The synthetic process for 2,2-dimethyl-5-nitro-5-nitroso-1,3-dioxane（DMNNDO） was improved by using tri（hydroxymethyl）nitromethane and acetone as starting materials through a ＂one-pot＂ method combined with alkali...The synthetic process for 2,2-dimethyl-5-nitro-5-nitroso-1,3-dioxane（DMNNDO） was improved by using tri（hydroxymethyl）nitromethane and acetone as starting materials through a ＂one-pot＂ method combined with alkaline hydrolysis and nitrosation reactions. The yield of DMNNDO was increased from 37% to 45%. The structure of DMNNDO was characterized by IR,^1H NMR,^13 C NMR,and elemental analysis. Also the thermal decomposition of DMNNDO was studied by using DSC and TG-DTG to find that there are primarily two exothermic decomposition processes between 90 and 300 oC. The crystal structure of DMNNDO was studied by X-ray single-crystal diffraction for the first time. The molecular structure exists as a dimeric form due to the presence of nitroso group. The crystal belongs to monoclinic system,space group C2/c with a = 14.515（3）,b = 9.955（2）,c = 11.897（2） °,β = 98.500（3）°,V = 1.6998（2） nm^3,Z = 8,D_c = 1.486 g×cm^-3,μ = 0.128 mm^-1,F（000） = 800,S = 1.055,R = 0.0358 and wR = 0.0917. In particular,DMNNDO could be easily hydrolyzed in hydrous systems and the hydrolysis mechanism in CDCl_3 was revealed by means of NMR monitoring.展开更多
Based on theoretical calculation of electronegativity of groups of flotation reagent and method of infrared adsorption spectroscopy,the collection and adsorption of α-nitroso-β- naphthol in hematite flotation have b...Based on theoretical calculation of electronegativity of groups of flotation reagent and method of infrared adsorption spectroscopy,the collection and adsorption of α-nitroso-β- naphthol in hematite flotation have been studied.The chemical adsorption seems to be predominant owing to formation of pentacyclic nitrosyl chelate compound by atoms of nitrosyl bond in α-nitroso-β-naphthol together with Fe(Ⅲ)on hematite surface.Mean- while,the nonuniform multilayer physical adsorption is also occurred.展开更多
The paraffin wax was used as a diluent for 1-nitroso-2-naphthol(HA) and trioctylphosphine oxide(TOPO) in the extraction of lanthanides at 70℃. The composition of the extracted species was given as LnA_3(TOPO)_2 by me...The paraffin wax was used as a diluent for 1-nitroso-2-naphthol(HA) and trioctylphosphine oxide(TOPO) in the extraction of lanthanides at 70℃. The composition of the extracted species was given as LnA_3(TOPO)_2 by means of the slope analysis. The variation of the synergistic extraction equilibrium constant(K_ sex) was investigated at 60～80℃, and the thermodynamic data were calculated. The dependence of separation factors on temperature was also studied.展开更多
The suitability of 1-nitroso-2-naphthol(NN) as a complexing agent for on-line preconcentration of cobalt eluted on the C_(18) microcolumn by means of the FI-FAAS system was tested. Various parameters affecting the com...The suitability of 1-nitroso-2-naphthol(NN) as a complexing agent for on-line preconcentration of cobalt eluted on the C_(18) microcolumn by means of the FI-FAAS system was tested. Various parameters affecting the complex formation and its elution were optimized. A 2.3×10^(-3) mol/L reagent solution and the aqueous sample solution acidified with 0.1% (volume fraction) nitric acid were on-line mixed (6.4 mL/min) on a reaction coil set at (65±1)℃ and flowed through the microcolumn for 30 s. The pH of the mixed solution was adjusted to 3—4 with HNO_3(1 mol/L) or NaOH(1 mol/L). The adsorbed complexes in the microcolumn were eluted into the nebulizer of FAAS in 10 s with ethanol acidified with 1% HNO_3(3.0 mL/min). A good precision(1.6% for 100μg/L Co(Ⅱ), n=10), a high enrichment factor 17.2, with detection limit (3σ) 3.2μg/L, and sample throughput (90 h^(-1)) were obtained. The method was applied to the certified reference materials(CRMs), NBS-362 and NBS-364, for the determination of cobalt and the results were in good agreement with the certified values.展开更多
