The crystal structure of the title compound ethyl 3-（4-chlorophenyl）-3,4-dihydro-6- methyl-4-oxo-2-（pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate （C20H20ClN3O4, Mr= 401.84） has been prepared and determined...The crystal structure of the title compound ethyl 3-（4-chlorophenyl）-3,4-dihydro-6- methyl-4-oxo-2-（pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate （C20H20ClN3O4, Mr= 401.84） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215（9）, b = 8.5311（4）, c = 21.6886（9） A^°, β = 91.607（1）°, V = 3814.0（3）A^°^3, Z = 8, Dc = 1.400 g/cm^3, F（000） = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.展开更多
Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis（4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl）methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-...Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis（4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl）methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis（pyranon-3-yl）methane hybrids with potential biological activities were constructed.展开更多
The title compound N-tert-butyl-N(-(2,4-dichlorobenzoyl)-N-[1-(4-chlorophenyl)- 1,4-dihydro-6-methylpyridazine-4-oxo-3-carbonyl]hydrazine [(C23H_21N4O3Cl3)2·1.5H_2O, Mr = 1042.60] was prepared by the reaction of ...The title compound N-tert-butyl-N(-(2,4-dichlorobenzoyl)-N-[1-(4-chlorophenyl)- 1,4-dihydro-6-methylpyridazine-4-oxo-3-carbonyl]hydrazine [(C23H_21N4O3Cl3)2·1.5H_2O, Mr = 1042.60] was prepared by the reaction of 1-(4-chlorophenyl)-1,4-dihydro-4-oxo-6- methylpyridazine-3-carboxylic acid with chloroformate ethyl ester, then with N′-tert-butyl-N- (2,4-dichlorobenzoyl) hydrazine in the present of triethylamine. The crystal structure has been determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P21/c, with unit cell constants a =11.4948(9), b=12.7495(10), c=35.854(3) ?, β =92.964(2)°, Z=4, V=5247.6(7) ?3, Dc = 1.320 Mg/m3, F(000) = 2156 , μ (MoKa)= 0.385, R = 0.0661, wR = 0.1875, for 9151 observed reflections( I >2σ(I)). The structure is a dimer linked by intermolecular hydrogen bond which can be observed between N(1)- H...O(6), N(5)- H...O(3). The distances are 2.068 and 2.027? respectively.展开更多
The title compound, 4-tert-butyl-6-（4-chlorophenyl）-3,6-dihydro-2H-1,3-thiazin- 2-iminium chloride （C14H18C12N2S）, has been synthesized by the reaction of 1-（4-chlorophenyl）- 4,4-dimethylpent-1-en-3-one with thi...The title compound, 4-tert-butyl-6-（4-chlorophenyl）-3,6-dihydro-2H-1,3-thiazin- 2-iminium chloride （C14H18C12N2S）, has been synthesized by the reaction of 1-（4-chlorophenyl）- 4,4-dimethylpent-1-en-3-one with thiourea, and its crystal structure was determined by single- crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P211c with a = 16.3064（11）, b = 9.4471（6）, c = 11.2626 （8）A, β = 108.400（1）°, Z = 4, V = 1646.28（19） A^3, Mr = 317.26, Dc = 1.280 g/cm^3, S = 1.078,μ = 0.510 mm^-1, F（000） = 664, the final R = 0.0514 and wR = 0.1412 for 3210 observed reflections （I 〉 2σ（I））. The thiazine ring system displays a twisted boat conformation, and three N-H,..Cl hydrogen bonds exist in the crystal. The combination of two N-H...Cl hydrogen bonds generate an R2^1 （6） ring.展开更多
The electrochemiluminescence (ECL) of a new reagent 6- (2-hydroxy- 4 diethy laminophenylazo)-2,3-dihydro-1 ,4-phthalazine-1,4-dione (HDEA) in a basic aqueous so lution was studied by using the apparatus designed by ou...The electrochemiluminescence (ECL) of a new reagent 6- (2-hydroxy- 4 diethy laminophenylazo)-2,3-dihydro-1 ,4-phthalazine-1,4-dione (HDEA) in a basic aqueous so lution was studied by using the apparatus designed by ourselves. Trace amounts of silver ( Ⅰ ) shows a significant effect on the efficiency of light emission of HDEA during a positive trigonometrical wave pulse was exerted on the solution. The linear relationship between the light intensity and the concentration of silver( Ⅰ ) occurs in the range of 5. 0×10-8 to 3. 0×10-8 mol/L Ag(Ⅰ ) in a medium of KOH-KCl-HDEA (pH= 12. 8). The detection limit of the method is 2. 0×10-8 mol/LAg( Ⅰ ), and the r. s. d. for 1.0×10-7 mo)/L Ag ( Ⅰ ) is 5%. Of 21 metal ions concerned, only nickel( Ⅱ ), cerium( Ⅳ ) and cobalt( Ⅱ ) interfere the silver detection seriously; Ⅰ and Br also have some interference.展开更多
