Synthesis of Chiral 3-Acylcamphors

3-Acylcamphors were synthesized in moderate yields by the condensation of camphorwith esters using sodium hydride as a base.

Cinnamomum camphora: a long history for epidemics control

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.

土壤干旱胁迫对樟树(Cinnamomum camphora (L.) Presl)苗木水力结构特征的影响

植物水力结构特征通常用导水率(Kh)、比导率(Ks)、叶比导率(LSC)、胡伯尔值(Hv)等参数来表征。设置了3种土壤干旱胁迫强度和对照共4种处理,每一处理5个重复,采用"冲洗法"对喀斯特地区造林树种两年生樟树(Cinnamomum camphora(L.)Presl)苗木的水力结构相关参数进行测定。结果表明:樟树苗木在正常水分和不同强度土壤干旱胁迫条件下,其茎段导水率、比导率、叶比导率、胡伯尔值均与茎段直径呈正相关关系,并可以用不同类型函数进行拟合。随着干旱胁迫强度的加剧,不同处理的导水率、比导率、叶比导率降低,胡伯尔值在不同处理间的差异不显著。这说明较粗的茎段,其单位横截面积的导管投入与使用效率明显高于较细茎段,且供给末端叶片水分所需要的压力梯度小于较细茎段。结果为进一步探讨土壤干旱对樟树苗木水力结构作用机理及在石漠化山地造林的适应性提供理论依据。

Physiological Changes and Cold Tolerance of Three Camphor Species During Natural Winter Temperature Fluctuations

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.

Analysis of Internal Moisture Change of Camphor Seeds during Drying by Low-Field NMR

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.

An 8-Connected Chiral Lanthanide Metal-organic Framework Constructed from Naturally Camphoric Acid:Crystal Structure,Vibrational Circular Dichroism Spectroscopy and Second-order Nonlinear Optical Effect

A chiral lanthanide metal-organic framework based on enantiopure camphoric acid(D-H_2cam), [Nd_3(D-cam)8(H_2O)_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) ?, V = 5008.8(4) ?3, M_r = 1333.08, Z = 4, F(000) = 2644, D_c = 1.768 g/cm3, μ(MoKα) = 3.189 mm-1, the final R = 0.0351 and w R = 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.

UV- VIS SPECTRA OF POLYANILINE DOPED WITH CAMPHOR SULFONIC ACID IN DIFFERENT ORGANIC SOLVENTS

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.

THE ASYMMETRIC ALKYLATIONS OF CHIRAL TRANSITION METAL COMPLEXES OF(+)—CAMPHOR IMINE

The asymmetric alkylations of chiral transition metal complexes derived from(+)-camphor and 2-aminomethyl-6-methylpyridine were examined under mildconditions.The formation of the complexes 2 is conductive to the enhancement of di-astereoselectivity in the alkylations at room temperature.

Chiral Camphor-Based 1,3- and 1,4-Amino Alcohols and Aminodiols as Ligands for Diethylzinc Addition to Aldehydes

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.

龙脑樟(Cinnamomum camphora)组培快繁与苗木工厂化生产技术研究

选取龙脑含量高的优良单株,以其树干基部的幼嫩萌条为外植体开展龙脑樟组培快繁技术研究。结果表明:以改良MS+BA2.0 mg.L-1+NAA 0.1 mg.L-1为芽诱导培养基,诱导率为93%;最佳增殖培养基为改良MS+BA 2.0 mg.L-1+NAA 0.05 mg.L-1,增殖系数为5.57,生长周期为30 d;适宜的增殖培养条件为温度25℃,光照强度3 000 lx,光照时间11 h,不定芽长势良好;最佳生根培养基为1/2改良MS+IBA 0.5 mg.L-1+IAA 0.4 mg.L-1+蔗糖20 g.L-1,生根率可达97.3%,生根条数为3～5条,生根时间为12 d;以草炭+珍珠岩(3∶1)为移栽基质,成活率可达86.2%。通过试验总结出一套组培快繁技术体系,可应用于龙脑樟组培苗工厂化生产。

Solvothermal Syntheses, Crystal Structures, Thermal Stability and Quantum Chemistry of Dinuclear Trialkyltin Complexes Constructed by Camphoric Acid

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) nm3, Dc = 1.324 g/cm3, 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.

UV-Vis Spectrum and the Third-order Nonlinear Optical Properties of the Chiral Camphorderived β-diketonate Platinum Complexes

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.

Synthesis, Structure and Characterization of Manganese(Ⅱ) Coordination Polymer with Camphoric Acid and 1,10-Phenanthroline

A novel coordination polymer, Mn（H2O）（CA）（Phen）·H2O（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（H2O）（CA）（Phen）·H2O are given.