The extraction behavior of Sm(III), Eu(III),Er(III) and Yb(III) with 1- nitroso -2-naphthol (HA) in paraffin has been studied. The composition of,extracted complexes has been determined to be LnA(3) by slope analysis ...The extraction behavior of Sm(III), Eu(III),Er(III) and Yb(III) with 1- nitroso -2-naphthol (HA) in paraffin has been studied. The composition of,extracted complexes has been determined to be LnA(3) by slope analysis method. The effect of temperature on extraction system is also investigated and thermodynamic parameters are obtained.展开更多
To study the inhibiting effects of S-Nitroso-Glutathione （GSNO） on sporulation process of Eimeria tenella （E. tenella） oocysts by detecting the sporulation rate, GSNO as nitric oxide donor was used to treat E. ten...To study the inhibiting effects of S-Nitroso-Glutathione （GSNO） on sporulation process of Eimeria tenella （E. tenella） oocysts by detecting the sporulation rate, GSNO as nitric oxide donor was used to treat E. tenella oocysts sporulated for different times; Several kinds of antioxidants and oxidants were used to investigate the inhibitory effects of GSNO on sporogony process of E. tenella oocysts. The results showed that GSNO still inhibited the oocysts sporulated 10 h, but had few inhibiting effect on the oocysts sporulated for 14 h; the antioxidants, such as Vitamin C （VC）, mannitol and sodium salicylate, could not eliminate the inhibitory effects of GSNO on oocysts; neither did the ferrous sulfate （FeSO4） nor Dithiothreitol （DTT）. However, the oxidants, potassium dichromate （K2Cr2OT） and potassium permanganate （KMnO4） could obviously repress the effects of GSNO on oocysts. At present, the inhibitory mechanism of GSNO on unsporulated oocysts was still unclear.展开更多
Nitrosonaphthol dyes and other corresponding analogues were synthesised from 1-Naphthol. The dyes were applied onto chrome and vegetable tanned leather upon characterization. The results indicate that the dye bath exh...Nitrosonaphthol dyes and other corresponding analogues were synthesised from 1-Naphthol. The dyes were applied onto chrome and vegetable tanned leather upon characterization. The results indicate that the dye bath exhaustion was better on chrome tanned leather than on vegetable tanned leather. This may be attributed to the chelating effect of chrome on leather and the higher temperature of dyeing the chrome tanned leather compared with the vegetable tanned leather. The fastness properties of the dyes of washing ranging from (3 - 5), perspiration on acid (4 - 5), alkaline (4 - 5) and light (4 - 7) were impressive on both vegetable and chrome tanned leather respectively.展开更多
Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich reactivity.The versatile profile of these compounds allows them to function as electrophiles,nucle...Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich reactivity.The versatile profile of these compounds allows them to function as electrophiles,nucleophiles,diradicals,and radical acceptors in diverse transformations.In recent years,notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions.Various nitroso compounds like nitrosoarenes,acyloxy nitroso compounds,N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access.In this review,we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds,with particular emphasis on their role as bifunctional reagents and acceptors of radicals,carbenes and nitrenes.展开更多
In this paper, it is evidenced by the quantitative structu re-carcinogenic activity relation-ship (QSCAR) and the pattern recognition treatment of N-nitroso compounds (NNC) that thekey step of carcinogenesis induced b...In this paper, it is evidenced by the quantitative structu re-carcinogenic activity relation-ship (QSCAR) and the pattern recognition treatment of N-nitroso compounds (NNC) that thekey step of carcinogenesis induced by NNC is the cross-linking on the complementary basepair of DNA, through the bifunctional alkylation between α-carbon and another carbonwithin the same chain. The alkylation by the α-carbon atom is through the diazonium salt,but that by the atom other than the α-position is through the active ester formed from thehydroxylated metabolite of the chain. Therefore, the alkylation by the β-position of NNC,or by its γ-position under suitable conditions, of which the distances from the α-positionboth approach 2. 80-3. 