The configuration of the hydroxy acid 2, a product from base-catalyzed autoxidation of 3α,5-cyclo-5α-cholestane-6-one,was established on the basis of NMR techniques and the mechanism of the formation of 2 was discus...The configuration of the hydroxy acid 2, a product from base-catalyzed autoxidation of 3α,5-cyclo-5α-cholestane-6-one,was established on the basis of NMR techniques and the mechanism of the formation of 2 was discussed.展开更多
A study was conducted to improve 9-methoxycanthin-6-one productivity （potential anti-tumour compound） from callus cultures of Emycorna longifolia （Tongkat All）. Several factors affecting 9-methoxycanthin-6-one pro...A study was conducted to improve 9-methoxycanthin-6-one productivity （potential anti-tumour compound） from callus cultures of Emycorna longifolia （Tongkat All）. Several factors affecting 9-methoxycanthin-6-one production in callus cultures such as different medium compositions and physical factors were investigated and analyzed. Results show that a higher production of 9-methoxycanthin-6-one （3.84 mg-g-1 DW （Dry Weight）） is obtained from callus cultured in 1/4 MS basal media. At fructose of 2% （w/v）, the production of 9-methoxycanthin-6-one （4.59 mgg-1DW） is promoted to gain the highest yield, compared to other carbon sources tested. The addition of 2.0-mg·L^-1 dicamba also increases 9-methoxycanthin-6-one production （12.3 mg·g^-1 DW）. Higher production of 9-methoxycanthin-6-one was obtained at pH 5.5 （1.53 mg·g^-1 DW）. Production of 9-methoxycanthin-6-one （2.34 mg-g^-1 DW） in callus cultures is also increased when the medium is added with 1×10 ^-1μM phenylalanine. This study suggests that the successful production of 9-methoxycanthin-6-one in vitro cultures has a potential in large-scale production using bioreactor technology.展开更多
ABSTRACT Ethyl 3,9-dimethyl-7-phenyl-6It-dibenzo[b,d]pyran-6-one-8-carboxylate （C24H20O4, Mr = 372.40） has been synthesized and its structure was determined by ^1H and ^1C NMR, ESI-MS, elemental analysis, and X-ray ...ABSTRACT Ethyl 3,9-dimethyl-7-phenyl-6It-dibenzo[b,d]pyran-6-one-8-carboxylate （C24H20O4, Mr = 372.40） has been synthesized and its structure was determined by ^1H and ^1C NMR, ESI-MS, elemental analysis, and X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/n, with a = 8.3674（11）, b = 10.6683（14）, c = 11.3817（15） A, a = 95.596（2）, β = 109.866（2）, γ = 94.495（2）°, V= 944.2（2）A^3, Z= 2, Dc = 1.310 g/cm3, μ= 0.089 mm^-1, F（000） = 392, R = 0.0482 and wR = 0.1281 for 2916 observed reflections with I 〉 2σ（I）. In the crystal structure, the fused tricyclic nucleus of the title compound is not fully coplanar. Analysis of the crystal packing indicates aromatic π-π stacking interactions occurring between the fused tricyclic aromatic rings of neighboring molecules in which a maximum overlap of the x-electron systems was achieved. Fluorescence and thermal studies indicate that compound 3 has good optical properties and thermal stability.展开更多
Ethyl 3,9-dihydroxy-9-methyl-7-phenyl-7,8,10-trihydro-6H-dibenzo[b,d]pyran-6-one-8-carboxylate（C（23）H（22）O6,Mr = 394.42） has been synthesized and its structure was determined by ~1H and ^（13）C NMR,ESI-MS,eleme...Ethyl 3,9-dihydroxy-9-methyl-7-phenyl-7,8,10-trihydro-6H-dibenzo[b,d]pyran-6-one-8-carboxylate（C（23）H（22）O6,Mr = 394.42） has been synthesized and its structure was determined by ~1H and ^（13）C NMR,ESI-MS,elemental analysis,and X-ray single-crystal diffraction.The crystal belongs to the triclinic system,space group P1,with a = 8.8220（17）,b = 9.881（2）,c = 12.157（2） A,α= 90.488（3）,β= 102.664（4）,γ= 98.799（3）°,V= 1020.8（3） A^3,Z= 2,Dc = 1.342 g/cm^3,μ= 0.099mm^（-1）,F（000） = 436,R = 0.0615 and wR = 0.2501 for 2592 observed reflections with（I2σ（I））.In the crystal structure,the coumarin ring system is planar and the 3：4 fused cyclohexane ring adopts distorted half-chair conformation.Rich hydrogen bonding interactions are formed between compound 2 and lattice water molecules.These interactions assemble molecules of 2 into 2D layered networks in an AB stacking sequence.Its in vitro antiproliferative activities against three human cancer cell lines were evaluated by MTT assay.展开更多