Construction of One New 3D Zinc-organic Framework Based on D-(+)-camphoric Acid and Bis(4-pyridylmethyl)piperazine

A new polymer[Zn2(cam)2(bpmp)]n1(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),β=116.833(8)°,V=1936(2)3,Z=4,Mr=397.76,Dc=1.365 Mg/m3,μ=1.292mm-1,F(000)=832,the final R=0.0578 and wR=0.1678 for 2838 observed reflections with I>2(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 3D6-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.

Gold Determination by Electrothermal Atomic Absorption Spectrometry After Preconcentration Using Natural Deep Eutectic Solvent Based on Menthol and Camphor

A novel analytical procedure for the determination of gold by electrothermal atomic absorption spectrometry combined with selective liquid-liquid extraction by natural deep eutectic solvents(NADESs)is presented.The extraction ability of the NADESs prepared using menthol,thymol and camphor toward gold in hydrochloric acid solutions was studied.The extraction efficiency was improved by optimizing the parameters including the composition of the NADES s,the volume ratio of organic and aqueous phases,kinetics,and acidity of the solution.Quantitative determination of gold was carried out by electrothermal atomic absorption spectrometry directly in the NADES s phase dissolved in isopropyl alcohol.The extraction recovery of gold from 1 mol/L HCl with the NADESs based on menthol and camphor mixed in a molar ratio 1:1 was 99.7%at an enrichment factor of 100.The limits of detection and quantification of the proposed procedure were 1μg/L and 3.3μg/L,respectively,with a relative standard deviation of less than 5%.The developed procedure was applied for determination of gold in the certified reference material of ore,environmental and waste waters.

樟树5种化学型精油组成及其胰脂肪酶抑制活性研究

采用GC和GC-MS方法分析确定了樟树5种精油化学成分组成,进一步研究了5种不同类型精油的胰脂肪酶抑制活性。结果表明:5种精油主成分分别为:芳樟醇(91.98%)、樟脑(81.25%)、龙脑(91.88%)、反式-橙花叔醇(52.63%)和桉叶油素(57.73%)。精油的胰脂肪酶抑制活性顺序为:反式-橙花叔醇型>桉叶油素型>芳樟醇型>樟脑型>龙脑型。其中反式-橙花叔醇型精油IC50为(20.02±3.27)mg/mL,当其精油浓度为100 mg/mL时,胰脂肪酶抑制率达90.17%±1.56%。

基于热减量法2/1樟发射药安全贮存寿命预估

目的 预估2/1樟发射药的安全贮存寿命,建立一种基于加速热减量试验,利用热减量曲线和贝瑟洛特(Berthelot)方程预估其安全贮存寿命的方法。方法 首先对2/1樟发射药分别进行85、95、105、115℃下的加速热减量试验,获得样品在各个温度下不同加速时间的热减量数据。然后基于热减量曲线,得到2/1樟发射药在各个温度下的延滞期。最后利用各个温度下的半延滞期,根据Berthelot方程拟合得到2/1樟发射药安全贮存寿命预估模型。结果 根据其安全贮存寿命预估模型计算得到2/1樟发射药在30℃下的安全贮存寿命约为50.9 a。结论 预测结果与文献值接近,且试验时间比文献减少了近1/2,验证了该方法的有效性,可为2/1樟发射药或其他发射药的安全贮存寿命预估提供一种可行的技术途径。

Cyclometalated platinum(Ⅱ) complexes with sterically bulky camphor-derived groups as β-diketonate ancillary ligand:a new route to efficiently reducing π-π interactions and Pt-Pt interactions

A new series of mono-cyclometalated square planar platinum(Ⅱ) complexes have been synthesized and the single-crystal X-ray structures of complex 1 and 2 have been determined.The complexes have the general formula ppyPt(O^O),where ppy is 2-phenylpyridyl,and O^O is β-diketonate ancillary ligands with the acyl substituent group in position 3 of(D)-(+)-camphor.Although,like the many Pt(Ⅱ) complexes with square-planar geometry,these complexes have plane stacking modes in crystal structure,the sterically bulky camphor-derived groups compel extensive slipping of the molecular stacking planes,resulting in the negligible overlapping of the aromatic ring fragments between molecules and the considerable Pt-Pt distance.The resolved spectra and a little shifted emission in solid state of complexes show that there is significant reduction of π-π interactions and Pt-Pt interactions,and suggest these complexes may be good candidates for doped phosphorescent organic light emitting diodes(PhOLEDs) and even for nondoped PhOLEDs.