00 A, would be the most favourable positions along with the α-posi-tion for the cross-linking to occur between the complementary base pairs of DNA, whichwill yield the carcinogenic activity of NNC. The above conception of bifunctional alkyla-tion can reduce the QSCAR of NNC to a reasonable structure-chemical reactivity relationshipunder the complex biological conditions, and is the successful extension of the Di-regiontheory to the carcinogenesis mechanism of the important NNC series. In the light of theabove viewpoint, for 153 NNCs including the nitrosamines and nitrosamides which havebeen tested reliably with animals, the correct discrimination ratio by quantitative patternrecognition according to carcinogenic activity indexes divided into 5 degrees comes up to ashigh as 97%.展开更多
目的:研究胃萎方对信号转导及转录激活蛋白3(Signal Transducer and Activator of Transcription 3,STAT3)/核因子-κB(Nuclear Factor-κB,NF-κB)信号通路的调控作用,探讨胃萎方对胃癌前病变(Precancerous Lesion of Gastric Cancer,P...目的:研究胃萎方对信号转导及转录激活蛋白3(Signal Transducer and Activator of Transcription 3,STAT3)/核因子-κB(Nuclear Factor-κB,NF-κB)信号通路的调控作用,探讨胃萎方对胃癌前病变(Precancerous Lesion of Gastric Cancer,PLGC)的疗效及作用机制。方法:从70只雄性Wistar大鼠中随机选择20只作为空白组,其余50只为造模组。采用N-甲基-N’-硝基-N-亚硝基胍(MNNG)诱导GPL大鼠实验模型。14周后,对随机选择的造模组大鼠10只进行胃组织学分析,确认造模成功,造模组剩余40只大鼠随机分为模型组、胃萎方治疗组各20只。使用胃萎方干预后,观察大鼠体质量增长、胃黏膜组织结构变化,以及血清胃蛋白酶原(Pepsinogen,PG)Ⅰ,PGⅡ和胃泌素的浓度,并检测NF-κB p65和STAT3的基因及蛋白表达。结果:与空白组比较,模型组大鼠体质量增长缓慢,胃黏膜组织细胞异型增生明显,血清PGⅠ、胃泌素水平和PGⅠ/PGⅡ比值显著降低,胃黏膜NF-κB/STAT3信号通路被激活;与模型组比较,胃萎方治疗组大鼠整体情况改善,胃黏膜组织结构重塑、萎缩性胃黏膜和非典型腺上皮减少,PGⅠ/PGⅡ比值和胃泌素水平增加(P<0.01),NF-κB p65和STAT3的mRNA及蛋白的表达受到一定程度的抑制(P<0.05)。结论:胃萎方能够通过抑制NF-κB/STAT3信号通路逆转MNNG诱导的大鼠GPL,为胃萎方的临床应用提供了基础证据。展开更多
Stomach carcinoma is still the leading cause of cancer death in China and the second one in the world. Its possible causes include: A) chemical factors such as intragastric formation of N-nitroso compounds (NOC) and h...Stomach carcinoma is still the leading cause of cancer death in China and the second one in the world. Its possible causes include: A) chemical factors such as intragastric formation of N-nitroso compounds (NOC) and high salt intake; B ) biological factors such as infection of Helicobacter pylori and biotoxins intake; and C ) nutritional factors such as deficiency of vitamin C, selenium, and other antioxidants. Nitrogenous precursors of NOC, e.g., alkylamines, alkylureas, alkylguanidines, and alkylamides, occur widely in nature and potential nitrosating agents, e.g., nitrite (NO2-) and NOx (the gaseous oxides of nitrogen ) are similarly widespread. Relationship between exposure to NOC and causes of human cancer was investigated extensively ten years ago. Results indicated that the exposures of NOC might contribute to the occurrences of malignancy in the upper digestive tracts including stomachs. It was also observed that both high salt intake and deficiency of some micronutrients enhanced NOC-induced carcinogenicity. Recent studies show that infection of H. pylori can lead to atrophic gastritis and achlorhydria, and promote endogenous formation of NOC indirectly[1] . Much attention has been paid to stomach cancer and NOC regarding the characterization of natural N-nitrosamides in human environment in the 1990s.展开更多
文摘The synthetic process for 2,2-dimethyl-5-nitro-5-nitroso-1,3-dioxane（DMNNDO） was improved by using tri（hydroxymethyl）nitromethane and acetone as starting materials through a ＂one-pot＂ method combined with alkaline hydrolysis and nitrosation reactions. The yield of DMNNDO was increased from 37% to 45%. The structure of DMNNDO was characterized by IR,^1H NMR,^13 C NMR,and elemental analysis. Also the thermal decomposition of DMNNDO was studied by using DSC and TG-DTG to find that there are primarily two exothermic decomposition processes between 90 and 300 oC. The crystal structure of DMNNDO was studied by X-ray single-crystal diffraction for the first time. The molecular structure exists as a dimeric form due to the presence of nitroso group. The crystal belongs to monoclinic system,space group C2/c with a = 14.515（3）,b = 9.955（2）,c = 11.897（2） °,β = 98.500（3）°,V = 1.6998（2） nm^3,Z = 8,D_c = 1.486 g×cm^-3,μ = 0.128 mm^-1,F（000） = 800,S = 1.055,R = 0.0358 and wR = 0.0917. In particular,DMNNDO could be easily hydrolyzed in hydrous systems and the hydrolysis mechanism in CDCl_3 was revealed by means of NMR monitoring.
