Fragrant camphor tree is the city tree of Hangzhou which takes a large proportion of the ancient trees in Hangzhou City. Recently, with the free open of the attractions around the West Lake and the implementation of t...Fragrant camphor tree is the city tree of Hangzhou which takes a large proportion of the ancient trees in Hangzhou City. Recently, with the free open of the attractions around the West Lake and the implementation of the comprehensive pro- ject for protecting the West Lake, a part of ancient fragrant camphor trees are fac- ing problems such as altered living conditons. Some of them are showing a decline in growth vigor or even close to death, which will produce extremely negative influ- ences on the maintaining and sustainable development of the West Lake Scenic Area if without any timely measures for the rescue and rejuvenation of the trees. Therefore, strengthening the protection and management of ancient fragrant camphor trees at the West Lake Scenic Area and carrying out researches on the procedure for diagnosing the reasons for the growth recession of the ancient fragrant camphor trees at the West Lake Scenic Area are of great significance for the future protec- tion and rejuvenation of the ancient trees around the West Lake. The factors influ- encing the growth of ancient trees and indexes for judging the growth condition were listed and the reasons for the growth recession were systematically summa- rized in this paper. In addition, measures for the rejuvenation of the ancient fragrant camphor trees were also simply discussed.展开更多
Two dinuclear organotin complexes C8H14(CO2SnCy3)2(1)(Cy = cyclohexyl group) and C8H14[CO2Sn(CH2CMe2Ph)3]2(2) were synthesized by the reactions of camphoric acid with tricyclohexyltin hydroxide and bis[tri(...Two dinuclear organotin complexes C8H14(CO2SnCy3)2(1)(Cy = cyclohexyl group) and C8H14[CO2Sn(CH2CMe2Ph)3]2(2) were synthesized by the reactions of camphoric acid with tricyclohexyltin hydroxide and bis[tri(2-methyl-2-phenyl)propyltin] oxide under solvothermal conditions, and these complexes were characterized by infrared spectra, elemental analyses, and H NMR spectra. The crystal of 1 belongs to the monoclinic system, space group P21/c with a = 1.83478(19), b = 1.52707(18), c = 1.9849(2) nm, β = 122.515(7)°, Z = 4, V = 4.6896(9) nm^3, Dc = 1.324 g/cm^3, μ(MoKα) = 1.103 mm^-1, F(000) = 1952, R = 0.0697 and wR = 0.2040. In addition, thermal stability and quantum chemical calculation of 1 were also studied.展开更多
The dynamic changes in the malondialdehyde(MDA), superoxide dismutase(SOD), soluble sugar, proline, and soluble protein contents, as well as the relative electrolyte conductivity and the corresponding cold resista...The dynamic changes in the malondialdehyde(MDA), superoxide dismutase(SOD), soluble sugar, proline, and soluble protein contents, as well as the relative electrolyte conductivity and the corresponding cold resistance, of Cinnamomum bodinieri Level., C. camphora L., and C. caudiferum Kisterm were investigated during the winter months of October 2009 to April 2010. During the short period of temperature decline that lasted until mid-December, the changes in the relative electrolyte conductivity and MDA content with temperature were insignificant. In January, SOD activity continued to increase and then peaked as a result of rapid increases in soluble sugar, proline, soluble protein, as well as the inhibition of the relative electrolyte conductivity and decrease in MDA content. These physiological changes protected the camphor trees from cold damage during winter. From February to March, SOD activity and the soluble protein and proline contents increased with the increase in temperature. However, the relative electrolyte conductivity and MDA content decreased, indicating that the cell membrane damaged by low temperature was gradually being repaired. The cold dip in April led to slight increases in the relative electrolyte conductivity and MDA content. Using a fuzzy mathematics method, the cold resistance adaptability of the camphor trees was divided into three periods namely, the enhancement setting stage, the vigorous stage, and the reducing stage. The cold tolerance abilities were ranked as the following order: C. bodinieri Level〉C. camphora L.〉C. caudiferum Kisterm.展开更多
