A stereocontrolled construction of the side chain of brassinclide and homobrassinolide has been achieved via the tandem vicinal dialkylation of the pyranone moiety as a key step.
4,4-Dialkyl-2-oxazolin-5-ones are prepared by one step reaction of 2-oxazolin-5-one with the magnesium methyl carbonate(MMC)and alkyIhalides.It is a novel and convenient method for synthesis of α, Υ-disubstitutcd α...4,4-Dialkyl-2-oxazolin-5-ones are prepared by one step reaction of 2-oxazolin-5-one with the magnesium methyl carbonate(MMC)and alkyIhalides.It is a novel and convenient method for synthesis of α, Υ-disubstitutcd α-amino acid by hydrolysis of 4,4-dialkyl-2-oxazolin-5-ones.展开更多
A stereocontrolled construction of the side chain of brassinosteroid was developed via the separated dialkylation and the tandem dialkylation of the pyranone moiety as the key step.
青海湖晚第四纪的古环境演化和湖面变化是学术界长期关注的热点问题,争议也较多。我们对青海湖地区种羊场(ZYC)剖面(120 cm厚)全新世风尘堆积的GDGTs (甘油二烷基甘油四醚)化合物相关指标的古环境意义进行了初步研究,以期从一...青海湖晚第四纪的古环境演化和湖面变化是学术界长期关注的热点问题,争议也较多。我们对青海湖地区种羊场(ZYC)剖面(120 cm厚)全新世风尘堆积的GDGTs (甘油二烷基甘油四醚)化合物相关指标的古环境意义进行了初步研究,以期从一个新的角度对上述问题进行探讨。研究结果表明:1) ZYC剖面的TEX86(由86个碳原子组成的四醚指标)与磁化率正相关,而Ri/b比值(类异戊二烯GDGTs与支链GDGTs丰度的比值)与磁化率负相关。2) ZYC剖面的TEX86指标与湖泊岩芯胖真星介(Eucypris inflata)壳体δ18O指示的7月古水温及长链烯酮(U37K)指示的夏季古水温变化具有相似的变化特征,显示TEX86指标较可靠地指示了青海湖地区的大气温度变化。然而,ZYC剖面的MBT (甲基化指数)和CBT (环化指数)指标在重建古气温方面具有一定的局限性,可能与青海湖地区全新世出现的干旱环境有关。3) ZYC剖面的Ri/b比值与湖泊岩芯E.inflata壳体Sr/Ca比值指示的青海湖湖水的古盐度具有较一致的变化特征,表明Ri/b比值较有效地指示了青海湖地区环境的干湿状况。4) TEX86和Ri/b指标揭示青海湖区在9.5~7.5 ka B.P.为冷干时期;7.5~5.5 ka B.P.为独特的温干阶段,温度在6.2 ka B.P.左右达到最高值;5.5~1.7 ka B.P.为温湿时期;1.7~0 ka B.P.为冷干时期。5)风尘堆积的GDGTs记录表明:7.5~5.5 ka B.P.由于环境干旱,青海湖不太可能出现高湖面;5.5~1.7 ka B.P.由于环境湿润,青海湖很可能出现全新世高湖面;1.7 ka B.P.以来,青海湖地区的气候快速变干。展开更多
Puerarin,an isoflavone compound,is the bioactive component of traditional Chinese medicine.A novel dialkyl puerarin-7-yl phosphate was synthesized and investigated by positive ion electrospray ionization ion trap mass...Puerarin,an isoflavone compound,is the bioactive component of traditional Chinese medicine.A novel dialkyl puerarin-7-yl phosphate was synthesized and investigated by positive ion electrospray ionization ion trap mass spectrometry (ESI MS)in conjunction with tandem mass spectrometry.The fragmentation pathways of dialkyl puerarin-7-yl phosphates were investigated.展开更多
A new synthesis of spirocyclic oxindole analogue spiro[piperidine-4,3'-pyrrolol2,3-b]pyridin]-2'(1'H)-one 1 is described. The key steps involve dialkylation of arylacetonitrile and cyclization of the azaoxindole ...A new synthesis of spirocyclic oxindole analogue spiro[piperidine-4,3'-pyrrolol2,3-b]pyridin]-2'(1'H)-one 1 is described. The key steps involve dialkylation of arylacetonitrile and cyclization of the azaoxindole ring by an intramolecular Buchwald-Hartwig amidation of carboxylic amide and aryl chloride. A small library was obtained by reductive amination of 1 with various aldehydes and was screened against human lung cancer cell A549, human liver cancer cell BEL7402, and human colon cancer cell HCT-8. The results show that most of the library compounds 2 have some inhibitory activities. 2-(Trifluoromethoxy) benzylic substituted spirocyclic azaoxindole 2e was identified as a nanomolar inhibitor against human lung cancer cell A-549 (IC50 = 50 nmol/L).展开更多