文摘Based on theoretical calculation of electronegativity of groups of flotation reagent and method of infrared adsorption spectroscopy,the collection and adsorption of α-nitroso-β- naphthol in hematite flotation have been studied.The chemical adsorption seems to be predominant owing to formation of pentacyclic nitrosyl chelate compound by atoms of nitrosyl bond in α-nitroso-β-naphthol together with Fe(Ⅲ)on hematite surface.Mean- while,the nonuniform multilayer physical adsorption is also occurred.
文摘The paraffin wax was used as a diluent for 1-nitroso-2-naphthol(HA) and trioctylphosphine oxide(TOPO) in the extraction of lanthanides at 70℃. The composition of the extracted species was given as LnA_3(TOPO)_2 by means of the slope analysis. The variation of the synergistic extraction equilibrium constant(K_ sex) was investigated at 60～80℃, and the thermodynamic data were calculated. The dependence of separation factors on temperature was also studied.
基金Supported by Zhejiang Natural Science Foundation of China.
文摘The suitability of 1-nitroso-2-naphthol(NN) as a complexing agent for on-line preconcentration of cobalt eluted on the C_(18) microcolumn by means of the FI-FAAS system was tested. Various parameters affecting the complex formation and its elution were optimized. A 2.3×10^(-3) mol/L reagent solution and the aqueous sample solution acidified with 0.1% (volume fraction) nitric acid were on-line mixed (6.4 mL/min) on a reaction coil set at (65±1)℃ and flowed through the microcolumn for 30 s. The pH of the mixed solution was adjusted to 3—4 with HNO_3(1 mol/L) or NaOH(1 mol/L). The adsorbed complexes in the microcolumn were eluted into the nebulizer of FAAS in 10 s with ethanol acidified with 1% HNO_3(3.0 mL/min). A good precision(1.6% for 100μg/L Co(Ⅱ), n=10), a high enrichment factor 17.2, with detection limit (3σ) 3.2μg/L, and sample throughput (90 h^(-1)) were obtained. The method was applied to the certified reference materials(CRMs), NBS-362 and NBS-364, for the determination of cobalt and the results were in good agreement with the certified values.
文摘The extraction behavior of Sm(III), Eu(III),Er(III) and Yb(III) with 1- nitroso -2-naphthol (HA) in paraffin has been studied. The composition of,extracted complexes has been determined to be LnA(3) by slope analysis method. The effect of temperature on extraction system is also investigated and thermodynamic parameters are obtained.
文摘To study the inhibiting effects of S-Nitroso-Glutathione （GSNO） on sporulation process of Eimeria tenella （E. tenella） oocysts by detecting the sporulation rate, GSNO as nitric oxide donor was used to treat E. tenella oocysts sporulated for different times; Several kinds of antioxidants and oxidants were used to investigate the inhibitory effects of GSNO on sporogony process of E. tenella oocysts. The results showed that GSNO still inhibited the oocysts sporulated 10 h, but had few inhibiting effect on the oocysts sporulated for 14 h; the antioxidants, such as Vitamin C （VC）, mannitol and sodium salicylate, could not eliminate the inhibitory effects of GSNO on oocysts; neither did the ferrous sulfate （FeSO4） nor Dithiothreitol （DTT）. However, the oxidants, potassium dichromate （K2Cr2OT） and potassium permanganate （KMnO4） could obviously repress the effects of GSNO on oocysts. At present, the inhibitory mechanism of GSNO on unsporulated oocysts was still unclear.
文摘Nitrosonaphthol dyes and other corresponding analogues were synthesised from 1-Naphthol. The dyes were applied onto chrome and vegetable tanned leather upon characterization. The results indicate that the dye bath exhaustion was better on chrome tanned leather than on vegetable tanned leather. This may be attributed to the chelating effect of chrome on leather and the higher temperature of dyeing the chrome tanned leather compared with the vegetable tanned leather. The fastness properties of the dyes of washing ranging from (3 - 5), perspiration on acid (4 - 5), alkaline (4 - 5) and light (4 - 7) were impressive on both vegetable and chrome tanned leather respectively.
基金supported by the National Natural Science Foundation of China(22301292,21971001)the Distinguished Young Research Project of Anhui Higher Education Institution(2023AH020003)Armido Studer thanks the Deutsche Forschungsgemeinschaft(DFG)for funding(STU 280/92-1)。
文摘Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich reactivity.The versatile profile of these compounds allows them to function as electrophiles,nucleophiles,diradicals,and radical acceptors in diverse transformations.In recent years,notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions.Various nitroso compounds like nitrosoarenes,acyloxy nitroso compounds,N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access.In this review,we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds,with particular emphasis on their role as bifunctional reagents and acceptors of radicals,carbenes and nitrenes.
