High-energy-density(HED)fuel(e.g.widely used JP-10 and RJ-4),featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combu...High-energy-density(HED)fuel(e.g.widely used JP-10 and RJ-4),featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combustion heat can provide more propulsion energy.To reduce the reliance on petroleum source,it is highly desirable to develop renewable alternatives for the production of strained polycyclic HED fuel,but which remains a big challenge because of the inaccessibility caused by the high strain,We herein demonstrate a three-step catalytic route towards highly strained C_(17)and C_(18)spirofuel with biomass feedstocks.The process includes catalytic aldol condensation of renewable cyclohexanone/cyclopentanone with benzaldehyde,catalytic spiro Diels-Alder(D-A)reaction of aldol adduct with isoprene,and catalytic hydrodeoxygenation.The key spiro D-A reaction is enabled by the catalysis of heterogeneous Lewis acidic ionic liquid.The chloroaluminate IL,formed by benign urea and AICl3,exhibits good catalytic performance and reusability for this step.An eventual hydrodeoxygenation(HDO)over Pd/C and H-Y produces strained tricyclic spirofuel with density>0.93 g/mL,combustion heat>41 MJ/L and freezing point<-40℃,which are better than the properties of tactical fuel RJ-4.Therefore,it is anticipated that the as-prepared renewable fuels have the potential to replace traditional petroleum-derived HED fuels.展开更多
Two novel spiro compounds,3-benzylidene-1,5-dioxaspiro[5.5]undecane-2,4-dione 1 and 3-（2-fluorobenzylidene）-1,5-dioxaspiro[5.5]undecane-2,4-dione 2,have been synthesized and characterized by X-ray single-crystal dif...Two novel spiro compounds,3-benzylidene-1,5-dioxaspiro[5.5]undecane-2,4-dione 1 and 3-（2-fluorobenzylidene）-1,5-dioxaspiro[5.5]undecane-2,4-dione 2,have been synthesized and characterized by X-ray single-crystal diffraction,IR and elemental analysis.Compound 1 belongs to the monoclinic system,space group P21/n with a=12.326（3）,b=5.6420（11）,c=20.089（4）,β= 101.79（3）o,C16H16O4,Mr= 272.29,V=1367.7（5）3,Z=4,Dc=1.322g/cm3,F（000）=576,μ（MoKa）=0.095 mm-1,the final R=0.0420 and wR=0.1159.Compound 2 is of monoclinic system,space group P21/n with a=12.283（3）,b=5.6367（11）,c=20.055（4）,β=102.00（3）o,C16H15FO4,Mr=290.28,V=1358.2（5）3,Z=4,Dc=1.420 g/cm3,F（000）=608,μ（MoKa）=0.110 mm-1,the final R=0.0353 and wR=0.0860.展开更多
Spiro heterocycles frequently occur in bioactive molecules. In the pursuit of neonicotinoids with spiro hererocycles, three types of novel neonicotinoids with spirobenzofuranone, spirooxindole or spiroacenaphythylenon...Spiro heterocycles frequently occur in bioactive molecules. In the pursuit of neonicotinoids with spiro hererocycles, three types of novel neonicotinoids with spirobenzofuranone, spirooxindole or spiroacenaphythylenone framework were designed and synthesized. Insecticidal evaluation showed that some of spirobenzofuranone containing neonicotinoids exhibited moderate activity against cowpea aphid, armyworm or brown planthopper.展开更多
The photochromic spiropyrans and spirooxazine having a succinimidyl ester or isothiocyanate pendant group can form covalent products with transaminated DNA. The absorption spectra and solid reflection spectra of modi...The photochromic spiropyrans and spirooxazine having a succinimidyl ester or isothiocyanate pendant group can form covalent products with transaminated DNA. The absorption spectra and solid reflection spectra of modified DNA with these photochromic spiro compounds were investigated.展开更多
A novel class of chiral spiro-fused bisoxazoline ligands possessing a deep chiral pocket was prepared.The developed ligands have been employed in the nickel-catalyzed highly enantioselective Michael-type Friedel-Craft...A novel class of chiral spiro-fused bisoxazoline ligands possessing a deep chiral pocket was prepared.The developed ligands have been employed in the nickel-catalyzed highly enantioselective Michael-type Friedel-Crafts reaction, affording the products bearing a trifluoromethylated all-carbon quaternary stereocenter with moderate to excellent yields(up to 99%) and good to excellent enantioselectivies(up to> 99.9% ee). Moreover, a proposed model of chiral pocket revealed that the attack of indole from the Re-face of β-CF_(3)-β-disubstituted nitroalkene was favorable.展开更多