The non-edible camphor tree seed oil was extracted and catalyzed by immobilized lipase for biodiesel production. The oil yield from camphor tree seeds reached 35.2% of seed weight by twice microwave-assisted extractio...The non-edible camphor tree seed oil was extracted and catalyzed by immobilized lipase for biodiesel production. The oil yield from camphor tree seeds reached 35.2% of seed weight by twice microwave-assisted extractions. Gas chromatography showed that free fatty acid content in camphor tree seed oil was 1.88%, and the main fatty acids were capric acid(53.4%) and lauric acid(38.7%). With immobilized lipase Candida sp. 99–125as catalyst, several important factors for reaction conditions were examined through orthogonal experiments.The optimum conditions were obtained: water content and enzyme loading were both 15% with a molar ratio of 1:3.5(oil/ethanol), and the process of alcoholysis was in nine steps at 40 °C for 24 h, with agitation at170 r·min-1. As a result, the medium-chain biodiesel yield was 93.5%. The immobilized lipase was stable when it was used repeatedly for 210 h.展开更多
In this study,low-field nuclear magnetic resonance(LF-NMR)was used to collect the transverse relaxation signals of camphor seeds that had been dried at different temperatures and for different durations.The transverse...In this study,low-field nuclear magnetic resonance(LF-NMR)was used to collect the transverse relaxation signals of camphor seeds that had been dried at different temperatures and for different durations.The transverse relaxation time of the hydrogen nucleus was obtained by SIRT(Simultaneous Iterative Reconstruction Technique)inversion,and the correlation between the moisture content on dry basis and the amplitude of NMR signal of camphor seeds sampled at different drying stages was analyzed.The results showed that water existed in three main forms strongly bound water,weakly bound water and free water in camphor seeds.During the drying process,the peak position of strongly bound water remained unchanged,but the peak positions of weakly bound water and free water fluctuated.Drying rate increased with drying temperature increasing.In addition,there was a very significant linear relationship between the total NMR signal amplitude and moisture content on dry basis,and the correlation coefficient reached 0.984 4.展开更多
Hydrocarbon precursor such as methane has been widely used to grow graphene films and the methods of growing quality graphene films are dominated by thermal CVD (chemical vapor deposition) system. Graphene films gro...Hydrocarbon precursor such as methane has been widely used to grow graphene films and the methods of growing quality graphene films are dominated by thermal CVD (chemical vapor deposition) system. Graphene films grown by plasma process are generally highly defective which in turns degrade the quality of the films. Here, using a green precursor, camphor we demonstrate a simple and economical method to get high-quality graphene film on copper substrate by micro wave surface-wave plasma CVD at relatively low temperature 550℃. Graphene film grown using camphor shows superior quality than that of the film grown using methane. Results revealed that camphor precursor is a good alternative to hydrocarbon precursors for graphene research.展开更多
The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to ...The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to shorter wavelength when polyaniline was doped with CSAH in N methyl 2 pyrrolidione (NMP) solvent, while the red shift of polaron band was observed when it was in N, N dimethylformamide (DMF). It indicates that the influence of different processing solvents on the doping property of polyaniline is greatly different. N methyl 2 pyrrolidione is a good solvent for polyaniline, polyaniline chain is unfolded in it. The interaction of NMP with CSAH is so strong that the resulting product is apt to dedoping, while the solubility of polyaniline in DMF is relatively low and polyaniline chain is in partly folded state. Thus the doping reaction is kinetically disadvantageous but thermodynamically advantageous.展开更多