We investigated the occurrence and distribution of terrestrial-derived hydroxylated isoprenoid glycerol dialkyl glycerol tetraethers(OH-GDGTs) in the Han River system and their potential impact on the application of t...We investigated the occurrence and distribution of terrestrial-derived hydroxylated isoprenoid glycerol dialkyl glycerol tetraethers(OH-GDGTs) in the Han River system and their potential impact on the application of the ring index of OH-GDGTs(RI-OH) as a sea surface temperature(SST) proxy in the eastern Yellow Sea. Thereby, we analyzed various samples collected along the Han River and from its surrounding areas(South Korea, n = 34). The OHGDGTs were found in all samples investigated. OH-GDGT-0 was the dominant OH-GDGT component in the estuary and marine samples while OH-GDGT-2 was generally dominant in the soils, the lake sediments and the river suspended particulate matter(SPM). Our results thus suggests a possible warm bias of the RI-OH-derived summer SSTs in the coastal zone to which a large amount of terrestrial organic matter is being supplied. Further studies are necessary to better assess the applicability of the RI-OH proxy in the eastern Yellow Sea.展开更多
A facile one-pot synthesis of 3,4,5-substituted furan-2(5H)-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using t...A facile one-pot synthesis of 3,4,5-substituted furan-2(5H)-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed.展开更多
Acetalation of formaldehyde(HCHO)with dialkyl formal or aliphatic alcohol to prepare polyoxymethylene dialkyl ethers(RO(CH2O)nR,n≥1)catalyzed by Br?nsted‐acidic ionic liquids has been developed.The correlation betwe...Acetalation of formaldehyde(HCHO)with dialkyl formal or aliphatic alcohol to prepare polyoxymethylene dialkyl ethers(RO(CH2O)nR,n≥1)catalyzed by Br?nsted‐acidic ionic liquids has been developed.The correlation between the structure and acidity activity of various ionic liquids was studied.Among the ionic liquids investigated,1‐(4‐sulfonic acid)butyl‐3‐methylimidazolium hydrogen sulfate([MIMBs]HSO4)exhibited the best catalytic performance in the reaction of diethoxymethane(DEM1)with trioxane.The influences of ionic liquid loading,molar ratio of DEM1to HCHO,reaction temperature,pressure,time,and reactant source on the catalytic reaction were explored using[MIMBs]HSO4as the catalyst.Under the optimal conditions of n([MIMBs]HSO4):n(DEM1):n(HCHO)=1:80:80,140°C,and4h,the conversion of HCHO and selectivity for DEM2?8were92.6%and95.1%,respectively.The[MIMBs]HSO4catalyst could be easily separated and reused.A feasible mechanism for the catalytic performance of[MIMBs]HSO4was proposed.展开更多
A simple synthesis of highly functionalized 2,5-diaminofurans based pyrimidine derivatives from 1-(carboxymethyl)uracil via a multi-component reaction is described. The reactive 1:1 intermediate produced from the r...A simple synthesis of highly functionalized 2,5-diaminofurans based pyrimidine derivatives from 1-(carboxymethyl)uracil via a multi-component reaction is described. The reactive 1:1 intermediate produced from the reaction of tert-butyl isocyanide and dialkyl acetylenedicarboxylates was trapped at room temperature by 1-(carboxymethyl)uracil derivatives to yield polyfunctio- nalized furan rings in fairly good yields.展开更多
Isoprenoidal glycerol dialkyl glycerol tetraethers (iGDGTs) from the Gulu hot springs (23--83.6 ℃, pH 〉 7) and Yangbajing hot springs (80-128 ℃, pH 〉 7) were analyzed in order to investigate the distribution...Isoprenoidal glycerol dialkyl glycerol tetraethers (iGDGTs) from the Gulu hot springs (23--83.6 ℃, pH 〉 7) and Yangbajing hot springs (80-128 ℃, pH 〉 7) were analyzed in order to investigate the distribution of archaeal lipids among different hot springs in Tibet. A soil sample from Gulu was incubated at different temperatures and analyzed for