The title compound （R）-N′-[2-（4-methoxy-6-chloro）-pyrimidyl]-N-[3-methyl-2-（4- chlorophenyl）butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic ...The title compound （R）-N′-[2-（4-methoxy-6-chloro）-pyrimidyl]-N-[3-methyl-2-（4- chlorophenyl）butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic data： C17H18C12N4O3, Mr = 397.25, monoclinic, space group P21/c, a = 12.331（2）, b = 14.025（3）, c = 23.085（5） A, β = 99.607（4）°, Z = 8, V = 3936.2（13） A3, Dc = 1.341 g/cm^3, F（000） = 1648, R = 0.0718, wR = 0.1585 and/t（MoKα） = 0.353 mm^-1. The preliminary biological tests showed that the title compound has definite insecticidal and fungicidal activities.展开更多
The title compound ethyl 2-（6-（1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2（3H）- yl）-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate 3 was synthesized by the reaction of ethyl 2-（6-amino-7-fluoro-3-ox...The title compound ethyl 2-（6-（1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2（3H）- yl）-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate 3 was synthesized by the reaction of ethyl 2-（6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469（2）, b = 16.7715（5）, c = 13.7153（4） A, β= 104.9680（10）°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08（10） ,A3, Z= 4, Dc = 1.376 g/cm3, F（000） = 904, T= 296（2） K, R = 0.0508 and wR = 0.1478.展开更多
Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has bee...Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has been determined from single crystal X-ray diffraction data. The hydrated C7H5N2NaO52.5H2O crystallizes in the monoclinic space group C2/c, with a(?) 16.408(3);b(?) 12.446(3);c(?) 13.716(3);(o) 126.34(3). The planar organic anion exists in a triketo-dihydroxyimino form with the C–O and C–N distances from 1.220(2) to 1.271(2)?? and from 1.292(2) to 1.293?? respectively. In the IR spectrum of I, the sharp absorption band occurred at 1681 cm-1 due to C=O stretching indicating the strong H-interactions. The correlations of theoretical (DFT-B3LYP/aug-cc-pVDZ) and experimental UV-vis absorption spectra in neutral and alkaline ethanolic solutions showed the existence of hydroxyimino-nitroso tautomerism while ionization of I.展开更多
The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as t...The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as the acid scavenger, whereas the reactions gave unexpected 8-substituted products N-（8-chloro-4-methyl-2-oxo-2H-furo-[2,3-h]chromen-9-yl）amides （5a-c） and 4-methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloates （6d-e） by using excessive acid chlorides. The structures of 10 new compounds were determined by 1H NMR, 13C NMR, MS and HRMS, and the possible mechanism for the formation of unexpected products 5a--c and 6d-e was also proposed.展开更多
Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). Th...Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). The reaction of 2 with hydrazine hydrate followed by diazotization reaction af-forded the 1,1’-(1,4-phenylenebis(3-amino-6-methyl-1H-pyrazolo[3,4-b]pyridine-4,5-diyl))bis(e-than-1-one) (3) and 1,1’-(1,4-phenylenebis(3-(chlorodiazenyl)-6-methyl-1H-pyrazolo[3,4-b]-pyridine-4,5-diyl))bis(ethan-1-one) (4) respectively. On the other hand, reaction of 4 with malononitrile, 2-cyanoethanethioamide, ethyl acetoacetate, acetyl acetone, ethyl benzoylacetate, diethylmalonate, ethyl cyanoacetate and phenacylbromide aiming to build up pyrazolotriazine or pyrazole ring on the ring system of 4. Structures of all newly synthesized heterocyclic compounds in the present study were confirmed by considering the data of IR, 1H NMR, mass spectra as well as that of elemental analyses.展开更多