A series of photo active azido analogues have been synthesized and their photochromic properties have also been investigated by UV-Vis spectrum. It will be used for the rapid and reliable preparation of large amounts ...A series of photo active azido analogues have been synthesized and their photochromic properties have also been investigated by UV-Vis spectrum. It will be used for the rapid and reliable preparation of large amounts of stable, non-radioactive labeled DNA and RNA hybridization probes. And it is supposed to be easily detected for its photochromic properties.展开更多
Novel spiro[dibenzo[a,i]xanthene-14,3＇-indoline]-2＇,8,13-triones were prepared by the three-component reaction ofβ-naphthol, isatins,and 2-hydroxy-1,4-naphoquinone in the presence of a catalytic amount of H_4SiW_...Novel spiro[dibenzo[a,i]xanthene-14,3＇-indoline]-2＇,8,13-triones were prepared by the three-component reaction ofβ-naphthol, isatins,and 2-hydroxy-1,4-naphoquinone in the presence of a catalytic amount of H_4SiW_（12）O_（40）.This protocol provides a simple one-step procedure with the advantages of easy work-up,mild reaction conditions and environmentally benign.展开更多
We investigated the bio-distributions of [125 I]Spiro-I formulated in sterically stabilized liposomes （SSL） or targeted liposomes （SSTL） in mice,especially their brain uptake.The [125 I]Spiro-I liposomes were prep...We investigated the bio-distributions of [125 I]Spiro-I formulated in sterically stabilized liposomes （SSL） or targeted liposomes （SSTL） in mice,especially their brain uptake.The [125 I]Spiro-I liposomes were prepared by film-ultrasound dispersion method.Cereport （RMP-7） was covalently conjugated with DSPE-PEG,which was attached to the surface of SSL to form SSTL.The encapsulation efficiencies （ee%） of [125 I]Spiro-I-SSL and [125 I]Spiro-I-SSTL were 97.47%±4.01% and 93.02%±2.98%,respectively.The average particle sizes were （66.47±0.76） nm and （71.40±0.45） nm,respectively.After intravenous administration,[125 I]Spiro-I was quickly eliminated from blood.SSL could prolong the retention time of [125 I]Spiro-I in blood and SSTL improved its brain uptake.The AUC of [125 I]Spiro-I-SSTL in brain was increased by 1.52 times as compared to [125 I]Spiro-I,indicating that SSTL could be used for the formulation of [125 I]Spiro-I for the imaging of central nervous system （CNS）.展开更多
The BF_3OEt_2 catalyzed one-pot 1,3-dipolar cycloaddition reaction of benzylamines,isatins and dimethyl acetylenedicarboxylate in dry methylene dichloride afforded the functionalized dihydrospiro[indoline-3,2＇-pyrrol...The BF_3OEt_2 catalyzed one-pot 1,3-dipolar cycloaddition reaction of benzylamines,isatins and dimethyl acetylenedicarboxylate in dry methylene dichloride afforded the functionalized dihydrospiro[indoline-3,2＇-pyrroles]in moderate to good yields and with high diastereoselectivity.The reaction was accomplished by the tandem 1,3-dioplar cycloaddition of in situ generated azomethine ylide with acetylenedicarboxylate and the nucleophilic addition of pyrrole ring to second molecular acetylenedicarboxylate.展开更多
A rapid and efficient, one pot synthesis of spirooxindole derivatives has been attempted by three- component reaction of isatin, malononitrile and carbonyl compound possessing a reactive c^-methylene group by using ta...A rapid and efficient, one pot synthesis of spirooxindole derivatives has been attempted by three- component reaction of isatin, malononitrile and carbonyl compound possessing a reactive c^-methylene group by using task specific ionic liquid, 1-butyl-3-methyl imidazolium hydroxide [bmim]OH as a catalyst. The important features of this methodology are straight forward route in short reaction time at room temperature and avoid any hazardous organic solvent, toxic catalyst, tedious purification step. Interestingly, this protocol is not only limited to mono-systems but also to the synthesis of newer bis- spirooxindole system. The separation of the product and reusability of the catalyst are easy with excellent yield. The [bmim]OH catalyst system could be reused up to five recycles without appreciable loss of activity.展开更多