changes in iGDGTs to help evaluate whether surrounding soil may contribute to the iGDGTs in hot springs. The sources of bacterial GDGTs (bGDGTs) in these hot springs were also investigated. The results revealed different profiles ofiGDGTs between Gulu and Yangbajing hot springs. Core iGDGTs and polar iGDGTs also presented different patterns in each hot spring. The PCA analysis showed that the structure of polar iGDGTs can be explained by three factors and suggested multiple sources of these compounds. Bivariate correlation analysis showed significant positive correlations between polar and core bGDGTs, suggesting the in situ production of bGDGTs in the hot springs. Furthermore, in the soil incubation experiment, temperature had the most significant influence on concentration of bGDGTs rather than iGDGTs, and polar bGDGTs had greater variability than core bGDGTs with changing temperature. Our results indicated that soil input had little influence on the composition of GDGTs in Tibetan hot springs.展开更多
Langmuir films behavior of asymmetric glycerol dialkyl nonitol tetraether (GDNT) lipids at the air-water interface (temperature 19℃ ± 1℃) investigated the stability of the mean ratio of Langmuir films for diffe...Langmuir films behavior of asymmetric glycerol dialkyl nonitol tetraether (GDNT) lipids at the air-water interface (temperature 19℃ ± 1℃) investigated the stability of the mean ratio of Langmuir films for different spreading time prior to the transfer film. Floating monolayer films stability is an important parameter to obtain high-quality Langmuir-Blodgett films for their aplications. Hysteresis loop of the compression-decompression (μ-A) isotherms of Langmuir film GDNT used to analyze the thermodynamic stability of the monolayer films and its features. Langmuir films stability of tetraether lipid GDNT shown more stable at the time of spreading longer than a short time.展开更多
An expedient,synthetic method to fused polycyclic derivatives of isoquinoline is described via tandem reaction of isoquinoline,dialkyl acetylenedicarboxylates and dialkyl chloromalonate.
An efficient synthesis of thiazines from the three component reactions between dialkyl acetylenedicarboxylates, arylisothio- cyanates and N-nucleophiles at room temperature in water as the solvent is described.
The addition of pyridine-2-carboxaldoxime or α-furildioxime to dialkyl acety lenedicarboxy lates under neutral conditions in the presence of alkyl isocyanides leads to ketenimines and bis(ketenimines) in good yields.
A mild and simple method for the synthesis of dialkyl chlorophosphates is described, bis(trichloromethyl) carbonate (BTC) is used as the effective reagent for the conversion of dialkyl phosphites to their correspo...A mild and simple method for the synthesis of dialkyl chlorophosphates is described, bis(trichloromethyl) carbonate (BTC) is used as the effective reagent for the conversion of dialkyl phosphites to their corresponding dialkyl chlorophosphates under mild conditions.展开更多
A simple and efficient synthetic protocol has been developed using a one-pot multicomponent reaction (MCR) involving 2-aminophenols, dialkyl acetylenedicarboxylates, and ethyl bromopyruvate in poly(ethyleneglycol)...A simple and efficient synthetic protocol has been developed using a one-pot multicomponent reaction (MCR) involving 2-aminophenols, dialkyl acetylenedicarboxylates, and ethyl bromopyruvate in poly(ethyleneglycol). This protocol was utilized to prepare novel pyrrolo[2,1-c][1,4]benzoxazines in excellent yields.展开更多