The positive effect of levodopa in the treatment of Parkinson’s disease,although it is limited in time and has severe side effects,has encouraged the scientific community to look for new drugs that can stop the neuro...The positive effect of levodopa in the treatment of Parkinson’s disease,although it is limited in time and has severe side effects,has encouraged the scientific community to look for new drugs that can stop the neurodegenerative process or even regenerate the neuromelanin-containing dopaminergic nigrostriatal neurons.Successful preclinical studies with coenzyme Q10,mitoquinone,isradipine,nilotinib,TCH346,neurturin,zonisamide,deferiprone,prasinezumab,and cinpanemab prompted clinical trials.However,these failed and after more than 50 years levodopa continues to be the key drug in the treatment of the disease,despite its severe side effects after 4–6 years of chronic treatment.The lack of translated successful results obtained in preclinical investigations based on the use of neurotoxins that do not exist in the human body as new drugs for Parkinson’s disease treatment is a big problem.In our opinion,the cause of these failures lies in the experimental animal models involving neurotoxins that do not exist in the human body,such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and 6-hydroxydopamine,that induce a very fast,massive and expansive neurodegenerative process,which contrasts with the extremely slow one of neuromelanin-containing dopaminergic neurons.The exceedingly slow progress of the neurodegenerative process of the nigrostriatal neurons in idiopathic Parkinson’s patients is due to(i)a degenerative model in which the neurotoxic effect of an endogenous neurotoxin affects a single neuron,(ii)a neurotoxic event that is not expansive and(iii)the fact that the neurotoxin that triggers the neurodegenerative process is produced inside the neuromelanin-containing dopaminergic neurons.The endogenous neurotoxin that fits this degenerative model involving one single neuron at a time is aminochrome,since it(i)is generated within neuromelanin-containing dopaminergic neurons,(ii)does not cause an expansive neurotoxic effect and(iii)triggers all the mechanisms involved in the neurodegenerative process of the nigrostriatal neurons in idiopathic Parkinson’s disease.In conclusion,based on the hypothesis that the neurodegenerative process of idiopathic Parkinson’s disease corresponds to a single-neuron neurodegeneration model,we must search for molecules that increase the expression of the neuroprotective enzymes DT-diaphorase and glutathione transferase M2-2.It has been observed that the activation of the Kelch-like ECH-associated protein 1/nuclear factor(erythroid-derived 2)-like 2 pathway is associated with the transcriptional activation of the DT-diaphorase and glutathione transferase genes.展开更多
Aim To investigate the alkylation of 2-thiopyrimidine. Methods Treating the starting material 2-thiopyrimidine with chloromethyl ethers via a procedure of K2CO3 in DMF or with alkyl halide in CH3ONa-CH3OH at room temp...Aim To investigate the alkylation of 2-thiopyrimidine. Methods Treating the starting material 2-thiopyrimidine with chloromethyl ethers via a procedure of K2CO3 in DMF or with alkyl halide in CH3ONa-CH3OH at room temperature, to obtain the corresponding regioselective 2-S-allkyl pyrimidines. The products were determined by JH NMR, 2D NMR, IR and MS spectra. Results 2-S-alkyl-pyrimidines were regioselectively synthesized. Conclusion In different conditions with different alkyl halides, 2- thiouracil could be converted into the corresponding 2-S-alkylpyrimidines regioselectively.展开更多
In the interest of driving down the cost of DCM-type light emitting materials, we have found a new approach to prepare 2-（t-butyl）-6-methy1-4H-pyrone, which is cost effective and more amenable to large scale product...In the interest of driving down the cost of DCM-type light emitting materials, we have found a new approach to prepare 2-（t-butyl）-6-methy1-4H-pyrone, which is cost effective and more amenable to large scale production than the reported method. Furthermore, three new DCM-type dyes, N,N-bis-[p-（2-（4-dicyanomethylene-6-t-butyl-4H- pyran-2-yl）-vinyl）-phenyl]-4-t-butyl-aniline （BDCM-BA）, N,N-bis-[p-（2-（4-dicyanomethylene-6-t-butyl-4H-pyran- 2-yl）-vinyl）-phenyl]aniline （BDCM-A） and N,N-bis-[p-（2-（4-dicyanomethylene-6-t-butyl-4H-pyran-2-yl）-vinyl）- phenyl]-4-methoxyl-aniline （BDCM-MA） were synthesized in good yields using 2-（t-butyl）-6-methyl-4H-pyrone as starting material. They can be utilized in OLEDs as nondoped red emitting materials as the result of the restricted concentration quenching effect.展开更多