A novel coordination polymer, Mn(H_2O)(CA)(Phen)·H_2O(CA=camphoric acid, Phen=1,10-phenanthroline), was synthesized and its crystal structure was determined by single crystal X-ray diffraction. Six-coordinated {...A novel coordination polymer, Mn(H_2O)(CA)(Phen)·H_2O(CA=camphoric acid, Phen=1,10-phenanthroline), was synthesized and its crystal structure was determined by single crystal X-ray diffraction. Six-coordinated {Mn(Ⅱ)} atoms are linked with carboxyl groups from camphoric acid ligands to form infinite one-dimensional chains. These chains are packed by means of hydrogen bonding and π-π stacking, forming a three-dimensional structure. IR, thermogravimetric analysis and magnetic susceptibility data for Mn(H_2O)(CA)(Phen)·H_2O are given.展开更多
A chiral lanthanide metal-organic framework based on enantiopure camphoric acid (D-H2cam), [Nd3(D-cam)8(H2O)4Cl]n (1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemen...A chiral lanthanide metal-organic framework based on enantiopure camphoric acid (D-H2cam), [Nd3(D-cam)8(H2O)4Cl]n (1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows: orthorhombic system, space group P212121 with a = 13.8287(7), b = 14.0715(7), c = 25.7403(12) A^°, V = 5008.8(4) A^°3, Mr = 1333.08, Z = 4, F(000) = 2644, Dc = 1.768 g/cm^3, μ(MoKα) = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 (I 〉 2σ(I)). Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism (VCD) spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.展开更多
The asymmetric alkylations of chiral transition metal complexes derived from (+)-camphor and 2-aminomethyl-6-methylpyridine were examined under mild conditions.The formation of the complexes 2 is conductive to the enh...The asymmetric alkylations of chiral transition metal complexes derived from (+)-camphor and 2-aminomethyl-6-methylpyridine were examined under mild conditions.The formation of the complexes 2 is conductive to the enhancement of di- astereoselectivity in the alkylations at room temperature.展开更多
Camphor(C_(10)H_(16)O)is a white crystalline solid exist in enantiomeric form R and S camphor.It is a terpenoid obtained from turpentine oil.Synthetically it is synthesized by catalytic process as alpha pinene.Natural...Camphor(C_(10)H_(16)O)is a white crystalline solid exist in enantiomeric form R and S camphor.It is a terpenoid obtained from turpentine oil.Synthetically it is synthesized by catalytic process as alpha pinene.Naturally camphor is obtained by steam distillation of woods of Cinnamomum camphora tree,also known as Camphor tree,camphor laure and camphor wood.Camphor has many pharmacological properties.It acts as antiviral,anticancerous,antimicrobial,insecticidal,anticoccidial,anti-nociceptive and antitussive drug.In addition,it can be used as skin penetrating enhancer.Camphor gives a soothing and cooling effect,which helps to reduce pain.The reason behind its soothing effect is camphor act as a counter-irritant by activating heat sensitive transient receptor potential vanilloid subtype 1 and transient receptor potential vanilloid subtype 3 receptors and inhibits the transient receptor potential melastatin-subfamily member 8 receptor.As a result,these receptors provide a sensation of scalding heat and pain(nociception)and could be used to treat neuropathic pain associated with multiple sclerosis,chemotherapy,or amputation,as well as pain associated with the inflammatory response of damaged tissue such as in osteoarthritis.Camphor has a history of epidemics cure.During leishmaniosis(kala-azar)pandemic in 14th century,camphor was used as fumigant to control the spread of plague in European countries.In 19th century when cholera,small pox and influenza spreads,camphor was used as mothballs in Indian subcontinent as a(cough reliever)agent.During 18th century Russian influenza“flu pandemic”founder of Homeopathy Hahnemann in 1831,published his research work on camphor and suggested camphor as a“divine remedy”for influenza given in extremely small doses.In the same year,several companies launched to sell menthol rub as natural rub ointment consisting camphor as prevention measures for spread of influenza.As the recent epidemic of COVID-19 arises,prevention and control of spread of disease is an alarming issue.This article covered the glimpse of uses and importance of camphor in the history of epidemic cure.展开更多
UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing g...UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.展开更多
Syntheses of (1R,2S,3R,4S)-1,7,7-trimethyl-2-pyridin-2-ylmethylbicyclo[2.2.1]-heptane-2,3-diol (7), (1R,2S,3R,4S)-1,7,7-trimethyl-2-[(6-methyl)-pyridin-2-ylmethyl-bicyclo-[2.2.1]heptane-2,3-diol (13), and (1R,2S,2’R,...Syntheses of (1R,2S,3R,4S)-1,7,7-trimethyl-2-pyridin-2-ylmethylbicyclo[2.2.1]-heptane-2,3-diol (7), (1R,2S,3R,4S)-1,7,7-trimethyl-2-[(6-methyl)-pyridin-2-ylmethyl-bicyclo-[2.2.1]heptane-2,3-diol (13), and (1R,2S,2’R,4R)-1,7,7-trimethyl-2-piperidin-2-ylmethyl-bicyclo[2.2.1]heptan-2-ol (19b) from commercially available (d)-camphor (1) are described. Key steps of the syntheses involved substrate-controlled diastereoselective alkylation and platinum oxide-catalyzed hydrogenation reactions. These compounds, and other intermediate amino alcohols in their syntheses, were successfully utilized as ligands in enantioselective diethyl zinc (Et2Zn) addition to benzaldehyde with moderate enantioselectivity.展开更多
A new polymer [Zn2(cam)2(bpmp)]n 1 (H2cam = D-(+)-camphoric acid, bpmp = bis(4-pyridylmethyl)piperazine) was synthesized under hydrothermal conditions. The compound crystallizes in the monoclinic system, sp...A new polymer [Zn2(cam)2(bpmp)]n 1 (H2cam = D-(+)-camphoric acid, bpmp = bis(4-pyridylmethyl)piperazine) was synthesized under hydrothermal conditions. The compound crystallizes in the monoclinic system, space group P21/n with a = 12.305(9), b = 12.945(9), c = 13.619(10) A, β = 116.833(8)°, V= 1936(2)A3, Z = 4, Mr = 397.76, Dc= 1.365 Mg/m3,μ = 1.292 mm-1, F(000) = 832, the final R = 0.0578 and wR = 0.1678 for 2838 observed reflections with I 〉 2σ(I). The compound presents a three-dimensional (3D) network extended by homochiral 2D layer and bpmp ligands. From the topology point of view, the structure could be described as a 3D 6-connected mab net with (44.610.8) topology. In addition, infrared spectroscopy, elemental analyses, thermogravimetric analysis and powder X-ray diffraction properties of 1 are also investigated.展开更多
基金Supported by the Key Project of Hangzhou Bureau for Gardens and Cultural Relics(2009-003)~~
文摘Fragrant camphor tree is the city tree of Hangzhou which takes a large proportion of the ancient trees in Hangzhou City. Recently, with the free open of the attractions around the West Lake and the implementation of the comprehensive pro- ject for protecting the West Lake, a part of ancient fragrant camphor trees are fac- ing problems such as altered living conditons. Some of them are showing a decline in growth vigor or even close to death, which will produce extremely negative influ- ences on the maintaining and sustainable development of the West Lake Scenic Area if without any timely measures for the rescue and rejuvenation of the trees. Therefore, strengthening the protection and management of ancient fragrant camphor trees at the West Lake Scenic Area and carrying out researches on the procedure for diagnosing the reasons for the growth recession of the ancient fragrant camphor trees at the West Lake Scenic Area are of great significance for the future protec- tion and rejuvenation of the ancient trees around the West Lake. The factors influ- encing the growth of ancient trees and indexes for judging the growth condition were listed and the reasons for the growth recession were systematically summa- rized in this paper. In addition, measures for the rejuvenation of the ancient fragrant camphor trees were also simply discussed.