X2Si=Ge： （X = H, Me, F, CI, Br, Ph, Ar...） is a new species. Its cycloaddition reaction is a new area for the study of germylene chemistry. The mechanism of cycloaddition reaction between singlet state Me2Si=Ge： a...X2Si=Ge： （X = H, Me, F, CI, Br, Ph, Ar...） is a new species. Its cycloaddition reaction is a new area for the study of germylene chemistry. The mechanism of cycloaddition reaction between singlet state Me2Si=Ge： and formaldehyde has been investigated with the CCSD（T）//MP2/cc-pvtz method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rule presented is that the two reactants first form a four-membered Si-heterocyclic ring germylene through the [2＋2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge： atom in the four-membered Si-heterocyclic ring germylene and the π orbital of formaldehyde form a π→p donor-acceptor bond, the four-membered Si-heterocyclic ring germylene further combines with formaldehyde to form an intermediate. Because the Ge atom in the intermediate undergoes sp^3 hybridization after transition state, then the intermediate isomerizes to a spiro-Ge-heterocyclic ring compound involving Si via a transition state. The research result indicates the laws of cycloaddition reaction between HzSi=Ge： and formaldehyde. It has important reference value for the cycloaddition reaction between X2Si=Ge： （X = H, Me, F, CI, Br, Ph, Ar…） and asymmetric to-bonded compounds, which is significant for the synthesis of small-ring and spiro-Ge-heterocyclic compounds involving Si. The study extends research area and enriches the research content of germylene chemistry.展开更多
A green,convenient,high yielding and one-pot procedure for the synthesis of novel spiro[benzo[α]pyrano[2,3-c]phenazine]derivatives by domino multi-component condensation reaction between 2-hydroxynaphthalene-l,4-dion...A green,convenient,high yielding and one-pot procedure for the synthesis of novel spiro[benzo[α]pyrano[2,3-c]phenazine]derivatives by domino multi-component condensation reaction between 2-hydroxynaphthalene-l,4-dione,benzene-l,2-diamines,ninhydrine,and malononitrile in the presence of a catalytic amount of 1,3-dimethyl-7H-purine-2,6-dione（theophylline） as an expedient,eco-friendly and reusable solid base catalyst under thermal,microwave irradiation and solvent-free conditions.This procedure has also been applied successfully for the synthesis of benzo[α]pyrano[2,3-c]phenazines.展开更多
Chiral spirocyclic compounds have attracted the attention of scholars and scientists owing to their potential applications in the pharmaceutical industry as either active pharmaceutical ingredients, catalysts in synth...Chiral spirocyclic compounds have attracted the attention of scholars and scientists owing to their potential applications in the pharmaceutical industry as either active pharmaceutical ingredients, catalysts in synthesizing active enantiomers, or as surface modifiers on silica particles to resolve entantiomers. In this study, five spiro compounds of 3,9-diphenyl-2,4,8,10-tetraoxaspiro[5.5]-undecane（1）, 3,9-（4-methoxyphenyl）-2,4,8,10-tetraoxaspiro [5.5] -undecane（2）, 3,9-（4-methylphenyl）-2,4,8,10-tetraoxaspiro [5.5] -undecane（3）, 4,4＇-（2,4,8,10-tetraoxaspiro[5.5]undecane-3,9-diyl）dibenzoic acid（4） and 3,9-di（4-formyl-phenyl）-2,4,8,10-tetraoxa-spiro[5.5]-undecane（5） were synthesized by grinding pentaerythritol with benzaldehyde, 4-methoxybenzaldehyde, 4-methylbenzaldehyde, 4-carboxybenzaldehyde or terephthalaldehyde monoacetal in the presence of InI3r3 under solvent-free conditions. A normal phase HPLC method was successfully developed to resolve entantiomers of compounds 1--5 on a chiral column. Specific optical rotation of R or S entantiomers（1） was determined and the corresponding configurations were proposed based on Lowe＇s rule.展开更多
A series of spiro, β-Lactams, and thiazolidinones incorporating compounds 4 have been synthesized by cycloaddition reaction of, chloroacetyl chloride and mercaptoacetic acid with the synthesized Shiff,s bases 5a-c to...A series of spiro, β-Lactams, and thiazolidinones incorporating compounds 4 have been synthesized by cycloaddition reaction of, chloroacetyl chloride and mercaptoacetic acid with the synthesized Shiff,s bases 5a-c to give new spiro β- Lactam 6a-c and spiro thiazolidinone 7a-c the cycloaddition were characterized by spectral data including HNMR, 13C-NMR, IR and elemental analysis.展开更多