3-（4-Hydroxyphenyl）-4-methyl-6-methoxy-7-hydroxycoumarin （2a） and its analogues with different substituents at the p-position of 3-phenyl group were designed and synthesized as the non-steroidal analogues of 2-met...3-（4-Hydroxyphenyl）-4-methyl-6-methoxy-7-hydroxycoumarin （2a） and its analogues with different substituents at the p-position of 3-phenyl group were designed and synthesized as the non-steroidal analogues of 2-methoxyestradiol （2-ME 1）. The desired compounds were synthesized via a novel and simple route and the effects of specific substituents on their antiangiogenesis activities were investigated with Human umbilical vein endothelial cells （HUVECs） proliferation assays. Preliminary biological screening showed that compounds 2a and 2d （IC50 = 61.0 and 76.7 ktM, respectively） have potential anti-angiogenesis activities. The bulk of the group at the p-position of 3-phenyl group likely play an important role in their activities.展开更多
Cultivation of an endophytic fungus Aspergillus niger EN-13 that was isolated from the inner tissue of the marine brown alga Colpomenia sinuosa resulted in the characterization of a new naphthoquinoneimine derivative,...Cultivation of an endophytic fungus Aspergillus niger EN-13 that was isolated from the inner tissue of the marine brown alga Colpomenia sinuosa resulted in the characterization of a new naphthoquinoneimine derivative, namely, 5,7-dihydroxy-2-[1-（4- methoxy-6-oxo-6H-pyran-2-yl）-2-phenylethylamino]-[ 1,4]naphthoquinone. The structure of the new compound was established on the basis of various NMR spectroscopic analyses including 2D NMR techniques, El-MS, and HR-ESI-MS. This compound displayed moderate antifungal activity.展开更多
A new halogenated biindole and a new apo-carotenone have been isolated from the ethanolic extract of the green alga Chaetomorpha basiretorsa Sethcell. On the basis of chemical and spectroscopic methods including 2D NM...A new halogenated biindole and a new apo-carotenone have been isolated from the ethanolic extract of the green alga Chaetomorpha basiretorsa Sethcell. On the basis of chemical and spectroscopic methods including 2D NMR technique, their structures have been elucidated as 4,4′-dichloro-5,5′-dibromo-7,7′-dimethoxy-2,2′-bi-1H-indole and 1′S*,4′R*-8-(4′-hydroxy-2′,6′,6′- trimethylcyclohex-2-enyl)-6-methyloct-3E,5E,7E-trien-2-one, respectively.展开更多
The present study observed the action of 1H-indole-2, 3-dione （isatin） on Bax protein expression in the substantia nigra of a Parkinson＇s disease animal model. Parkinson＇s disease-like behaviors were induced in C5...The present study observed the action of 1H-indole-2, 3-dione （isatin） on Bax protein expression in the substantia nigra of a Parkinson＇s disease animal model. Parkinson＇s disease-like behaviors were induced in C57BL/6J mice treated with 1-methyl-4-phenyl-1,2, 3, 6-tetrahydropyridine （MPTP） Bax protein expression was significantly reduced in isatin （100, 200 mg/kg）-pretreated mice. Results demonstrate that isatin plays a neuroprotective role in mice treated with MPTP by down-regulating Bax protein expression.展开更多
A new bisxanthone, named bijaponicaxanthone C, was isolated from the whole plant of Hypericum japonicum. The structure was elucidated as 6-[1’’,5’’,6’’-trihydroxy-2’’’-(β-hydroxy-β- methylethyl)-2’’’,3...A new bisxanthone, named bijaponicaxanthone C, was isolated from the whole plant of Hypericum japonicum. The structure was elucidated as 6-[1’’,5’’,6’’-trihydroxy-2’’’-(β-hydroxy-β- methylethyl)-2’’’,3’’’-dihydrofuran(5’’’,4’’’,3’’,4’’)xanthone-3’’’-oxyl]-1,3,5-trihydroxy-4-isoprenylxant- hone (1) on the basis of the spectral and chemical evidences.展开更多
基金supported by the Natural Science Foundation of Hubei Province (2006ABB016)Key Science Research Project of Hubei Provincial Department of Education (No.D200724001) the Science Research Project of Yunyang Medical College (No. 2006QDJ16)
文摘The crystal structure of the title compound ethyl 3-（4-chlorophenyl）-3,4-dihydro-6- methyl-4-oxo-2-（pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate （C20H20ClN3O4, Mr= 401.84） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215（9）, b = 8.5311（4）, c = 21.6886（9） A^°, β = 91.607（1）°, V = 3814.0（3）A^°^3, Z = 8, Dc = 1.400 g/cm^3, F（000） = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.
