以Saccharin/TEMPO高效催化氧化醇制备醛酮的研究

采用Saccharin/TEMPO共催化剂并在次氯酸钠NaClO作用下高效地催化氧化醇合成了醛或酮。筛选了溶剂及SAC/TEMPO用量等条件获得了最优工艺。以一系列的醇作为底物进行了研究,结果表明,高效地实现了对醇的氧化转化,产率可达95%,并且有良好的选择性。应用此共催化体系对醛或酮的制备具有广泛的适用性,是一种较好的方法。

Etiology of inflammatory bowel disease:A unified hypothesis

Inflammatory bowel disease(IBD),including both ulcerative colitis(UC) and Crohn's disease(CD),emerged and dramatically increased for about a century.Despite extensive research,its cause remains regarded as unknown.About a decade ago,a series of findings made me suspect that saccharin may be a key causative factor for IBD,through its inhibition on gut bacteria and the resultant impaired inactivation of digestive proteases and over digestion of the mucus layer and gut barrier(the Bacteria-Protease-Mucus-Barrier hypothesis).It explained many puzzles in IBD such as its emergence and temporal changes in last century.Recently I further found evidence suggesting sucralose may be also linked to IBD through a similar mechanism as saccharin and have contributed to the recent worldwide increase of IBD.This new hypothesis suggests that UC and CD are just two symptoms of the same morbidity,rather than two different diseases.They are both caused by a weakening in gut barrier and only differ in that UC is mainly due to increased infiltration of gut bacteria and the resultant recruitment of neutrophils and formation of crypt abscess,while CD is mainly due to increased infiltration of antigens and particles from gut lumen and the resultant recruitment of macrophages and formation of granulomas.It explained the delayed appearance but accelerated increase of CD over UC and many other phenomena.This paper aims to provide a detailed description of a unified hypothesis regardingthe etiology of IBD,including the cause and mechanism of IBD,as well as the relationship between UC and CD.

Science Letters:Simultaneous determination of fluoride, chloride, sulfate, phosphate, monofluorophosphate, glycerophosphate, sorbate, and saccharin in gargles by ion chromatography

Simple, reliable and sensitive analytical methods to determine anticariogenic agents, preservatives, and artificial sweeteners contained in commercial gargles are necessary for evaluating their effectiveness, safety, and quality. An ion chroma-tography (IC) method has been described to analyze simultaneously eight anions including fluoride, chloride, sulfate, phosphate, monofluorophosphate, glycerophosphate (anticariogenic agents), sorbate (a preservative), and saccharin (an artificial sweetener) in gargles. In this IC system, we applied a mobile phased gradient elution with KOH, separation by IonPac AS18 columns, and suppressed conductivity detection. Optimized analytical conditions were further evaluated for accuracy. The relative standard deviations (RSDs) of the inter-day's retention time and peak area of all species were less than 0.938% and 8.731%, respectively, while RSDs of 5-day retention time and peak area were less than 1.265% and 8.934%, respectively. The correlation coefficients for targeted analytes ranged from 0.999 7 to 1.000 0. The spiked recoveries for the anions were 90%~102.5%. We concluded that the method can be applied for comprehensive evaluation of commercial gargles.

Effect of bath composition and pulse electrodeposition condition on characteristics and microhardness of cobalt coatings

Nanocrystalline cobalt coatings were produced from cobalt sulfate based electrolytes by using pulse current electrodeposition technique.The effects of bath composition and electrodeposition condition on current efficiency,morphology,structure and hardness of the coatings were investigated and the optimum deposition condition was determined.It was found that increment of cobalt sulfate concentration and sodium dodecyl sulfate(SDS)concentration in the bath had a negligible effect on microhardness of the coatings,while they were effective on electrodeposition current efficiency.Adding saccharin to electrodeposition bath decreased crystallite size of hexagonal close-packed(hcp)cobalt films and increased their microhardness without significant effect on current efficiency.Smoother and less defective coatings were also obtained from baths containing SDS and saccharin.The results revealed that both the current efficiency and microhardness were changed by variation of peak current density and duty cycle.Besides change of smooth morphology of the coatings to needle-shaped one,crystallite sizes and preferred orientation also varied with increasing the current density and duty cycle.

