rate, flower number, and flower diameter, etc., in treatments CRFA and CRFB were obviously better than those of the control, and CRFB was better than CRFA, suggesting that CRFB more matched the nutrient demand of C. morifolium. Under the conditions of present experiment, applying CRFB2 obtained the highest yield.