Efficacy of ornidazole for pericoronitis: a meta-analysis and systematic review.

Introduction: Timely and effective treatments of pericoronitis are very important. We aimed to evaluate the role of ornidazole in the treatment of pericoronitis, to provide insights for clinical pericoronitis treatment. Material and methods: The PubMed, Clinical trials, EMBASE, Science Direct, Cochrane Library, China National Knowledge Infrastructure (CNKI), Weipu and Wanfang databases were searched to find randomized controlled trials (RCTs) of ornidazole in the treatment of pericoronitis from the establishment of the database to March 15, 2023. Review Manager 5.3 software was used for meta-analysis. Results: A total of 16 RCTs involving 2004 patients were included. The results of the meta-analysis showed that the effective rate of ornidazole treatment was significantly higher than that of the routine treatment group (RR = 1.22, 95% CI (1.15, 1.29), p < 0.001). Ornidazole treatment was beneficial to reduce the oral bacterial density (MD = -26.13, 95% CI (-32.08, -21.51)), time to pain disappearance (MD = -0.64, 95% CI (-0.92, -0.17)) and time to disappearance of redness and swelling of the teeth crown (MD = -1.45, 95% CI (-2.43, -1.01)) compared to the routine treatment (all p = 0.05). No publication bias was found by the funnel plots and Egger test (p = 0.206). Conclusions: Ornidazole is effective in the treatment of pericoronitis, with more advantages. Still, the effects and safety of ornidazole in the treatment of pericoronitis need to be evaluated by more high-quality RCTs with larger sample sizes.

Oxidation of difluorocarbene and subsequent trifluoromethoxylation.

As a versatile intermediate, difluorocarbene is an electron-deficient transient species, meaning that its oxidation would be challenging. Herein we show that the oxidation of difluorocarbene could occur smoothly to generate carbonyl fluoride. The oxidation process is confirmed by successful trifluoromethoxylation, 18O-trifluoromethoxylation, the observation of AgOCF3 species, and DFT calculations.

Theoretical Study of pKa Values for Trivalent Rare-Earth Metal Cations in Aqueous Solution.

Molecular acidity of trivalent rare-earth metal cations in aqueous solution is an important factor dedicated to the efficiency of their extraction and separation processes. In this work, the aqueous acidity of these metal ions has been quantitatively investigated using a few theoretical approaches. Our computational results expressed in terms of pKa values agree well with the tetrad effect of trivalent rare-earth ions extensively reported in the extraction and separation of these elements. Strong linear relationships have been observed between the acidity and quantum electronic descriptors such as the molecular electrostatic potential on the acidic nucleus and the sum of the valence natural atomic orbitals energies of the dissociating proton. Making use of the predicted pKa values, we have also predicted the major ionic forms of these species in the aqueous environment with different pH values, which can be employed to rationalize the behavior difference of different rare-earth metal cations during the extraction process. Our present results should provide needed insights not only for the qualitatively understanding about the extraction and separation between yttrium and lanthanide elements but also for the prediction of novel and more efficient rare-earth metal extractants in the future.

pKa prediction for acidic phosphorus-containing compounds using multiple linear regression with computational descriptors.

Ninety-six acidic phosphorus-containing molecules with pKa 1.88 to 6.26 were collected and divided into training and test sets by random sampling. Structural parameters were obtained by density functional theory calculation of the molecules. The relationship between the experimental pKa values and structural parameters was obtained by multiple linear regression fitting for the training set, and tested with the test set; the R(2) values were 0.974 and 0.966 for the training and test sets, respectively. This regression equation, which quantitatively describes the influence of structural parameters on pKa , and can be used to predict pKa values of similar structures, is significant for the design of new acidic phosphorus-containing extractants. © 2016 Wiley Periodicals, Inc.

The asymmetric synthesis of CF3- or -CF2-substituted tetrahydroquinolines by employing a chiral phosphoric acid as catalyst.

CF(3)- or -CF(2)-containing tetrahydroquinolines have been asymmetrically synthesized from the reaction of fluorinated N-arylimines with benzyl N-vinylcarbamate in the presence of a chiral phosphoric acid.

Electrophilic fluoroalkylation of Ni(II) N-confused porphyrins with fluoroalkylarylsulfonium salts.

Experimental studies showed that Ni(II) N-confused porphyrins, treated with fluoroalkylarylsulfonium salts, can undergo an electrophilic fluoroalkylation at the inner 21-C position, leading to 21-fluoroalkylated Ni(II) N-confused porphyrins.