The crystal of the title compound 6 has been prepared and determined by X-ray diffraction analysis. It belongs to the orthorhombic system, space group P212121 with a = 10.195(2), b = 11.955(2), c = 14.335(3) ?, C16H...The crystal of the title compound 6 has been prepared and determined by X-ray diffraction analysis. It belongs to the orthorhombic system, space group P212121 with a = 10.195(2), b = 11.955(2), c = 14.335(3) ?, C16H21BrO7, Mr = 405.24, V = 1747.0(6) ?3, Z = 4, Dc = 1.541 g/cm3, μ = 2.387 mm-1, F(000) = 832, R = 0.0266 and wR = 0.0348 for 2110 observed reflections with I > 2σ(I). The crystal exhibits a characteristic spiral structure consisting of one cyclopropane and two butyrolactones with envelope configuration. The intermolecular hydrogen bond between C(16)– H(16)…O(1) and C(3)–H(3)…O(2) has been observed in the crystal lattice.展开更多
The X2Ge=Si： （X = H, Me, F, reaction is a new area for the study of silylene between singlet CI2Ge=Si： and formaldehyde CI, Br, Ph, At...） is a new species. Its cycloaddition chemistry. The mechanism of cycloaddit...The X2Ge=Si： （X = H, Me, F, reaction is a new area for the study of silylene between singlet CI2Ge=Si： and formaldehyde CI, Br, Ph, At...） is a new species. Its cycloaddition chemistry. The mechanism of cycloaddition reaction has been investigated with CCSD（T）//MP2/6-31G＊ method. From the potential energy profile, it can be predicted that the reaction has two competitive dominant reaction pathways. The reaction rule presented is that the two reactants firstly form a four-membered Ge-heterocyclic ring silylene through the [2＋2] cycloaddition reaction. Owing to the 3p unoccupied orbital of Si： atom in the four-membered Ge-heterocyclic ring silylene and the π orbital of formaldehyde forming a π-p donor-acceptor bond, the four-membered Ge-heterocyclic ring silylene further combines with formaldehyde to form an intermediate. Because the Si： atom in intermediate shows sp3 hybridization after transition state, the intermediate isomerizes to a spiro-Si-heterocyclic ring compound involving Ge via a transition state. Simultaneously, the ring strain of the four-membered Ge-heterocyclic ring silylene makes it isomerize to a twisted four-membered ring product. The research result indicates the laws of cycloaddition reaction between X2Ge=Si： （X = H, Me, F, C1, Br, Ph, Ar...） and the asymmetric g-bonded compounds, which are significant for the synthesis of small-ring and spiro-Si-heterocyclic ring compound involving Ge The study extends the research area and enriches the research content of silvlene chemistrv.展开更多
The title compound 3,9-bis（pyridin-2-yl）-2,4,8,10-tetraoxaspiro[5.5]undecane 4（C17H18N2O4） has been synthesized by the reaction of 2,2-bis（hydroxymethyl）propane-1,3-diol with pyridine-2-carbaldehyde in the prese...The title compound 3,9-bis（pyridin-2-yl）-2,4,8,10-tetraoxaspiro[5.5]undecane 4（C17H18N2O4） has been synthesized by the reaction of 2,2-bis（hydroxymethyl）propane-1,3-diol with pyridine-2-carbaldehyde in the presence of p-toluenesulfonic acid,and characterized by IR,1H-NMR and X-ray single-crystal diffraction.The crystal belongs to monoclinic system,space group C2/c with a = 25.133（2）,b = 5.7219（5）,c = 21.942（2）（A°） ,β = 99.145（2）°,V = 3115.3（5）（A°）^3,Z = 8,Dc = 1.340 g/cm^3,Mr = 314.33,F（000） = 1328,μ = 0.097 mm-1,MoKa radiation（λ = 0.71073）,R = 0.0352 and wR = 0.1022 for 2486 observed reflections with I 〉 2σ（I）.X-ray analysis reveals that the two 1,3-dioxane rings passing through the central spiro-C atom both adopt chair conformation.Intermolecular C-H…π,C-H…O and C-H…N weak interactions link the molecules to form a three-dimensional samdwich,which are effective in the stabilization of the crystal structure.展开更多
X2Si=Sn:(X = H, Me, F, Cl, Br, Ph, Ar…) are new species of chemistry. The cycloaddition reaction of X2Si=Sn: is a new study field of stannylene chemistry. To explore the rules of cycloaddition reaction between X2Si=S...X2Si=Sn:(X = H, Me, F, Cl, Br, Ph, Ar…) are new species of chemistry. The cycloaddition reaction of X2Si=Sn: is a new study field of stannylene chemistry. To explore the rules of cycloaddition reaction between X2Si=Sn: and the symmetric p-bonded compounds, the cycloaddition reactions of Cl2Si=Sn: and ethylene were selected as model reactions in this paper.The mechanism of cycloaddition reaction between singlet Cl2Si=Sn: and ethylene has been first investigated with the MP2/GENECP(C, H, Cl, Si in 6-311++G**;Sn in LanL2dz) method in this paper. From the potential energy profile, it could be predicted that the reaction has one dominant reaction channel. The reaction rule presented is that the 5p unoccupied orbital of Sn in Cl2Si=Sn: and the π orbital of ethylene forming a p→p donor-acceptor bond, resulting in the formation of an intermediate. Instability