基金the National Natural Science Foundation of China(No.20772025)the Program for Science & Technology Innovation Talents in Universities of Henan Province(No.2008HASTIT006)the Natural Science Foundation of Department of Education of Henan Province(No.2008A150013).
文摘Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis（4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl）methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis（pyranon-3-yl）methane hybrids with potential biological activities were constructed.
文摘The title compound N-tert-butyl-N(-(2,4-dichlorobenzoyl)-N-[1-(4-chlorophenyl)- 1,4-dihydro-6-methylpyridazine-4-oxo-3-carbonyl]hydrazine [(C23H_21N4O3Cl3)2·1.5H_2O, Mr = 1042.60] was prepared by the reaction of 1-(4-chlorophenyl)-1,4-dihydro-4-oxo-6- methylpyridazine-3-carboxylic acid with chloroformate ethyl ester, then with N′-tert-butyl-N- (2,4-dichlorobenzoyl) hydrazine in the present of triethylamine. The crystal structure has been determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P21/c, with unit cell constants a =11.4948(9), b=12.7495(10), c=35.854(3) ?, β =92.964(2)°, Z=4, V=5247.6(7) ?3, Dc = 1.320 Mg/m3, F(000) = 2156 , μ (MoKa)= 0.385, R = 0.0661, wR = 0.1875, for 9151 observed reflections( I >2σ(I)). The structure is a dimer linked by intermolecular hydrogen bond which can be observed between N(1)- H...O(6), N(5)- H...O(3). The distances are 2.068 and 2.027? respectively.
基金supported by the National Project of Scientific and Technical Supporting Programs Funded by Ministry of Science & Technology of China (No 2006BAE01A01-4)
文摘The title compound, 4-tert-butyl-6-（4-chlorophenyl）-3,6-dihydro-2H-1,3-thiazin- 2-iminium chloride （C14H18C12N2S）, has been synthesized by the reaction of 1-（4-chlorophenyl）- 4,4-dimethylpent-1-en-3-one with thiourea, and its crystal structure was determined by single- crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P211c with a = 16.3064（11）, b = 9.4471（6）, c = 11.2626 （8）A, β = 108.400（1）°, Z = 4, V = 1646.28（19） A^3, Mr = 317.26, Dc = 1.280 g/cm^3, S = 1.078,μ = 0.510 mm^-1, F（000） = 664, the final R = 0.0514 and wR = 0.1412 for 3210 observed reflections （I 〉 2σ（I））. The thiazine ring system displays a twisted boat conformation, and three N-H,..Cl hydrogen bonds exist in the crystal. The combination of two N-H...Cl hydrogen bonds generate an R2^1 （6） ring.
文摘The electrochemiluminescence (ECL) of a new reagent 6- (2-hydroxy- 4 diethy laminophenylazo)-2,3-dihydro-1 ,4-phthalazine-1,4-dione (HDEA) in a basic aqueous so lution was studied by using the apparatus designed by ourselves. Trace amounts of silver ( Ⅰ ) shows a significant effect on the efficiency of light emission of HDEA during a positive trigonometrical wave pulse was exerted on the solution. The linear relationship between the light intensity and the concentration of silver( Ⅰ ) occurs in the range of 5. 0×10-8 to 3. 0×10-8 mol/L Ag(Ⅰ ) in a medium of KOH-KCl-HDEA (pH= 12. 8). The detection limit of the method is 2. 0×10-8 mol/LAg( Ⅰ ), and the r. s. d. for 1.0×10-7 mo)/L Ag ( Ⅰ ) is 5%. Of 21 metal ions concerned, only nickel( Ⅱ ), cerium( Ⅳ ) and cobalt( Ⅱ ) interfere the silver detection seriously; Ⅰ and Br also have some interference.