Three-component reaction of arylsulfonamides,dialkyl acetylenedicarboxylates,and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-(ary...Three-component reaction of arylsulfonamides,dialkyl acetylenedicarboxylates,and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-(arylsulfonyl)-4-ethoxy-5-oxo-2,5-dihydro -1H-pyrolle-2,3-dicarboxylates in good yields.展开更多
A novel and efficient procedure for the synthesis of alkyl phosphonates through one pot condensation of alkyl halide and trialkyl /aryl phosphite in the presence of Amberlyst-15 as catalyst under solvent free conditio...A novel and efficient procedure for the synthesis of alkyl phosphonates through one pot condensation of alkyl halide and trialkyl /aryl phosphite in the presence of Amberlyst-15 as catalyst under solvent free conditions was applied.It demonstrated several advantages such as good yields of products,simple operation,convenient separation and inexpensive catalyst.展开更多
Isoquinoline reacts with dialkyl acetylenedicarboxylates in the presence of kojic acid or8-hydroxyquinoline to generate 1,2-dihydroisoquinoline derivatives. The simplicity, mild reaction conditions and high yields of ...Isoquinoline reacts with dialkyl acetylenedicarboxylates in the presence of kojic acid or8-hydroxyquinoline to generate 1,2-dihydroisoquinoline derivatives. The simplicity, mild reaction conditions and high yields of products make it an interesting process compared to other approaches. The compounds have been analyzed for antibacterial activity against Gram negative and Gram positive bacteria. The results indicated that 1,2-dihydroisoquinolines derived from kojic acid are effective against all of the studied bacteria especially against Bacillus subtilis, while the products obtained from8-hydroxyquinoline are active only against Gram positive bacteria.展开更多
文摘A stereocontrolled construction of the side chain of brassinclide and homobrassinolide has been achieved via the tandem vicinal dialkylation of the pyranone moiety as a key step.
文摘4,4-Dialkyl-2-oxazolin-5-ones are prepared by one step reaction of 2-oxazolin-5-one with the magnesium methyl carbonate(MMC)and alkyIhalides.It is a novel and convenient method for synthesis of α, Υ-disubstitutcd α-amino acid by hydrolysis of 4,4-dialkyl-2-oxazolin-5-ones.
文摘A stereocontrolled construction of the side chain of brassinosteroid was developed via the separated dialkylation and the tandem dialkylation of the pyranone moiety as the key step.
文摘青海湖晚第四纪的古环境演化和湖面变化是学术界长期关注的热点问题,争议也较多。我们对青海湖地区种羊场(ZYC)剖面(120 cm厚)全新世风尘堆积的GDGTs (甘油二烷基甘油四醚)化合物相关指标的古环境意义进行了初步研究,以期从一个新的角度对上述问题进行探讨。研究结果表明:1) ZYC剖面的TEX86(由86个碳原子组成的四醚指标)与磁化率正相关,而Ri/b比值(类异戊二烯GDGTs与支链GDGTs丰度的比值)与磁化率负相关。2) ZYC剖面的TEX86指标与湖泊岩芯胖真星介(Eucypris inflata)壳体δ18O指示的7月古水温及长链烯酮(U37K)指示的夏季古水温变化具有相似的变化特征,显示TEX86指标较可靠地指示了青海湖地区的大气温度变化。然而,ZYC剖面的MBT (甲基化指数)和CBT (环化指数)指标在重建古气温方面具有一定的局限性,可能与青海湖地区全新世出现的干旱环境有关。3) ZYC剖面的Ri/b比值与湖泊岩芯E.inflata壳体Sr/Ca比值指示的青海湖湖水的古盐度具有较一致的变化特征,表明Ri/b比值较有效地指示了青海湖地区环境的干湿状况。4) TEX86和Ri/b指标揭示青海湖区在9.5~7.5 ka B.P.为冷干时期;7.5~5.5 ka B.P.为独特的温干阶段,温度在6.2 ka B.P.左右达到最高值;5.5~1.7 ka B.P.为温湿时期;1.7~0 ka B.P.为冷干时期。5)风尘堆积的GDGTs记录表明:7.5~5.5 ka B.P.由于环境干旱,青海湖不太可能出现高湖面;5.5~1.7 ka B.P.由于环境湿润,青海湖很可能出现全新世高湖面;1.7 ka B.P.以来,青海湖地区的气候快速变干。
文摘Puerarin,an isoflavone compound,is the bioactive component of traditional Chinese medicine.A novel dialkyl puerarin-7-yl phosphate was synthesized and investigated by positive ion electrospray ionization ion trap mass spectrometry (ESI MS)in conjunction with tandem mass spectrometry.The fragmentation pathways of dialkyl puerarin-7-yl phosphates were investigated.