基金Supported by Natural Science Foundation of Hunan Province(No.13JJ3112)Scientific & Technological Projects of Hunan Province(No.2013TZ2025,2014NK3086)+3 种基金Open Foundation of Innovation Platform of Hunan Provincial University(No.13K105,14K014)Scientific & Technological Projects of Hengyang City(No.2012KJ30)Cultivation projects Based on Collaborative Innovation Center of Hengyang Normal University(No.12XT02)the Youth Backbone Teacher Training Program of Hengyang Normal University(2012)
文摘Two dinuclear organotin complexes C8H14(CO2SnCy3)2(1)(Cy = cyclohexyl group) and C8H14[CO2Sn(CH2CMe2Ph)3]2(2) were synthesized by the reactions of camphoric acid with tricyclohexyltin hydroxide and bis[tri(2-methyl-2-phenyl)propyltin] oxide under solvothermal conditions, and these complexes were characterized by infrared spectra, elemental analyses, and H NMR spectra. The crystal of 1 belongs to the monoclinic system, space group P21/c with a = 1.83478(19), b = 1.52707(18), c = 1.9849(2) nm, β = 122.515(7)°, Z = 4, V = 4.6896(9) nm^3, Dc = 1.324 g/cm^3, μ(MoKα) = 1.103 mm^-1, F(000) = 1952, R = 0.0697 and wR = 0.2040. In addition, thermal stability and quantum chemical calculation of 1 were also studied.
基金Supported by Youth Science Foundation from Henan University of Science and Technology(2013)
文摘The dynamic changes in the malondialdehyde(MDA), superoxide dismutase(SOD), soluble sugar, proline, and soluble protein contents, as well as the relative electrolyte conductivity and the corresponding cold resistance, of Cinnamomum bodinieri Level., C. camphora L., and C. caudiferum Kisterm were investigated during the winter months of October 2009 to April 2010. During the short period of temperature decline that lasted until mid-December, the changes in the relative electrolyte conductivity and MDA content with temperature were insignificant. In January, SOD activity continued to increase and then peaked as a result of rapid increases in soluble sugar, proline, soluble protein, as well as the inhibition of the relative electrolyte conductivity and decrease in MDA content. These physiological changes protected the camphor trees from cold damage during winter. From February to March, SOD activity and the soluble protein and proline contents increased with the increase in temperature. However, the relative electrolyte conductivity and MDA content decreased, indicating that the cell membrane damaged by low temperature was gradually being repaired. The cold dip in April led to slight increases in the relative electrolyte conductivity and MDA content. Using a fuzzy mathematics method, the cold resistance adaptability of the camphor trees was divided into three periods namely, the enhancement setting stage, the vigorous stage, and the reducing stage. The cold tolerance abilities were ranked as the following order: C. bodinieri Level〉C. camphora L.〉C. caudiferum Kisterm.
基金Supported by Key Projects in the National Science & Technology Pillar Program during the 12th Five-year Plan Period(2011BAD22B04)the National Basic Research Program of China(973 program)(2011CB710800,2011CB200905,2009CB724703)+2 种基金the National Natural Science Foundation of China(21076017)the National High-Tech R & D Program of China(863 Program)(2012AA021404,2012AA021402)the Fundamental Research Funds for the Central Universities(ZY1331)
文摘The non-edible camphor tree seed oil was extracted and catalyzed by immobilized lipase for biodiesel production. The oil yield from camphor tree seeds reached 35.2% of seed weight by twice microwave-assisted extractions. Gas chromatography showed that free fatty acid content in camphor tree seed oil was 1.88%, and the main fatty acids were capric acid(53.4%) and lauric acid(38.7%). With immobilized lipase Candida sp. 99–125as catalyst, several important factors for reaction conditions were examined through orthogonal experiments.The optimum conditions were obtained: water content and enzyme loading were both 15% with a molar ratio of 1:3.5(oil/ethanol), and the process of alcoholysis was in nine steps at 40 °C for 24 h, with agitation at170 r·min-1. As a result, the medium-chain biodiesel yield was 93.5%. The immobilized lipase was stable when it was used repeatedly for 210 h.