基金This work was sponsored by the National Key Technologies R & D Programs (No. 2004BA308A22-8)
文摘The title compound （R）-N′-[2-（4-methoxy-6-chloro）-pyrimidyl]-N-[3-methyl-2-（4- chlorophenyl）butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic data： C17H18C12N4O3, Mr = 397.25, monoclinic, space group P21/c, a = 12.331（2）, b = 14.025（3）, c = 23.085（5） A, β = 99.607（4）°, Z = 8, V = 3936.2（13） A3, Dc = 1.341 g/cm^3, F（000） = 1648, R = 0.0718, wR = 0.1585 and/t（MoKα） = 0.353 mm^-1. The preliminary biological tests showed that the title compound has definite insecticidal and fungicidal activities.
基金Supported by the National Natural Science Foundation of China (20872033, 20575019)Natural Science Foundation of Hunan Province (07JJ1003)+1 种基金Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) (KLCBTCMR2008-14)Scientific Research Fund of Science and Technology Department of Hunan Province (No. 2006GK3067)
文摘The title compound ethyl 2-（6-（1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2（3H）- yl）-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate 3 was synthesized by the reaction of ethyl 2-（6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469（2）, b = 16.7715（5）, c = 13.7153（4） A, β= 104.9680（10）°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08（10） ,A3, Z= 4, Dc = 1.376 g/cm3, F（000） = 904, T= 296（2） K, R = 0.0508 and wR = 0.1478.
文摘Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has been determined from single crystal X-ray diffraction data. The hydrated C7H5N2NaO52.5H2O crystallizes in the monoclinic space group C2/c, with a(?) 16.408(3);b(?) 12.446(3);c(?) 13.716(3);(o) 126.34(3). The planar organic anion exists in a triketo-dihydroxyimino form with the C–O and C–N distances from 1.220(2) to 1.271(2)?? and from 1.292(2) to 1.293?? respectively. In the IR spectrum of I, the sharp absorption band occurred at 1681 cm-1 due to C=O stretching indicating the strong H-interactions. The correlations of theoretical (DFT-B3LYP/aug-cc-pVDZ) and experimental UV-vis absorption spectra in neutral and alkaline ethanolic solutions showed the existence of hydroxyimino-nitroso tautomerism while ionization of I.
基金grants from the National Natural Science Foundation of China (No.20272010 and 20672022)
文摘The esterifications of 9-（hydroxyimino）-4-methyl-8,9-dihydrofuro[2,3-h]chromen-2-one （4） with acid chlorides afforded normal oxime-esters 3a-e in 35-78% yields in presence of excessive 4-dimethylaminopyridine as the acid scavenger, whereas the reactions gave unexpected 8-substituted products N-（8-chloro-4-methyl-2-oxo-2H-furo-[2,3-h]chromen-9-yl）amides （5a-c） and 4-methyl-2,9-dioxo-8,9-dihydro-2H-furo[2,3-h]chromen-8-ylcarboxyloates （6d-e） by using excessive acid chlorides. The structures of 10 new compounds were determined by 1H NMR, 13C NMR, MS and HRMS, and the possible mechanism for the formation of unexpected products 5a--c and 6d-e was also proposed.
文摘Reaction of 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile) (1) with methyl iodide afforded the 4,4’-(1,4-phenylene)bis(5-acetyl-6-methyl-2-(methylthio)nicotinonitrile) (2). The reaction of 2 with hydrazine hydrate followed by diazotization reaction af-forded the 1,1’-(1,4-phenylenebis(3-amino-6-methyl-1H-pyrazolo[3,4-b]pyridine-4,5-diyl))bis(e-than-1-one) (3) and 1,1’-(1,4-phenylenebis(3-(chlorodiazenyl)-6-methyl-1H-pyrazolo[3,4-b]-pyridine-4,5-diyl))bis(ethan-1-one) (4) respectively. On the other hand, reaction of 4 with malononitrile, 2-cyanoethanethioamide, ethyl acetoacetate, acetyl acetone, ethyl benzoylacetate, diethylmalonate, ethyl cyanoacetate and phenacylbromide aiming to build up pyrazolotriazine or pyrazole ring on the ring system of 4. Structures of all newly synthesized heterocyclic compounds in the present study were confirmed by considering the data of IR, 1H NMR, mass spectra as well as that of elemental analyses.
