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A nickel‐catalyzed reductive amidation of aryl sulfonium salts with isocyanates for amide synthesis via C−S bond cleavage was developed. The reactions proceeded smoothly at ambient temperature in the presence of nickel catalyst and manganese metal in DMF to give a variety of amides in moderate to good yields with wide functional group tolerance. [ABSTRACT FROM AUTHOR]

A tandem carbonyl reduction and hydrodefluorination of β‐trifluoromethyl enones with hydrosilanes under transition‐metal‐free conditions was developed for the synthesis of a variety of valuable gem‐difluorovinyl alcohols. The hydrosilane could act as both a reductive agent and a C(sp3)‐F bond‐breaking promoter under mild reaction conditions. Synthetically useful organofluorides, such as gem‐fluorophosphine alkene, gem‐difluorovinyl ketone, and fluorinated dihydrofuran derivatives could be readily constructed by further transformations of the obtained gem‐difluorovinyl alcohols. Moreover, the method features mild reaction conditions, operational simplicity, excellent functional group tolerance, and scalability. [ABSTRACT FROM AUTHOR]

An efficient palladium-catalyzed carbonylation of aryl fluorosulfates with aryl formates for the facile synthesis of esters was developed. The cross-coupling reactions proceeded effectively in the presence of a palladium catalyst, phosphine ligand, and triethylamine in DMF to produce the corresponding esters in moderate to good yields. Of note, functionalities or substituents, such as nitro, cyano, methoxycarbonyl, trifluoromethyl, methylsulfonyl, trifluoromethoxy, fluoro, chloro, bromo, methyl, methoxy, N,N-dimethyl, and [1,3]dioxolyl, were well-tolerated in the reactions, which could be kept for late-stage modification. The reactions employing readily available and relatively robust aryl fluorosulfates as coupling electrophiles could potentially serve as an attractive alternative to traditional cross-couplings with the use of aryl halides and pseudohalides as substrates. [ABSTRACT FROM AUTHOR]

AIM: To investigate the clinical effect of Ranibizumab combined with photodynamic therapy(PDT)for wet type age-related macular degeneration(wAMD)and the effect on the serum neovascularization factors. METHODS: Totally 68 cases(68 eyes)of wAMD patients treated with PDT in our hospital from January 2014 to June 2016 were analyzed retrospectively. Among them, 34 patients were treated by photodynamic therapy(control group)and 34 patients were treated by combination of photodynamic therapy and ranibizumab(treatment group). Comparison of BCVA, mean retinal thickness and central macular thickness(CMT)and serum neovascularization regulatory factors before and after treatment were taken between the two groups. RESULTS: Before treatment, there was no significant difference on the BCVA, the average retinal thickness and the CMT value between the two groups(P>0.05). At 3, 6 and 12mo after treatment, the BCVA, average retinal thickness and CMT in both groups were significantly lower than those before treatment(PPP>0.05). Three months after treatment, VEGF, PDGF and ES in both groups were significantly lower than those before treatment(PPCONCLUSION: The wAMD patients treated with ranibizumab combined with photodynamic therapy can achieve a more significant clinical effect, and more effectively reduce the level of serum neovascularization regulators.

Hydroxylation of aryl sulfonium salts could be realized by utilizing acetohydroxamic acid and oxime as hydroxylative agents in the presence of cesium carbonate as a base, leading to a variety of structurally diverse hydroxylated arenes in 47–95% yields. In addition, the reaction exhibited broad functionality tolerance, and a range of important functional groups (e.g., cyano, nitro, sulfonyl, formyl, keto, and ester) could be well amenable to the mild reaction conditions. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Cross‐electrophile coupling of triazine esters with aryl bromides could be facilely accomplished by employing nickel as catalyst, magnesium as metal mediator, and lithium chloride as additive. The reactions proceeded efficiently in THF at room temperature through C—O bond activation to afford an array of structurally different diaryl ketones in moderate to good yields with wide functional group tolerance. Control experiments showed that nickel, magnesium, lithium chloride, and THF are all indispensable for the good performance of the coupling reaction. Preliminary mechanistic exploration indicated that in situ formed arylmagnesium reagent by the insertion of magnesium into aryl bromide might serve as the key intermediate of the cross‐coupling. The method which avoids the utilization of moisture‐labile and relatively difficult‐to‐obtain organometallics is step‐economical, cost‐efficient, and operationally simple, potentially serving as an attractive alternative to documented methods. [ABSTRACT FROM AUTHOR]

A H2O-promoted and (NH4)2CO3-enabled deiodoamination and defluoroiminization reaction of fluoroalkyl alkenes has been developed under transition-metal-free conditions. Structurally important fluoroalkylated 1,5-diazapentadienes were obtained in excellent Z-selectivity with good functional group tolerance. The versatility of the method was illustrated in the synthesis of valuable organofluorides from the obtained products. Compared to traditional synthetic methods, several apparent limitations, including distillation for purification, multistep manipulation, harsh reaction conditions, moisture exclusion, and the use of toxic/sensitive reagents, could be avoided. The key to the success of the reaction is the use of (NH4)2CO3 as a commercially available, inexpensive, low-toxic, and efficient NH2/NH source and water as a C(sp3)–F bond cleavage promoter. Moreover, the distinctive fluorine effects of perfluoroalkyl substituents on substrates are also vital for enhancing the reaction efficiency. [ABSTRACT FROM AUTHOR]