1-substituted-5-benzoylamino-4-pyrazolecarboxamides(2)were prepared by the reaction of 1-substituted pyrazolo[3,4-d]-oxazinone(1) with amines in benzene.The compound 2 was refluxed with excess LiAlH_4 in a mixture of ...1-substituted-5-benzoylamino-4-pyrazolecarboxamides(2)were prepared by the reaction of 1-substituted pyrazolo[3,4-d]-oxazinone(1) with amines in benzene.The compound 2 was refluxed with excess LiAlH_4 in a mixture of THF and ether,one of the two carbamoyl groups in the molecule 2 was reduced selectively.As the results,1-substituted-5- benzylamino-4-pyrazolecarboxamides(3)were obtained.Compounds 3 reacted with Cl_2PPh-X,or P(NET_2)_3,producing the title compounds(4). The conditions of the reactions were studied.展开更多
A novel approach to the synthesis of 6, 7-disubstituted-1H-quinoxalin-2-ones is described.The title compounds were regioselectively prepared by starting from substituted phenylamines andchloroacetyl chloride through t...A novel approach to the synthesis of 6, 7-disubstituted-1H-quinoxalin-2-ones is described.The title compounds were regioselectively prepared by starting from substituted phenylamines andchloroacetyl chloride through the efficient sequence of acylation, nitration, reduction, intramolecular alkylation, and oxidation.展开更多
Preost-Woodward hydroxylation of 2 gave the 22S,23S-glycol(3), contrary to expectation.It is suggested that the formation of the two possible iodonium ions(4a and 4b)are reversible,thus allowing the discriminatory ace...Preost-Woodward hydroxylation of 2 gave the 22S,23S-glycol(3), contrary to expectation.It is suggested that the formation of the two possible iodonium ions(4a and 4b)are reversible,thus allowing the discriminatory acetoxy group to follow the less hindered route,reacting with 4a virtually exclusively.展开更多
A method of synthesis of 4,6-disubstituted 5-thioxo-1,2,4-triazin- 3-ones from benzothioformanilides and semicarbazide is described.And six new compounds were synthesized by this method.
The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi- eudesm-4-en-3-one （1）, a highly complex natural eudesmane, was described.
4,6-Diarylpyrimidin-2(1H)-one derivatives have been synthesized from three-component one-pot condensation of acetophe-none derivatives,aldehydes and urea in the presence of trimethylsilyl chloride and a catalytic amou...4,6-Diarylpyrimidin-2(1H)-one derivatives have been synthesized from three-component one-pot condensation of acetophe-none derivatives,aldehydes and urea in the presence of trimethylsilyl chloride and a catalytic amount of HPMoOunder solvent-free conditions.展开更多
4-Amino-3-mercapto-6-methyl-l,2,4-triazin-5（4H）-one 1 converted to 4-amino-6-methy-3-（methylthio）-1,2,4-triazin-5（4H）-one by methylation with methyl iodide.Controlled hydrazination of the resulting compound affo...4-Amino-3-mercapto-6-methyl-l,2,4-triazin-5（4H）-one 1 converted to 4-amino-6-methy-3-（methylthio）-1,2,4-triazin-5（4H）-one by methylation with methyl iodide.Controlled hydrazination of the resulting compound afforded 4-amino-3-hydrazinyl-6- methyl-l,2,4-triazin-5（4H）-one 2 as a building block,to the synthesis of some novel derivatives of[1,2,4]triazino- [4,3,b][1,2,4,5]tetrazepine 3-6,by the reaction with 3-chloropentane-2,4-dione,chloro acetonitrile,1,3-dichloroacetone,and methyl bromoacetate.This general synthetic procedure can be extended to the preparation of wide variety of tetrazepines using 1,2- bielectrophiles derivatives.展开更多
A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions o...A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions of 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acids 6a-p with polyphosphoric acid (PPA) as catalyst and solvent under mild conditions. The key intermediates 6a-p were prepared through the in situ formation of ethyl 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylates 5a-p followed by hydrolysis with aqueous ethanolic sodium hydroxide solution. The novel synthetic method has the advantages of good yields, easy work-up, and environmentally friendly character, which may provide a novel highly efficient process for making quinoline and related azaheterocycle libraries.展开更多