of the intermediate makes it isomerize to a four-membered Si-heterocyclic ring stannylene. Because the 5p unoccupied orbital of Sn atom in the four-membered Si-heterocyclic ring stannylene and the π orbital of ethylene form a p→p donor-acceptor bond, the four-membered Si-heterocyclic ring stannylene further combines with ethene to form another intermediate. Because the Sn atom in the intermediate shows sp3 hybridization after transition state, the intermediate isomerizes to a Si-heterocyclic spiro-Sn-heterocyclic ring compound. The research result indicates the laws of cycloaddition reaction between X2Si=Sn: and the symmetric π-bonded compounds. The study opens up a new research field for stannylene chemistry.展开更多
基金supported by the Fundamental Research Funds for the Central Universities(2023QN1009)Xuzhou Basic Research Project(KC23018)+1 种基金China University of Mining and Technology(CUMT)Open Sharing Fund for Large-scale Instruments and Equipment(DYGX-2024-34)Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘High-energy-density(HED)fuel(e.g.widely used JP-10 and RJ-4),featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combustion heat can provide more propulsion energy.To reduce the reliance on petroleum source,it is highly desirable to develop renewable alternatives for the production of strained polycyclic HED fuel,but which remains a big challenge because of the inaccessibility caused by the high strain,We herein demonstrate a three-step catalytic route towards highly strained C_(17)and C_(18)spirofuel with biomass feedstocks.The process includes catalytic aldol condensation of renewable cyclohexanone/cyclopentanone with benzaldehyde,catalytic spiro Diels-Alder(D-A)reaction of aldol adduct with isoprene,and catalytic hydrodeoxygenation.The key spiro D-A reaction is enabled by the catalysis of heterogeneous Lewis acidic ionic liquid.The chloroaluminate IL,formed by benign urea and AICl3,exhibits good catalytic performance and reusability for this step.An eventual hydrodeoxygenation(HDO)over Pd/C and H-Y produces strained tricyclic spirofuel with density>0.93 g/mL,combustion heat>41 MJ/L and freezing point<-40℃,which are better than the properties of tactical fuel RJ-4.Therefore,it is anticipated that the as-prepared renewable fuels have the potential to replace traditional petroleum-derived HED fuels.
基金supported by the Natural Science Foundation of Shandong Province (No. Y2008B29)
文摘Two novel spiro compounds,3-benzylidene-1,5-dioxaspiro[5.5]undecane-2,4-dione 1 and 3-（2-fluorobenzylidene）-1,5-dioxaspiro[5.5]undecane-2,4-dione 2,have been synthesized and characterized by X-ray single-crystal diffraction,IR and elemental analysis.Compound 1 belongs to the monoclinic system,space group P21/n with a=12.326（3）,b=5.6420（11）,c=20.089（4）,β= 101.79（3）o,C16H16O4,Mr= 272.29,V=1367.7（5）3,Z=4,Dc=1.322g/cm3,F（000）=576,μ（MoKa）=0.095 mm-1,the final R=0.0420 and wR=0.1159.Compound 2 is of monoclinic system,space group P21/n with a=12.283（3）,b=5.6367（11）,c=20.055（4）,β=102.00（3）o,C16H15FO4,Mr=290.28,V=1358.2（5）3,Z=4,Dc=1.420 g/cm3,F（000）=608,μ（MoKa）=0.110 mm-1,the final R=0.0353 and wR=0.0860.
基金financial supported by National Basic Research Program of China(973 Program,No.2010CB126100)National High Technology Research Development Program of China(863 Program,No.2011AA10A207)+4 种基金Key Projects in the National Science & Technology Pillar Program(No.2011BAE06B05)National Natural Science Foundation of China(No.21372079)Shanghai Education Committee(No.12ZZ057)the Fundamental Research Funds for the Central Universitiespartly supported by Australia DC Foundation
文摘Spiro heterocycles frequently occur in bioactive molecules. In the pursuit of neonicotinoids with spiro hererocycles, three types of novel neonicotinoids with spirobenzofuranone, spirooxindole or spiroacenaphythylenone framework were designed and synthesized. Insecticidal evaluation showed that some of spirobenzofuranone containing neonicotinoids exhibited moderate activity against cowpea aphid, armyworm or brown planthopper.
基金supported by the National Natural Science Foundation of China(No.29872015,29832030)
文摘The photochromic spiropyrans and spirooxazine having a succinimidyl ester or isothiocyanate pendant group can form covalent products with transaminated DNA. The absorption spectra and solid reflection spectra of modified DNA with these photochromic spiro compounds were investigated.