Determination of saccharin in preserved fruits by High Performance Liquid Chromatography

Quantitative analysis of saccharin in preserved fruits was performed by High Performance Liquid Chromatography （HPLC）. The separation was observed on a reversed phase ODS C）8 column （4.6 × 250 mm）. Mobile phase system consisted of ammonium acetate buffer： Methanol （60：40 v/v） at a flow rate of 1.0 mL.min^-1, and UV detector was set at 235 nm. The calibration curve of saccharin was linear in the concentration range between 1 to 100 mg·L^-1）, while the detection limit of saccharin was found to be 0.08 mg.L^-1. The mean value of recovery was 98.24% with standard deviation of0.32% （n=12）. The proposed method was successfully applied to determine the amount of saccharin in 12 preserved fruits, commercially available in Chiang Mai local markets. The results showed that the saccharin contents were found in the range of 6.22-78.60 mg.kg^-1.

An Eco-Friendly Synthesis of Heterocyclic Moieties Condensed with Pyrazole System under Green Conditions and Their Biological Activity

The efficient, facile and green synthesis of 4-bromo pyrazolone by using N-bromo saccharine as valuable green reagent encouraged us to prepare some new fused heterocycles as furopyrazole, pyranopyrazole, imidazopyrazole, pyrazolothiazole, pyrazol thiazolopyrimidine, pyrazolothiazine, oxathinopyrazole, pyrazolobenzooxazine, and pyrazoloquinoxaline. The synthesis was carried out by a basic condensation of bromo pyrazolone 2 and a suitable reagent in a one-pot reaction using chitosan as a green basic catalyst. The reactions were carried out by microwave irradiation technique as a green source of energy as well as the conventional heating. The antioxidant activity of the prepared compounds was studied using 1,1-phenyl-2-picrylhydrazyl (DPPH) assay and their antibacterial activity against Gram-positive, Gram-negative bacteria and antifungal activity was evaluated.

Dietary saccharin sodium supplementation improves the production performance of dairy goats without residue in milk in summer

The purpose of this study was to investigate the effects of dietary saccharin sodium supplementation on production performance,serum biochemical indicators,and rumen fermentation of dairy goats in summer.Twelve Guanzhong dairy goats with similar body weight,days in milk,and milk yield were randomly divided into two dietary treatments:(1)CON:basal diet;(2)SS:basal diet+150 mg/kg saccharin sodium on the basis of dry matter.The experiment lasted 35 d,including 7 d for adaptation and 28 d for dietary treatments,sampling and data collection.Each dairy goat was housed individually in a clean separate pen with ad libitum access to diet and water.The goats fed SS diet had increased dry matter intake(DMI;P=0.037),4%fat corrected milk yield(P=0.049),energy corrected milk yield(P=0.037),milk protein yield(P=0.031),and total solids yield(P=0.036).Serum activity of aspartate aminotransferase(P=0.047)and concentrations of 70-kDa heat shock protein(P=0.090),malondialdehyde(P=0.092),and total protein(P=0.057)were lower in goats fed SS diet than those fed CON diet.Supplementation of saccharin sodium tended to increase activity of glutathione peroxidase in serum(P=0.079).The concentrations of rumen total volatile fatty acid(P=0.042)and butyrate(P=0.038)were increased by saccharin sodium supplementation.Dietary supplementation of saccharin sodium increased the relative abundance of Lachnobacterium(P=0.022),Pseudoramibacter(P=0.022),Shuttleworthia(P=0.025),and Syntrophococcus(P=0.037),but reduced the relative abundance of Prevotella_1(P=0.037)and Lachnospiraceae_UCG_008(P=0.037)in rumen.Saccharin sodium was observed in feces and urine of goats fed diet supplemented with saccharin sodium,but saccharin sodium was undetectable in the milk of goats receiving SS diet.In conclusion,administration of saccharin sodium was effective in increasing fat and energy corrected milk yield by increasing DMI and improving rumen fermentation and antioxidant capacity of dairy goats in summer.In addition,saccharin sodium residue was undetectable in the milk.