On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-but...On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-butyl-4'-hydroxy-phenyl)-ethyloxy-p-cresole is produced as result of a structure transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one in a solid phase at room temperature except a single crystal at transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one a new substance is formed too. Spectrums 1Н and 13С NMR differ from similar spectrums of initial compound and the single crystal. New substance represents an admixture of isomeric compounds, capable reversible to be transformed in initial 5,7-di-tert-butylspiro(2,5) octa-4,7-diene-6-one and 2-(3’, 5'-di-tert-butyl-4'-hydroxyphenyl)-ethyloxy-p-cresole.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
A metal-free visible-light-induced synthesis of aza-polycyclic aromatic hydrocarbons via cascade alkylation/cyclization of N-methacryloyl-2-phenylbenzimidazole was developed.The reaction was carried out with inactive ...A metal-free visible-light-induced synthesis of aza-polycyclic aromatic hydrocarbons via cascade alkylation/cyclization of N-methacryloyl-2-phenylbenzimidazole was developed.The reaction was carried out with inactive alkanes and cyclic ethers as alkylation reagents,and phenanthrenequinone(PQ)as a direct hydrogen-atom transfer(HAT)photocatalyst.The desired products were obtained in moderate to good yields at room temperature under air.展开更多
The corrosion inhibition properties of 2,6-diphenylpiperidin-4-one (DPP) (1A) and 2,6-diphenyldihydro-2H-thiopyran-4(3H)-one (DPDT) (1B) for mild steel in 1 M phosphoric acid were studied using weight loss, potentiody...The corrosion inhibition properties of 2,6-diphenylpiperidin-4-one (DPP) (1A) and 2,6-diphenyldihydro-2H-thiopyran-4(3H)-one (DPDT) (1B) for mild steel in 1 M phosphoric acid were studied using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopic techniques. The effect of temperature on the corrosion behavior of mild steel has been examined in the temperature range 303 - 328 K. The inhibition efficiency increases with increasing inhibitor concentration but decreases with increasing temperature. Potentiodynamic polarization studies indicated the mixed nature of inhibitors. The adsorption of the inhibitors on mild steel surface obeyed the Langmuir adsorption isotherms. The density functional theory (DFT) at the B3LYP/6- 31G (d) basis set level was performed on 1A and 1B to investigate the correlation between molecular structure and the corresponding inhibition efficiency (%). The quantum chemical parameters such as EHOMO, ELUMO, the energy gap (E), hardness (η), softness (S), dipole moment (μ), electron affinity (A), ionization potential (I), the absolute electronegativity (χ), the fraction of electron transferred (N), electrophilicity index (ω), the back-donation (EBack-donation) and Mulliken population analysis have been calculated.展开更多
The title compound（ethyl 3-（4-methoxyphenyl）-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylate） has been synthesized,and its crystal structure was characterized by X-ray single-crystal diffraction.The c...The title compound（ethyl 3-（4-methoxyphenyl）-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylate） has been synthesized,and its crystal structure was characterized by X-ray single-crystal diffraction.The crystal belongs to monoclinic,space group P21/n,with a = 10.124（4）,b = 11.754（4）,c = 13.792（5） ,β = 111.533（3）o,V = 1526.6（10） 3,Z = 4,C17H19O6,Mr = 319.32,Dc = 1.389 g/cm3,F（000） = 676,λ（MoKα） = 0.71073 ,μ = 0.105 mm-1,R = 0.0660 and wR = 0.2027 for 2993 observed reflections（I 2σ（I））.The compound shows potent anti-tumor activity in vitro.展开更多