基金Project supported the National Natural Science Foundation of China.
文摘In this paper, it is evidenced by the quantitative structu re-carcinogenic activity relation-ship (QSCAR) and the pattern recognition treatment of N-nitroso compounds (NNC) that thekey step of carcinogenesis induced by NNC is the cross-linking on the complementary basepair of DNA, through the bifunctional alkylation between α-carbon and another carbonwithin the same chain. The alkylation by the α-carbon atom is through the diazonium salt,but that by the atom other than the α-position is through the active ester formed from thehydroxylated metabolite of the chain. Therefore, the alkylation by the β-position of NNC,or by its γ-position under suitable conditions, of which the distances from the α-positionboth approach 2. 80-3. 00 A, would be the most favourable positions along with the α-posi-tion for the cross-linking to occur between the complementary base pairs of DNA, whichwill yield the carcinogenic activity of NNC. The above conception of bifunctional alkyla-tion can reduce the QSCAR of NNC to a reasonable structure-chemical reactivity relationshipunder the complex biological conditions, and is the successful extension of the Di-regiontheory to the carcinogenesis mechanism of the important NNC series. In the light of theabove viewpoint, for 153 NNCs including the nitrosamines and nitrosamides which havebeen tested reliably with animals, the correct discrimination ratio by quantitative patternrecognition according to carcinogenic activity indexes divided into 5 degrees comes up to ashigh as 97%.
文摘目的:研究胃萎方对信号转导及转录激活蛋白3(Signal Transducer and Activator of Transcription 3,STAT3)/核因子-κB(Nuclear Factor-κB,NF-κB)信号通路的调控作用,探讨胃萎方对胃癌前病变(Precancerous Lesion of Gastric Cancer,PLGC)的疗效及作用机制。方法:从70只雄性Wistar大鼠中随机选择20只作为空白组,其余50只为造模组。采用N-甲基-N’-硝基-N-亚硝基胍(MNNG)诱导GPL大鼠实验模型。14周后,对随机选择的造模组大鼠10只进行胃组织学分析,确认造模成功,造模组剩余40只大鼠随机分为模型组、胃萎方治疗组各20只。使用胃萎方干预后,观察大鼠体质量增长、胃黏膜组织结构变化,以及血清胃蛋白酶原(Pepsinogen,PG)Ⅰ,PGⅡ和胃泌素的浓度,并检测NF-κB p65和STAT3的基因及蛋白表达。结果:与空白组比较,模型组大鼠体质量增长缓慢,胃黏膜组织细胞异型增生明显,血清PGⅠ、胃泌素水平和PGⅠ/PGⅡ比值显著降低,胃黏膜NF-κB/STAT3信号通路被激活;与模型组比较,胃萎方治疗组大鼠整体情况改善,胃黏膜组织结构重塑、萎缩性胃黏膜和非典型腺上皮减少,PGⅠ/PGⅡ比值和胃泌素水平增加(P<0.01),NF-κB p65和STAT3的mRNA及蛋白的表达受到一定程度的抑制(P<0.05)。结论:胃萎方能够通过抑制NF-κB/STAT3信号通路逆转MNNG诱导的大鼠GPL,为胃萎方的临床应用提供了基础证据。
文摘Stomach carcinoma is still the leading cause of cancer death in China and the second one in the world. Its possible causes include: A) chemical factors such as intragastric formation of N-nitroso compounds (NOC) and high salt intake; B ) biological factors such as infection of Helicobacter pylori and biotoxins intake; and C ) nutritional factors such as deficiency of vitamin C, selenium, and other antioxidants. Nitrogenous precursors of NOC, e.g., alkylamines, alkylureas, alkylguanidines, and alkylamides, occur widely in nature and potential nitrosating agents, e.g., nitrite (NO2-) and NOx (the gaseous oxides of nitrogen ) are similarly widespread. Relationship between exposure to NOC and causes of human cancer was investigated extensively ten years ago. Results indicated that the exposures of NOC might contribute to the occurrences of malignancy in the upper digestive tracts including stomachs. It was also observed that both high salt intake and deficiency of some micronutrients enhanced NOC-induced carcinogenicity. Recent studies show that infection of H. pylori can lead to atrophic gastritis and achlorhydria, and promote endogenous formation of NOC indirectly[1] . Much attention has been paid to stomach cancer and NOC regarding the characterization of natural N-nitrosamides in human environment in the 1990s.