鼻腔冲洗在鼻部疾病治疗中的现况及研究进展

鼻腔冲洗（Nasal irrigation）是鼻部疾病局部治疗的方法之一,又称盥洗、灌洗或清洗,指借助某种装置,通过一定压力的将冲洗液输送到鼻腔、深入鼻窦,药液与鼻腔靶组织接触,将鼻腔内结痂及分泌物清除,达到清洁鼻腔、治疗等目的的治疗鼻部疾病的常用方法之一,此法易操作,花费低,方法简便已被广泛应用于鼻腔鼻窦多种疾病治疗。

Copper-catalyzed arenes amination with saccharins

A novel copper-catalyzed direct C–N formation reaction of simple arenes with cheap and pharmacological saccharin derivatives under relatively mild conditions was developed with arenes as limiting reagents.This work provided a new method for oxidative coupling of aromatic C(sp2)–H bonds and N–H bonds.

Water-Promoted Ring-Opening Reactions of N-Substituted Saccharins and Phthalimides by Amines

The reactions of N-substituted saccharins and phthalimides with amines were promoted by water.Various o-sulfamoyl benzamides and N,N′-disubstituted phthalamides were prepared in moderate to good yields.These reactions have prominent advantages,such as short reaction time,less by-products and simple isolation of the products.Water can probably stabilize the reaction intermediates and facilitate precipitation of the ring-opening products.When steric hindrance arose,hydrolytic compounds,either free acid or salts of the acids,were obtained.Possible reason for the formation of amine salts of o-sulfamoyl benzoic acids was proposed.

Synthesis and Biological Evaluation of Novel Saccharin Derivatives Containing 1,2,3-Triazole Moiety

A series of novel saccharin derivatives containing 1,2,3-triazole moiety was synthesized in satisfactory yields. The structures of all the compounds were elucidated and confirmed by Fourier transform infrared（FTIR） spectroscopy, ^1H and ^13C nuclear magnetic resonance（^1H NMR, ^13C NMR） spectroscopy, and high resolution mass spectrometry（HRMS）. The bioassays indicated that most of the title compounds displayed some extent herbicidal activities at 100 μg/mL.

Impact of smoking on nasal mucociliary clearance time in Kano metropolis,Nigeria

Background:Mucociliary clearance is an important defense mechanism in human upper and lower respiratory airways.Impairment of this process by certain conditions such as cigarette smoking can predispose to chronic infection and neoplasm of the nose and paranasal sinuses.Methods:This was a cross-sectional study conducted in Kano metropolis,Nigeria.Eligible adults were enrolled,a saccharine test was conducted,and the nasal mucociliary clearance time was assessed.Analysis of the result was carried out using Statistical Product and Service Solutions version 23.0.Results:There were 225 participants categorized into 75 active smokers(33.3%),74 passive smokers(32.9%),and 76 nonsmokers(33.8%,living in a smoking-free zone).The age range of the participants was between 18 and 50 years,with a mean age of(31.2±5.6)years.All participants were males.There were 139(61.8%)of Hausa-Fulani ethnic group,24(10.7%)Yoruba,18(8.0%)Igbo,and 44(19.5%)other ethnic groups.Findings in this study showed that the average mucociliary clearance time among active smokers was prolonged([15.25±6.20]min)compared to passive([11.41±4.25]min)and nonsmokers([9.17±2.76]min)respectively,with a statistical significance(F=33.59,P<0.001).Binary logistic regression revealed that the number of cigarettes smoked per day was an independent predictor of prolonged mucociliary clearance time(P=0.008,odds ratio=0.44,95%confidence interval=0.24–0.80).Conclusion:Active cigarette smoking is associated with prolonged nasal mucociliary clearance time.The number of cigarette sticks smoked per day was found to be an independent predictor of prolonged mucociliary clearance time.