文摘In this study,low-field nuclear magnetic resonance(LF-NMR)was used to collect the transverse relaxation signals of camphor seeds that had been dried at different temperatures and for different durations.The transverse relaxation time of the hydrogen nucleus was obtained by SIRT(Simultaneous Iterative Reconstruction Technique)inversion,and the correlation between the moisture content on dry basis and the amplitude of NMR signal of camphor seeds sampled at different drying stages was analyzed.The results showed that water existed in three main forms strongly bound water,weakly bound water and free water in camphor seeds.During the drying process,the peak position of strongly bound water remained unchanged,but the peak positions of weakly bound water and free water fluctuated.Drying rate increased with drying temperature increasing.In addition,there was a very significant linear relationship between the total NMR signal amplitude and moisture content on dry basis,and the correlation coefficient reached 0.984 4.
文摘Hydrocarbon precursor such as methane has been widely used to grow graphene films and the methods of growing quality graphene films are dominated by thermal CVD (chemical vapor deposition) system. Graphene films grown by plasma process are generally highly defective which in turns degrade the quality of the films. Here, using a green precursor, camphor we demonstrate a simple and economical method to get high-quality graphene film on copper substrate by micro wave surface-wave plasma CVD at relatively low temperature 550℃. Graphene film grown using camphor shows superior quality than that of the film grown using methane. Results revealed that camphor precursor is a good alternative to hydrocarbon precursors for graphene research.
文摘The doping reaction of polyaniline with camphor sulfonic acid (CSAH) in different organic solvents was studied by UV Vis spectroscopy. The experimental results show that the polaron band of the species was shifted to shorter wavelength when polyaniline was doped with CSAH in N methyl 2 pyrrolidione (NMP) solvent, while the red shift of polaron band was observed when it was in N, N dimethylformamide (DMF). It indicates that the influence of different processing solvents on the doping property of polyaniline is greatly different. N methyl 2 pyrrolidione is a good solvent for polyaniline, polyaniline chain is unfolded in it. The interaction of NMP with CSAH is so strong that the resulting product is apt to dedoping, while the solubility of polyaniline in DMF is relatively low and polyaniline chain is in partly folded state. Thus the doping reaction is kinetically disadvantageous but thermodynamically advantageous.
文摘A novel coordination polymer, Mn(H_2O)(CA)(Phen)·H_2O(CA=camphoric acid, Phen=1,10-phenanthroline), was synthesized and its crystal structure was determined by single crystal X-ray diffraction. Six-coordinated {Mn(Ⅱ)} atoms are linked with carboxyl groups from camphoric acid ligands to form infinite one-dimensional chains. These chains are packed by means of hydrogen bonding and π-π stacking, forming a three-dimensional structure. IR, thermogravimetric analysis and magnetic susceptibility data for Mn(H_2O)(CA)(Phen)·H_2O are given.
基金supported by National Natural Science Foundation of China(21401147)Basic Research Program of Natural Science from Shaanxi Provincial Government(2015JQ2032)+2 种基金Scientific Research Program from Education Department of Shaanxi Provincial Government(2013JK0654)Opening Foundation from State Key Laboratory of Coordination Chemistry in Nanjing University(201219)the Program for Distinguished Young Scholars of Xi’an Polytechnic University(201403)
文摘A chiral lanthanide metal-organic framework based on enantiopure camphoric acid (D-H2cam), [Nd3(D-cam)8(H2O)4Cl]n (1), has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows: orthorhombic system, space group P212121 with a = 13.8287(7), b = 14.0715(7), c = 25.7403(12) A^°, V = 5008.8(4) A^°3, Mr = 1333.08, Z = 4, F(000) = 2644, Dc = 1.768 g/cm^3, μ(MoKα) = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 (I 〉 2σ(I)). Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism (VCD) spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.
基金This work was supported by the National Natural Science Foundation of China.
文摘The asymmetric alkylations of chiral transition metal complexes derived from (+)-camphor and 2-aminomethyl-6-methylpyridine were examined under mild conditions.The formation of the complexes 2 is conductive to the enhancement of di- astereoselectivity in the alkylations at room temperature.