文摘The positive effect of levodopa in the treatment of Parkinson’s disease,although it is limited in time and has severe side effects,has encouraged the scientific community to look for new drugs that can stop the neurodegenerative process or even regenerate the neuromelanin-containing dopaminergic nigrostriatal neurons.Successful preclinical studies with coenzyme Q10,mitoquinone,isradipine,nilotinib,TCH346,neurturin,zonisamide,deferiprone,prasinezumab,and cinpanemab prompted clinical trials.However,these failed and after more than 50 years levodopa continues to be the key drug in the treatment of the disease,despite its severe side effects after 4–6 years of chronic treatment.The lack of translated successful results obtained in preclinical investigations based on the use of neurotoxins that do not exist in the human body as new drugs for Parkinson’s disease treatment is a big problem.In our opinion,the cause of these failures lies in the experimental animal models involving neurotoxins that do not exist in the human body,such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and 6-hydroxydopamine,that induce a very fast,massive and expansive neurodegenerative process,which contrasts with the extremely slow one of neuromelanin-containing dopaminergic neurons.The exceedingly slow progress of the neurodegenerative process of the nigrostriatal neurons in idiopathic Parkinson’s patients is due to(i)a degenerative model in which the neurotoxic effect of an endogenous neurotoxin affects a single neuron,(ii)a neurotoxic event that is not expansive and(iii)the fact that the neurotoxin that triggers the neurodegenerative process is produced inside the neuromelanin-containing dopaminergic neurons.The endogenous neurotoxin that fits this degenerative model involving one single neuron at a time is aminochrome,since it(i)is generated within neuromelanin-containing dopaminergic neurons,(ii)does not cause an expansive neurotoxic effect and(iii)triggers all the mechanisms involved in the neurodegenerative process of the nigrostriatal neurons in idiopathic Parkinson’s disease.In conclusion,based on the hypothesis that the neurodegenerative process of idiopathic Parkinson’s disease corresponds to a single-neuron neurodegeneration model,we must search for molecules that increase the expression of the neuroprotective enzymes DT-diaphorase and glutathione transferase M2-2.It has been observed that the activation of the Kelch-like ECH-associated protein 1/nuclear factor(erythroid-derived 2)-like 2 pathway is associated with the transcriptional activation of the DT-diaphorase and glutathione transferase genes.
基金National Nature Science Foundation of China(NO.20172007).
文摘Aim To investigate the alkylation of 2-thiopyrimidine. Methods Treating the starting material 2-thiopyrimidine with chloromethyl ethers via a procedure of K2CO3 in DMF or with alkyl halide in CH3ONa-CH3OH at room temperature, to obtain the corresponding regioselective 2-S-allkyl pyrimidines. The products were determined by JH NMR, 2D NMR, IR and MS spectra. Results 2-S-alkyl-pyrimidines were regioselectively synthesized. Conclusion In different conditions with different alkyl halides, 2- thiouracil could be converted into the corresponding 2-S-alkylpyrimidines regioselectively.
基金Project supported by the National Natural Science Foundation of China （Nos. 20272065 and 50125310）, 863 （No. 90101013）, 973 （Nos. 2002AA324080 and 2002CB613405） Program of China. Dedicated to Professor Xikui Jiang on the occasion of his 80th birthday.