基金supported by the program of research fund for returning scholars of Ministry of Education of China(No.200812)the Open Foundation of Chemical Engineering Subject(No.200903),Qingdao University of Science & Technology,China
文摘A new synthesis of spirocyclic oxindole analogue spiro[piperidine-4,3'-pyrrolol2,3-b]pyridin]-2'(1'H)-one 1 is described. The key steps involve dialkylation of arylacetonitrile and cyclization of the azaoxindole ring by an intramolecular Buchwald-Hartwig amidation of carboxylic amide and aryl chloride. A small library was obtained by reductive amination of 1 with various aldehydes and was screened against human lung cancer cell A549, human liver cancer cell BEL7402, and human colon cancer cell HCT-8. The results show that most of the library compounds 2 have some inhibitory activities. 2-(Trifluoromethoxy) benzylic substituted spirocyclic azaoxindole 2e was identified as a nanomolar inhibitor against human lung cancer cell A-549 (IC50 = 50 nmol/L).
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIP)(No.NRF-2016R1A2B3015388)
文摘We investigated the occurrence and distribution of terrestrial-derived hydroxylated isoprenoid glycerol dialkyl glycerol tetraethers(OH-GDGTs) in the Han River system and their potential impact on the application of the ring index of OH-GDGTs(RI-OH) as a sea surface temperature(SST) proxy in the eastern Yellow Sea. Thereby, we analyzed various samples collected along the Han River and from its surrounding areas(South Korea, n = 34). The OHGDGTs were found in all samples investigated. OH-GDGT-0 was the dominant OH-GDGT component in the estuary and marine samples while OH-GDGT-2 was generally dominant in the soils, the lake sediments and the river suspended particulate matter(SPM). Our results thus suggests a possible warm bias of the RI-OH-derived summer SSTs in the coastal zone to which a large amount of terrestrial organic matter is being supplied. Further studies are necessary to better assess the applicability of the RI-OH proxy in the eastern Yellow Sea.
基金fnancial support from the Research Council of the University of Sistan and Baluchestan
文摘A facile one-pot synthesis of 3,4,5-substituted furan-2(5H)-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed.
基金supported by the National Natural Science Foundation of China(21473225)~~
文摘Acetalation of formaldehyde(HCHO)with dialkyl formal or aliphatic alcohol to prepare polyoxymethylene dialkyl ethers(RO(CH2O)nR,n≥1)catalyzed by Br?nsted‐acidic ionic liquids has been developed.The correlation between the structure and acidity activity of various ionic liquids was studied.Among the ionic liquids investigated,1‐(4‐sulfonic acid)butyl‐3‐methylimidazolium hydrogen sulfate([MIMBs]HSO4)exhibited the best catalytic performance in the reaction of diethoxymethane(DEM1)with trioxane.The influences of ionic liquid loading,molar ratio of DEM1to HCHO,reaction temperature,pressure,time,and reactant source on the catalytic reaction were explored using[MIMBs]HSO4as the catalyst.Under the optimal conditions of n([MIMBs]HSO4):n(DEM1):n(HCHO)=1:80:80,140°C,and4h,the conversion of HCHO and selectivity for DEM2?8were92.6%and95.1%,respectively.The[MIMBs]HSO4catalyst could be easily separated and reused.A feasible mechanism for the catalytic performance of[MIMBs]HSO4was proposed.
基金supported by the Research Council of the University of Mazandaran,Iran
文摘A simple synthesis of highly functionalized 2,5-diaminofurans based pyrimidine derivatives from 1-(carboxymethyl)uracil via a multi-component reaction is described. The reactive 1:1 intermediate produced from the reaction of tert-butyl isocyanide and dialkyl acetylenedicarboxylates was trapped at room temperature by 1-(carboxymethyl)uracil derivatives to yield polyfunctio- nalized furan rings in fairly good yields.