基金support from the National Natural Science Foundation of China(No.21871067)the Natural Science Foundation of Guangdong Province(Nos.2018A030313038 and 2021A1515010190)+3 种基金the Shenzhen Fundamental Research Projects(No.JCYJ20180306171838187)the Harbin Institute of Technology(Shenzhen)(Talent Development Starting Fund from Shenzhen Government)the Open Project Program of State Key Laboratory of Elemento-Organic Chemistry(No.202009)the Guangdong Provincial Key Laboratory of Catalysis(No.2020B121201002)。
文摘A novel class of chiral spiro-fused bisoxazoline ligands possessing a deep chiral pocket was prepared.The developed ligands have been employed in the nickel-catalyzed highly enantioselective Michael-type Friedel-Crafts reaction, affording the products bearing a trifluoromethylated all-carbon quaternary stereocenter with moderate to excellent yields(up to 99%) and good to excellent enantioselectivies(up to> 99.9% ee). Moreover, a proposed model of chiral pocket revealed that the attack of indole from the Re-face of β-CF_(3)-β-disubstituted nitroalkene was favorable.
基金the National Natural Science Foundation of China for financial support.(Grant Nos.20072018 and 20372039).
文摘A series of photo active azido analogues have been synthesized and their photochromic properties have also been investigated by UV-Vis spectrum. It will be used for the rapid and reliable preparation of large amounts of stable, non-radioactive labeled DNA and RNA hybridization probes. And it is supposed to be easily detected for its photochromic properties.
基金the financial support from Xinxiang Medical University
文摘Novel spiro[dibenzo[a,i]xanthene-14,3＇-indoline]-2＇,8,13-triones were prepared by the three-component reaction ofβ-naphthol, isatins,and 2-hydroxy-1,4-naphoquinone in the presence of a catalytic amount of H_4SiW_（12）O_（40）.This protocol provides a simple one-step procedure with the advantages of easy work-up,mild reaction conditions and environmentally benign.
基金National Basic Research Program of China (973 Program, Grant No. 2009CB930300)National Natural Science Foundation of China (Grant No.20501004 and 20871021)
文摘We investigated the bio-distributions of [125 I]Spiro-I formulated in sterically stabilized liposomes （SSL） or targeted liposomes （SSTL） in mice,especially their brain uptake.The [125 I]Spiro-I liposomes were prepared by film-ultrasound dispersion method.Cereport （RMP-7） was covalently conjugated with DSPE-PEG,which was attached to the surface of SSL to form SSTL.The encapsulation efficiencies （ee%） of [125 I]Spiro-I-SSL and [125 I]Spiro-I-SSTL were 97.47%±4.01% and 93.02%±2.98%,respectively.The average particle sizes were （66.47±0.76） nm and （71.40±0.45） nm,respectively.After intravenous administration,[125 I]Spiro-I was quickly eliminated from blood.SSL could prolong the retention time of [125 I]Spiro-I in blood and SSTL improved its brain uptake.The AUC of [125 I]Spiro-I-SSTL in brain was increased by 1.52 times as compared to [125 I]Spiro-I,indicating that SSTL could be used for the formulation of [125 I]Spiro-I for the imaging of central nervous system （CNS）.
基金financially supported by the National Natural Science Foundation of China (Nos. 21172189, 21572196)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The BF_3OEt_2 catalyzed one-pot 1,3-dipolar cycloaddition reaction of benzylamines,isatins and dimethyl acetylenedicarboxylate in dry methylene dichloride afforded the functionalized dihydrospiro[indoline-3,2＇-pyrroles]in moderate to good yields and with high diastereoselectivity.The reaction was accomplished by the tandem 1,3-dioplar cycloaddition of in situ generated azomethine ylide with acetylenedicarboxylate and the nucleophilic addition of pyrrole ring to second molecular acetylenedicarboxylate.
文摘A rapid and efficient, one pot synthesis of spirooxindole derivatives has been attempted by three- component reaction of isatin, malononitrile and carbonyl compound possessing a reactive c^-methylene group by using task specific ionic liquid, 1-butyl-3-methyl imidazolium hydroxide [bmim]OH as a catalyst. The important features of this methodology are straight forward route in short reaction time at room temperature and avoid any hazardous organic solvent, toxic catalyst, tedious purification step. Interestingly, this protocol is not only limited to mono-systems but also to the synthesis of newer bis- spirooxindole system. The separation of the product and reusability of the catalyst are easy with excellent yield. The [bmim]OH catalyst system could be reused up to five recycles without appreciable loss of activity.