In search for new antioxidant agents derived from 6-azauracil, the spiro-5-(flurin-9’-yl)-6-azauracil <strong>3</strong> and their <em>N</em>,<em>N</em>-disubstituted-6-azauracils ...In search for new antioxidant agents derived from 6-azauracil, the spiro-5-(flurin-9’-yl)-6-azauracil <strong>3</strong> and their <em>N</em>,<em>N</em>-disubstituted-6-azauracils <strong>4</strong> - <strong>17</strong> have been synthesized using various methods and reaction conditions. Structure of the new synthesized compounds was deduced from elemental analysis and spectral measurements, for example IR, 1H/13C NMR and mass spectroscopy. The antioxidant evaluation of the new targets showed that the activity increases in the order of <strong>8</strong> > <strong>10</strong> > <strong>6</strong> > <strong>7</strong> > <strong>9</strong> in comparison with 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and ascorbic acid as standards.展开更多
In this paper,obtainment of 3 by simultaneous inversion of configurations of C_(22),C_(23) in 2 via its ditosylate or dimesylate was unsuccessful,leading to elimination products instead.However, monotosylate of 2 can ...In this paper,obtainment of 3 by simultaneous inversion of configurations of C_(22),C_(23) in 2 via its ditosylate or dimesylate was unsuccessful,leading to elimination products instead.However, monotosylate of 2 can be readily obtained with exclusive regioselectivity,which in turn gave a single epoxide 7b Hydrolysis of 7b gave 3 and 2 is a ratio of 2:1,with a combined yield of 80%.The recovered 2 can of course be recycled again.展开更多
文摘The configuration of the hydroxy acid 2, a product from base-catalyzed autoxidation of 3α,5-cyclo-5α-cholestane-6-one,was established on the basis of NMR techniques and the mechanism of the formation of 2 was discussed.
基金supported by IRPA grant MMBPP-FRIM-03-02-04.(Under Malaysia-Massachucetts of Technology USA,MIT Biotechnology Partnership Program)
文摘A study was conducted to improve 9-methoxycanthin-6-one productivity （potential anti-tumour compound） from callus cultures of Emycorna longifolia （Tongkat All）. Several factors affecting 9-methoxycanthin-6-one production in callus cultures such as different medium compositions and physical factors were investigated and analyzed. Results show that a higher production of 9-methoxycanthin-6-one （3.84 mg-g-1 DW （Dry Weight）） is obtained from callus cultured in 1/4 MS basal media. At fructose of 2% （w/v）, the production of 9-methoxycanthin-6-one （4.59 mgg-1DW） is promoted to gain the highest yield, compared to other carbon sources tested. The addition of 2.0-mg·L^-1 dicamba also increases 9-methoxycanthin-6-one production （12.3 mg·g^-1 DW）. Higher production of 9-methoxycanthin-6-one was obtained at pH 5.5 （1.53 mg·g^-1 DW）. Production of 9-methoxycanthin-6-one （2.34 mg-g^-1 DW） in callus cultures is also increased when the medium is added with 1×10 ^-1μM phenylalanine. This study suggests that the successful production of 9-methoxycanthin-6-one in vitro cultures has a potential in large-scale production using bioreactor technology.
基金supported by grants from the Provincial Key Project of Natural Science Research for Colleges and Universities of Anhui Province(No.20130911160)the Doctoral Foundation of Anhui University of Science and Technology(No.11117)
文摘ABSTRACT Ethyl 3,9-dimethyl-7-phenyl-6It-dibenzo[b,d]pyran-6-one-8-carboxylate （C24H20O4, Mr = 372.40） has been synthesized and its structure was determined by ^1H and ^1C NMR, ESI-MS, elemental analysis, and X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/n, with a = 8.3674（11）, b = 10.6683（14）, c = 11.3817（15） A, a = 95.596（2）, β = 109.866（2）, γ = 94.495（2）°, V= 944.2（2）A^3, Z= 2, Dc = 1.310 g/cm3, μ= 0.089 mm^-1, F（000） = 392, R = 0.0482 and wR = 0.1281 for 2916 observed reflections with I 〉 2σ（I）. In the crystal structure, the fused tricyclic nucleus of the title compound is not fully coplanar. Analysis of the crystal packing indicates aromatic π-π stacking interactions occurring between the fused tricyclic aromatic rings of neighboring molecules in which a maximum overlap of the x-electron systems was achieved. Fluorescence and thermal studies indicate that compound 3 has good optical properties and thermal stability.
