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, imidazopyrazo...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.展开更多
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 infe...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.展开更多
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 reaction...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.展开更多
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） ...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.展开更多
文摘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.
文摘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.
基金We thank the National Natural Science Foundation of China(No.20802049)for financial support.
文摘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.
基金Supported by the National Natural Science Foundation of China（No.21302139）.
文摘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.