基金supported by the National Natural Science Foundation of China(No.51102114)
文摘X2Si=Ge： （X = H, Me, F, CI, Br, Ph, Ar...） is a new species. Its cycloaddition reaction is a new area for the study of germylene chemistry. The mechanism of cycloaddition reaction between singlet state Me2Si=Ge： and formaldehyde has been investigated with the CCSD（T）//MP2/cc-pvtz method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rule presented is that the two reactants first form a four-membered Si-heterocyclic ring germylene through the [2＋2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge： atom in the four-membered Si-heterocyclic ring germylene and the π orbital of formaldehyde form a π→p donor-acceptor bond, the four-membered Si-heterocyclic ring germylene further combines with formaldehyde to form an intermediate. Because the Ge atom in the intermediate undergoes sp^3 hybridization after transition state, then the intermediate isomerizes to a spiro-Ge-heterocyclic ring compound involving Si via a transition state. The research result indicates the laws of cycloaddition reaction between HzSi=Ge： and formaldehyde. It has important reference value for the cycloaddition reaction between X2Si=Ge： （X = H, Me, F, CI, Br, Ph, Ar…） and asymmetric to-bonded compounds, which is significant for the synthesis of small-ring and spiro-Ge-heterocyclic compounds involving Si. The study extends research area and enriches the research content of germylene chemistry.
基金financial support from the Research Council of the University of Sistan and Baluchestan and Islamic Azad University of Yazd
文摘A green,convenient,high yielding and one-pot procedure for the synthesis of novel spiro[benzo[α]pyrano[2,3-c]phenazine]derivatives by domino multi-component condensation reaction between 2-hydroxynaphthalene-l,4-dione,benzene-l,2-diamines,ninhydrine,and malononitrile in the presence of a catalytic amount of 1,3-dimethyl-7H-purine-2,6-dione（theophylline） as an expedient,eco-friendly and reusable solid base catalyst under thermal,microwave irradiation and solvent-free conditions.This procedure has also been applied successfully for the synthesis of benzo[α]pyrano[2,3-c]phenazines.
基金the National Natural Science Foundation of China(No.20472064)the Natural Science Foundation of Tian- jin city, China(No.040884311)
文摘Chiral spirocyclic compounds have attracted the attention of scholars and scientists owing to their potential applications in the pharmaceutical industry as either active pharmaceutical ingredients, catalysts in synthesizing active enantiomers, or as surface modifiers on silica particles to resolve entantiomers. In this study, five spiro compounds of 3,9-diphenyl-2,4,8,10-tetraoxaspiro[5.5]-undecane（1）, 3,9-（4-methoxyphenyl）-2,4,8,10-tetraoxaspiro [5.5] -undecane（2）, 3,9-（4-methylphenyl）-2,4,8,10-tetraoxaspiro [5.5] -undecane（3）, 4,4＇-（2,4,8,10-tetraoxaspiro[5.5]undecane-3,9-diyl）dibenzoic acid（4） and 3,9-di（4-formyl-phenyl）-2,4,8,10-tetraoxa-spiro[5.5]-undecane（5） were synthesized by grinding pentaerythritol with benzaldehyde, 4-methoxybenzaldehyde, 4-methylbenzaldehyde, 4-carboxybenzaldehyde or terephthalaldehyde monoacetal in the presence of InI3r3 under solvent-free conditions. A normal phase HPLC method was successfully developed to resolve entantiomers of compounds 1--5 on a chiral column. Specific optical rotation of R or S entantiomers（1） was determined and the corresponding configurations were proposed based on Lowe＇s rule.
文摘A series of spiro, β-Lactams, and thiazolidinones incorporating compounds 4 have been synthesized by cycloaddition reaction of, chloroacetyl chloride and mercaptoacetic acid with the synthesized Shiff,s bases 5a-c to give new spiro β- Lactam 6a-c and spiro thiazolidinone 7a-c the cycloaddition were characterized by spectral data including HNMR, 13C-NMR, IR and elemental analysis.
基金Supported by the National Natural Science Foundation of China (No. 29672004)
文摘The crystal of the title compound 6 has been prepared and determined by X-ray diffraction analysis. It belongs to the orthorhombic system, space group P212121 with a = 10.195(2), b = 11.955(2), c = 14.335(3) ?, C16H21BrO7, Mr = 405.24, V = 1747.0(6) ?3, Z = 4, Dc = 1.541 g/cm3, μ = 2.387 mm-1, F(000) = 832, R = 0.0266 and wR = 0.0348 for 2110 observed reflections with I > 2σ(I). The crystal exhibits a characteristic spiral structure consisting of one cyclopropane and two butyrolactones with envelope configuration. The intermolecular hydrogen bond between C(16)– H(16)…O(1) and C(3)–H(3)…O(2) has been observed in the crystal lattice.