基金the financial support from the Natural Science Foundation of Jiangsu University of Technologythe Provincial Key Project of Natural Science Research for Colleges and Universities of Anhui Province(KJ2014A062)
文摘Ethyl 3,9-dihydroxy-9-methyl-7-phenyl-7,8,10-trihydro-6H-dibenzo[b,d]pyran-6-one-8-carboxylate（C（23）H（22）O6,Mr = 394.42） has been synthesized and its structure was determined by ~1H and ^（13）C NMR,ESI-MS,elemental analysis,and X-ray single-crystal diffraction.The crystal belongs to the triclinic system,space group P1,with a = 8.8220（17）,b = 9.881（2）,c = 12.157（2） A,α= 90.488（3）,β= 102.664（4）,γ= 98.799（3）°,V= 1020.8（3） A^3,Z= 2,Dc = 1.342 g/cm^3,μ= 0.099mm^（-1）,F（000） = 436,R = 0.0615 and wR = 0.2501 for 2592 observed reflections with（I2σ（I））.In the crystal structure,the coumarin ring system is planar and the 3：4 fused cyclohexane ring adopts distorted half-chair conformation.Rich hydrogen bonding interactions are formed between compound 2 and lattice water molecules.These interactions assemble molecules of 2 into 2D layered networks in an AB stacking sequence.Its in vitro antiproliferative activities against three human cancer cell lines were evaluated by MTT assay.
基金Project supported by National Natural Science Foundation of China.
文摘1-substituted-5-benzoylamino-4-pyrazolecarboxamides(2)were prepared by the reaction of 1-substituted pyrazolo[3,4-d]-oxazinone(1) with amines in benzene.The compound 2 was refluxed with excess LiAlH_4 in a mixture of THF and ether,one of the two carbamoyl groups in the molecule 2 was reduced selectively.As the results,1-substituted-5- benzylamino-4-pyrazolecarboxamides(3)were obtained.Compounds 3 reacted with Cl_2PPh-X,or P(NET_2)_3,producing the title compounds(4). The conditions of the reactions were studied.
文摘A novel approach to the synthesis of 6, 7-disubstituted-1H-quinoxalin-2-ones is described.The title compounds were regioselectively prepared by starting from substituted phenylamines andchloroacetyl chloride through the efficient sequence of acylation, nitration, reduction, intramolecular alkylation, and oxidation.
文摘Preost-Woodward hydroxylation of 2 gave the 22S,23S-glycol(3), contrary to expectation.It is suggested that the formation of the two possible iodonium ions(4a and 4b)are reversible,thus allowing the discriminatory acetoxy group to follow the less hindered route,reacting with 4a virtually exclusively.
文摘A method of synthesis of 4,6-disubstituted 5-thioxo-1,2,4-triazin- 3-ones from benzothioformanilides and semicarbazide is described.And six new compounds were synthesized by this method.
基金This work was financially supported by the National Natural Science Foundation of China （No 20272021）.
文摘The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi- eudesm-4-en-3-one （1）, a highly complex natural eudesmane, was described.
基金Islamic Azad University of Khorram Abad Council for the financial support
文摘4,6-Diarylpyrimidin-2(1H)-one derivatives have been synthesized from three-component one-pot condensation of acetophe-none derivatives,aldehydes and urea in the presence of trimethylsilyl chloride and a catalytic amount of HPMoOunder solvent-free conditions.
文摘4-Amino-3-mercapto-6-methyl-l,2,4-triazin-5（4H）-one 1 converted to 4-amino-6-methy-3-（methylthio）-1,2,4-triazin-5（4H）-one by methylation with methyl iodide.Controlled hydrazination of the resulting compound afforded 4-amino-3-hydrazinyl-6- methyl-l,2,4-triazin-5（4H）-one 2 as a building block,to the synthesis of some novel derivatives of[1,2,4]triazino- [4,3,b][1,2,4,5]tetrazepine 3-6,by the reaction with 3-chloropentane-2,4-dione,chloro acetonitrile,1,3-dichloroacetone,and methyl bromoacetate.This general synthetic procedure can be extended to the preparation of wide variety of tetrazepines using 1,2- bielectrophiles derivatives.