文摘In the interest of driving down the cost of DCM-type light emitting materials, we have found a new approach to prepare 2-（t-butyl）-6-methy1-4H-pyrone, which is cost effective and more amenable to large scale production than the reported method. Furthermore, three new DCM-type dyes, N,N-bis-[p-（2-（4-dicyanomethylene-6-t-butyl-4H- pyran-2-yl）-vinyl）-phenyl]-4-t-butyl-aniline （BDCM-BA）, N,N-bis-[p-（2-（4-dicyanomethylene-6-t-butyl-4H-pyran- 2-yl）-vinyl）-phenyl]aniline （BDCM-A） and N,N-bis-[p-（2-（4-dicyanomethylene-6-t-butyl-4H-pyran-2-yl）-vinyl）- phenyl]-4-methoxyl-aniline （BDCM-MA） were synthesized in good yields using 2-（t-butyl）-6-methyl-4H-pyrone as starting material. They can be utilized in OLEDs as nondoped red emitting materials as the result of the restricted concentration quenching effect.
文摘3-（4-Hydroxyphenyl）-4-methyl-6-methoxy-7-hydroxycoumarin （2a） and its analogues with different substituents at the p-position of 3-phenyl group were designed and synthesized as the non-steroidal analogues of 2-methoxyestradiol （2-ME 1）. The desired compounds were synthesized via a novel and simple route and the effects of specific substituents on their antiangiogenesis activities were investigated with Human umbilical vein endothelial cells （HUVECs） proliferation assays. Preliminary biological screening showed that compounds 2a and 2d （IC50 = 61.0 and 76.7 ktM, respectively） have potential anti-angiogenesis activities. The bulk of the group at the p-position of 3-phenyl group likely play an important role in their activities.
基金partially supported by the fund of Key Laboratory of Marine Drugs(0cean University of China),Ministry of Education[KLMD(0UC)2004]by the National Natural Science Foundation of China(No.30530080)+1 种基金A program supported by the Department of Science and Technology of Shandong Province(No.2006GG2205023)by the Guangdong Key Laboratory of Marine Materia Medica is also gratefully acknowledged.
文摘Cultivation of an endophytic fungus Aspergillus niger EN-13 that was isolated from the inner tissue of the marine brown alga Colpomenia sinuosa resulted in the characterization of a new naphthoquinoneimine derivative, namely, 5,7-dihydroxy-2-[1-（4- methoxy-6-oxo-6H-pyran-2-yl）-2-phenylethylamino]-[ 1,4]naphthoquinone. The structure of the new compound was established on the basis of various NMR spectroscopic analyses including 2D NMR techniques, El-MS, and HR-ESI-MS. This compound displayed moderate antifungal activity.
基金supported by national 863 project(Grant No.2004AA625030,2001AA620503)NNSFC(Grant No.20432030)Key Innovative Project of the Academy(Grant No.KZCX3-SW-215).
文摘A new halogenated biindole and a new apo-carotenone have been isolated from the ethanolic extract of the green alga Chaetomorpha basiretorsa Sethcell. On the basis of chemical and spectroscopic methods including 2D NMR technique, their structures have been elucidated as 4,4′-dichloro-5,5′-dibromo-7,7′-dimethoxy-2,2′-bi-1H-indole and 1′S*,4′R*-8-(4′-hydroxy-2′,6′,6′- trimethylcyclohex-2-enyl)-6-methyloct-3E,5E,7E-trien-2-one, respectively.
基金a grant from Shandong Provincial Education Department, No. J08LH54
文摘The present study observed the action of 1H-indole-2, 3-dione （isatin） on Bax protein expression in the substantia nigra of a Parkinson＇s disease animal model. Parkinson＇s disease-like behaviors were induced in C57BL/6J mice treated with 1-methyl-4-phenyl-1,2, 3, 6-tetrahydropyridine （MPTP） Bax protein expression was significantly reduced in isatin （100, 200 mg/kg）-pretreated mice. Results demonstrate that isatin plays a neuroprotective role in mice treated with MPTP by down-regulating Bax protein expression.
基金supported by the National 863 program of China(2003AA2Z3507)Science and Technology Developping Foundation of Shanghai(02DZ19147,01DJ19010)
文摘A new bisxanthone, named bijaponicaxanthone C, was isolated from the whole plant of Hypericum japonicum. The structure was elucidated as 6-[1’’,5’’,6’’-trihydroxy-2’’’-(β-hydroxy-β- methylethyl)-2’’’,3’’’-dihydrofuran(5’’’,4’’’,3’’,4’’)xanthone-3’’’-oxyl]-1,3,5-trihydroxy-4-isoprenylxant- hone (1) on the basis of the spectral and chemical evidences.