AIM: To investigate the correlation of matrix metalloproteinase -9(MMP-9), glycated albumin(GA), glycosylated hemoglobin(HbA1c)and adipokines(including visfatin, resistin and leptin)with diabetic retinopathy(DR). METHODS: From March 2015 to March 2017, 74 patients with DR were treated in our hospital, including 40 patients(80 eyes)with non proliferative diabetic retinopathy(NPDR)and 34 patients(68 eyes)with proliferative diabetic retinopathy(PDR), and diabetes mellitus 40 patients(80 eyes)with non DR(NDR)and 40 healthy volunteers(80 eyes)were selected as controls, the levels of MMP-9, GA, HbA1c, visfatin, resistin and leptin in each group were detected. RESULTS: PDR group visfatin was 4.41±0.82ng/mL, was significantly lower than the NPDR group, NDR group and control group(PPPPrs=0.523, 0.461 and 0.414, Prs=-0.433, Prs=0.401 and 0.460, PCONCLUSION: MMP-9, GA, HbA1c, and adipokines may play a role in the development and progression of DR, in which MMP-9 is associated with adipokines, both are not significantly related to the levels of GA and HbA1c.

The distinctive hydrophobic hydration effect in the aqueous solution contributes to the success of the phospha‐Michael reaction between β‐CF3‐β,β‐disubstituted enones and diarylphosphine oxides, providing an access to biologically relevant γ‐ketophosphine oxides bearing a sterically highly congested CF3‐ and P(O)‐tetrasubstituted carbon center. More importantly, the resulting products could be further transformed into densely functionalized γ‐ketophosphine oxides containing a CF3‐ and P(O)‐tetrasubstituted carbon center. [ABSTRACT FROM AUTHOR]

The distinctive fluorine effects on "on-water" chemistry have remained less explored. In this work, an "on-water" reaction of β-trifluoromethylated enones with phosphine oxides was developed for the preparation of highly functionalized gem-difluorodienes with excellent Z-selectivity. The reaction occurred through a well-designed tandem phospha-Brook rearrangement and defluorination sequence under transition-metal-free conditions in water solution, which efficiently overcame some competitive side reactions, such as hydrodefluorination, 1,4-nucleophilic addition, and phosphorylation. The success was attributed to favorable H-bonding interactions at the water–organic phase boundary which could activate the substrates and enhance the reaction selectivity. [ABSTRACT FROM AUTHOR]

A step‐economical and operationally simple nickel‐catalyzed cross‐electrophile coupling of aryl phosphates with aryl bromides through C−O bond cleavage, which precluded the employment of relatively moisture‐labile and unreadily available organometallics, was developed. The reaction proceeded smoothly in the presence of magnesium turnings and lithium chloride in THF to afford the corresponding biaryls in moderate to good yields with reasonable functionality tolerance. [ABSTRACT FROM AUTHOR]

An aerobic coupling of benzhydryl phosphonium salts with simple alkenes for accessing trisubstituted olefins is developed under metal‐free, catalyst‐free, and additive‐free conditions. New C(sp3)−C(sp2) bond is constructed via the C−P and C−H bond functionalization by synergistically using O2 as a "green" oxidant and DMSO as a promoter. The method also distinguishes itself by its broad substrate scope and synthetic potential. Particularly, the use of 1,3,5‐trimethoxybenzene fragment in the resulting products as a carbon‐based leaving group for further transformations is proved to be feasible. [ABSTRACT FROM AUTHOR]

Research interest in defluorinative functionzalization by means of the distinctive fluorine effect of organofluorides has led to rapid development in this topic. Herein, we reported 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. The synthetic linchpin for realizing the multi-bonding tandem protocol relied on the directed function of the α-positioned hydroxyl group and the activating effect of the perfluoroalkyl substituent in allylic fluorides. Moreover, cesium carbonate served as a green carbonyl equivalent for formal CO capture. Mechanistic studies revealed that the reaction proceeded via a possible cyclic carbonate intermediate. [ABSTRACT FROM AUTHOR]

The reaction of non‐fluorinated silyl enol ether with alkyne is useful for the synthesis of β,γ‐unsaturated carbonyl compounds. However, most of the existing methods for realizing such organic transformation usually employ stoichiometric amounts of relatively expensive Lewis acids/metallic salts. Herein, an iron(III)‐catalyzed difluoroalkylation of aryl alkynes with difluoroenol silyl ether was developed. The reactions proceeded smoothly in the presence of a catalytic amount of iron(III) chloride, stoichiometric amounts of trimethylsilyl chloride, and 4 Å molecular sieves in dichloroethane (DCE) to afford the corresponding α‐alkenyl‐α,α‐difluoroketones in modest to good yields. Remarkably, among the various metallic salts screened, cheap and less‐toxic iron(III) salt was found to be the most efficient Lewis acid catalyst for the present reaction. In addition, in the absence of iron(III) chloride or trimethylsilyl chloride, either no reaction occurred or considerably reduced reaction performance was observed. Moreover, the use of Brønsted acid to replace iron(III) chloride as reaction catalyst failed to promote the reaction. The reaction could be scaled up and the obtained difluoroalkylated carbonyl compound serves as a versatile building block which could be subjected to late‐stage diversification to be converted into useful organic molecules containing CF2H and CF2CF2 moieties. Deuterated experiments showed that the proton in the generated alkene product should originate from trace amounts of water present in the reaction system. [ABSTRACT FROM AUTHOR]