文摘A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions of 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acids 6a-p with polyphosphoric acid (PPA) as catalyst and solvent under mild conditions. The key intermediates 6a-p were prepared through the in situ formation of ethyl 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylates 5a-p followed by hydrolysis with aqueous ethanolic sodium hydroxide solution. The novel synthetic method has the advantages of good yields, easy work-up, and environmentally friendly character, which may provide a novel highly efficient process for making quinoline and related azaheterocycle libraries.
文摘On an example of spontaneous changes 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one at room temperature, a new example of condensations in a solid station is opened. The single crystal of 2-(3’, 5'-di-tert-butyl-4'-hydroxy-phenyl)-ethyloxy-p-cresole is produced as result of a structure transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one in a solid phase at room temperature except a single crystal at transformation 5,7-di-tert-butylspiro (2,5) octa-4,7-diene-6-one a new substance is formed too. Spectrums 1Н and 13С NMR differ from similar spectrums of initial compound and the single crystal. New substance represents an admixture of isomeric compounds, capable reversible to be transformed in initial 5,7-di-tert-butylspiro(2,5) octa-4,7-diene-6-one and 2-(3’, 5'-di-tert-butyl-4'-hydroxyphenyl)-ethyloxy-p-cresole.
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.
基金supported by the Natural Science Foundation of Xinjiang Uyghur Autonomous Region(Nos.2022E01042,2022TSYCCX0024,and 2021D01E10)the NSFC(Nos.21861036,21961037 and 21762041).
文摘A metal-free visible-light-induced synthesis of aza-polycyclic aromatic hydrocarbons via cascade alkylation/cyclization of N-methacryloyl-2-phenylbenzimidazole was developed.The reaction was carried out with inactive alkanes and cyclic ethers as alkylation reagents,and phenanthrenequinone(PQ)as a direct hydrogen-atom transfer(HAT)photocatalyst.The desired products were obtained in moderate to good yields at room temperature under air.
文摘The corrosion inhibition properties of 2,6-diphenylpiperidin-4-one (DPP) (1A) and 2,6-diphenyldihydro-2H-thiopyran-4(3H)-one (DPDT) (1B) for mild steel in 1 M phosphoric acid were studied using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopic techniques. The effect of temperature on the corrosion behavior of mild steel has been examined in the temperature range 303 - 328 K. The inhibition efficiency increases with increasing inhibitor concentration but decreases with increasing temperature. Potentiodynamic polarization studies indicated the mixed nature of inhibitors. The adsorption of the inhibitors on mild steel surface obeyed the Langmuir adsorption isotherms. The density functional theory (DFT) at the B3LYP/6- 31G (d) basis set level was performed on 1A and 1B to investigate the correlation between molecular structure and the corresponding inhibition efficiency (%). The quantum chemical parameters such as EHOMO, ELUMO, the energy gap (E), hardness (η), softness (S), dipole moment (μ), electron affinity (A), ionization potential (I), the absolute electronegativity (χ), the fraction of electron transferred (N), electrophilicity index (ω), the back-donation (EBack-donation) and Mulliken population analysis have been calculated.
文摘In search for new antioxidant agents derived from 6-azauracil, the spiro-5-(flurin-9’-yl)-6-azauracil <strong>3</strong> and their <em>N</em>,<em>N</em>-disubstituted-6-azauracils <strong>4</strong> - <strong>17</strong> have been synthesized using various methods and reaction conditions. Structure of the new synthesized compounds was deduced from elemental analysis and spectral measurements, for example IR, 1H/13C NMR and mass spectroscopy. The antioxidant evaluation of the new targets showed that the activity increases in the order of <strong>8</strong> > <strong>10</strong> > <strong>6</strong> > <strong>7</strong> > <strong>9</strong> in comparison with 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and ascorbic acid as standards.
文摘In this paper,obtainment of 3 by simultaneous inversion of configurations of C_(22),C_(23) in 2 via its ditosylate or dimesylate was unsuccessful,leading to elimination products instead.However, monotosylate of 2 can be readily obtained with exclusive regioselectivity,which in turn gave a single epoxide 7b Hydrolysis of 7b gave 3 and 2 is a ratio of 2:1,with a combined yield of 80%.The recovered 2 can of course be recycled again.