文摘Camphor(C_(10)H_(16)O)is a white crystalline solid exist in enantiomeric form R and S camphor.It is a terpenoid obtained from turpentine oil.Synthetically it is synthesized by catalytic process as alpha pinene.Naturally camphor is obtained by steam distillation of woods of Cinnamomum camphora tree,also known as Camphor tree,camphor laure and camphor wood.Camphor has many pharmacological properties.It acts as antiviral,anticancerous,antimicrobial,insecticidal,anticoccidial,anti-nociceptive and antitussive drug.In addition,it can be used as skin penetrating enhancer.Camphor gives a soothing and cooling effect,which helps to reduce pain.The reason behind its soothing effect is camphor act as a counter-irritant by activating heat sensitive transient receptor potential vanilloid subtype 1 and transient receptor potential vanilloid subtype 3 receptors and inhibits the transient receptor potential melastatin-subfamily member 8 receptor.As a result,these receptors provide a sensation of scalding heat and pain(nociception)and could be used to treat neuropathic pain associated with multiple sclerosis,chemotherapy,or amputation,as well as pain associated with the inflammatory response of damaged tissue such as in osteoarthritis.Camphor has a history of epidemics cure.During leishmaniosis(kala-azar)pandemic in 14th century,camphor was used as fumigant to control the spread of plague in European countries.In 19th century when cholera,small pox and influenza spreads,camphor was used as mothballs in Indian subcontinent as a(cough reliever)agent.During 18th century Russian influenza“flu pandemic”founder of Homeopathy Hahnemann in 1831,published his research work on camphor and suggested camphor as a“divine remedy”for influenza given in extremely small doses.In the same year,several companies launched to sell menthol rub as natural rub ointment consisting camphor as prevention measures for spread of influenza.As the recent epidemic of COVID-19 arises,prevention and control of spread of disease is an alarming issue.This article covered the glimpse of uses and importance of camphor in the history of epidemic cure.
基金supported by the National Natural Science Foundation of China(21172161)
文摘UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.
文摘Syntheses of (1R,2S,3R,4S)-1,7,7-trimethyl-2-pyridin-2-ylmethylbicyclo[2.2.1]-heptane-2,3-diol (7), (1R,2S,3R,4S)-1,7,7-trimethyl-2-[(6-methyl)-pyridin-2-ylmethyl-bicyclo-[2.2.1]heptane-2,3-diol (13), and (1R,2S,2’R,4R)-1,7,7-trimethyl-2-piperidin-2-ylmethyl-bicyclo[2.2.1]heptan-2-ol (19b) from commercially available (d)-camphor (1) are described. Key steps of the syntheses involved substrate-controlled diastereoselective alkylation and platinum oxide-catalyzed hydrogenation reactions. These compounds, and other intermediate amino alcohols in their syntheses, were successfully utilized as ligands in enantioselective diethyl zinc (Et2Zn) addition to benzaldehyde with moderate enantioselectivity.
基金Supported by the National Natural Science Foundation of China(No.21076063)Foundation of Henan Educational Committee(No.13A150244)
文摘A new polymer [Zn2(cam)2(bpmp)]n 1 (H2cam = D-(+)-camphoric acid, bpmp = bis(4-pyridylmethyl)piperazine) was synthesized under hydrothermal conditions. The compound crystallizes in the monoclinic system, space group P21/n with a = 12.305(9), b = 12.945(9), c = 13.619(10) A, β = 116.833(8)°, V= 1936(2)A3, Z = 4, Mr = 397.76, Dc= 1.365 Mg/m3,μ = 1.292 mm-1, F(000) = 832, the final R = 0.0578 and wR = 0.1678 for 2838 observed reflections with I 〉 2σ(I). The compound presents a three-dimensional (3D) network extended by homochiral 2D layer and bpmp ligands. From the topology point of view, the structure could be described as a 3D 6-connected mab net with (44.610.8) topology. In addition, infrared spectroscopy, elemental analyses, thermogravimetric analysis and powder X-ray diffraction properties of 1 are also investigated.