基金supported by the National Natural Science Foundation of China(No.51102114)
文摘The X2Ge=Si： （X = H, Me, F, reaction is a new area for the study of silylene between singlet CI2Ge=Si： and formaldehyde CI, Br, Ph, At...） is a new species. Its cycloaddition chemistry. The mechanism of cycloaddition reaction has been investigated with CCSD（T）//MP2/6-31G＊ method. From the potential energy profile, it can be predicted that the reaction has two competitive dominant reaction pathways. The reaction rule presented is that the two reactants firstly form a four-membered Ge-heterocyclic ring silylene through the [2＋2] cycloaddition reaction. Owing to the 3p unoccupied orbital of Si： atom in the four-membered Ge-heterocyclic ring silylene and the π orbital of formaldehyde forming a π-p donor-acceptor bond, the four-membered Ge-heterocyclic ring silylene further combines with formaldehyde to form an intermediate. Because the Si： atom in intermediate shows sp3 hybridization after transition state, the intermediate isomerizes to a spiro-Si-heterocyclic ring compound involving Ge via a transition state. Simultaneously, the ring strain of the four-membered Ge-heterocyclic ring silylene makes it isomerize to a twisted four-membered ring product. The research result indicates the laws of cycloaddition reaction between X2Ge=Si： （X = H, Me, F, C1, Br, Ph, Ar...） and the asymmetric g-bonded compounds, which are significant for the synthesis of small-ring and spiro-Si-heterocyclic ring compound involving Ge The study extends the research area and enriches the research content of silvlene chemistrv.
基金supported by the National Natural Science Foundation of China (No. 20872051 and 21002009)the Scientific and Technological Project of Changzhou (CJ20115019)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The title compound 3,9-bis（pyridin-2-yl）-2,4,8,10-tetraoxaspiro[5.5]undecane 4（C17H18N2O4） has been synthesized by the reaction of 2,2-bis（hydroxymethyl）propane-1,3-diol with pyridine-2-carbaldehyde in the presence of p-toluenesulfonic acid,and characterized by IR,1H-NMR and X-ray single-crystal diffraction.The crystal belongs to monoclinic system,space group C2/c with a = 25.133（2）,b = 5.7219（5）,c = 21.942（2）（A°） ,β = 99.145（2）°,V = 3115.3（5）（A°）^3,Z = 8,Dc = 1.340 g/cm^3,Mr = 314.33,F（000） = 1328,μ = 0.097 mm-1,MoKa radiation（λ = 0.71073）,R = 0.0352 and wR = 0.1022 for 2486 observed reflections with I 〉 2σ（I）.X-ray analysis reveals that the two 1,3-dioxane rings passing through the central spiro-C atom both adopt chair conformation.Intermolecular C-H…π,C-H…O and C-H…N weak interactions link the molecules to form a three-dimensional samdwich,which are effective in the stabilization of the crystal structure.
基金supported by the National Natural Science Foundation of China(No.51102114)
文摘X2Si=Sn:(X = H, Me, F, Cl, Br, Ph, Ar…) are new species of chemistry. The cycloaddition reaction of X2Si=Sn: is a new study field of stannylene chemistry. To explore the rules of cycloaddition reaction between X2Si=Sn: and the symmetric p-bonded compounds, the cycloaddition reactions of Cl2Si=Sn: and ethylene were selected as model reactions in this paper.The mechanism of cycloaddition reaction between singlet Cl2Si=Sn: and ethylene has been first investigated with the MP2/GENECP(C, H, Cl, Si in 6-311++G**;Sn in LanL2dz) method in this paper. From the potential energy profile, it could be predicted that the reaction has one dominant reaction channel. The reaction rule presented is that the 5p unoccupied orbital of Sn in Cl2Si=Sn: and the π orbital of ethylene forming a p→p donor-acceptor bond, resulting in the formation of an intermediate. Instability of the intermediate makes it isomerize to a four-membered Si-heterocyclic ring stannylene. Because the 5p unoccupied orbital of Sn atom in the four-membered Si-heterocyclic ring stannylene and the π orbital of ethylene form a p→p donor-acceptor bond, the four-membered Si-heterocyclic ring stannylene further combines with ethene to form another intermediate. Because the Sn atom in the intermediate shows sp3 hybridization after transition state, the intermediate isomerizes to a Si-heterocyclic spiro-Sn-heterocyclic ring compound. The research result indicates the laws of cycloaddition reaction between X2Si=Sn: and the symmetric π-bonded compounds. The study opens up a new research field for stannylene chemistry.