基金supported by the National Natural Science Foundation of China(Grant No.40972211)the US National Science Foundation(Grant Nos.ETBC-1024614 and OISE- 0968421 )
文摘Isoprenoidal glycerol dialkyl glycerol tetraethers (iGDGTs) from the Gulu hot springs (23--83.6 ℃, pH 〉 7) and Yangbajing hot springs (80-128 ℃, pH 〉 7) were analyzed in order to investigate the distribution of archaeal lipids among different hot springs in Tibet. A soil sample from Gulu was incubated at different temperatures and analyzed for changes in iGDGTs to help evaluate whether surrounding soil may contribute to the iGDGTs in hot springs. The sources of bacterial GDGTs (bGDGTs) in these hot springs were also investigated. The results revealed different profiles ofiGDGTs between Gulu and Yangbajing hot springs. Core iGDGTs and polar iGDGTs also presented different patterns in each hot spring. The PCA analysis showed that the structure of polar iGDGTs can be explained by three factors and suggested multiple sources of these compounds. Bivariate correlation analysis showed significant positive correlations between polar and core bGDGTs, suggesting the in situ production of bGDGTs in the hot springs. Furthermore, in the soil incubation experiment, temperature had the most significant influence on concentration of bGDGTs rather than iGDGTs, and polar bGDGTs had greater variability than core bGDGTs with changing temperature. Our results indicated that soil input had little influence on the composition of GDGTs in Tibetan hot springs.
文摘Langmuir films behavior of asymmetric glycerol dialkyl nonitol tetraether (GDNT) lipids at the air-water interface (temperature 19℃ ± 1℃) investigated the stability of the mean ratio of Langmuir films for different spreading time prior to the transfer film. Floating monolayer films stability is an important parameter to obtain high-quality Langmuir-Blodgett films for their aplications. Hysteresis loop of the compression-decompression (μ-A) isotherms of Langmuir film GDNT used to analyze the thermodynamic stability of the monolayer films and its features. Langmuir films stability of tetraether lipid GDNT shown more stable at the time of spreading longer than a short time.
基金Sanandaj Branch, Islamic Azad University Research Council for the fnancial support of this research
文摘An expedient,synthetic method to fused polycyclic derivatives of isoquinoline is described via tandem reaction of isoquinoline,dialkyl acetylenedicarboxylates and dialkyl chloromalonate.
文摘An efficient synthesis of thiazines from the three component reactions between dialkyl acetylenedicarboxylates, arylisothio- cyanates and N-nucleophiles at room temperature in water as the solvent is described.
文摘The addition of pyridine-2-carboxaldoxime or α-furildioxime to dialkyl acety lenedicarboxy lates under neutral conditions in the presence of alkyl isocyanides leads to ketenimines and bis(ketenimines) in good yields.
基金the National Basic Research Program of China 973 Program(No.2003CB114400)the National Natural Science Foundation of China(No.20476098)for financial support.(No.20676123)
文摘A mild and simple method for the synthesis of dialkyl chlorophosphates is described, bis(trichloromethyl) carbonate (BTC) is used as the effective reagent for the conversion of dialkyl phosphites to their corresponding dialkyl chlorophosphates under mild conditions.
基金Sanandaj Branch,Islamic Azad University Research Council for the financial support
文摘A simple and efficient synthetic protocol has been developed using a one-pot multicomponent reaction (MCR) involving 2-aminophenols, dialkyl acetylenedicarboxylates, and ethyl bromopyruvate in poly(ethyleneglycol). This protocol was utilized to prepare novel pyrrolo[2,1-c][1,4]benzoxazines in excellent yields.
基金the financial support from the Research Council of Islamic Azad University,Mahshahr Branch
文摘Three-component reaction of arylsulfonamides,dialkyl acetylenedicarboxylates,and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-(arylsulfonyl)-4-ethoxy-5-oxo-2,5-dihydro -1H-pyrolle-2,3-dicarboxylates in good yields.
基金BRNS.BARC,Mumbai for providing financial assistance(2010/37C/26/BRNS/1424)
文摘A novel and efficient procedure for the synthesis of alkyl phosphonates through one pot condensation of alkyl halide and trialkyl /aryl phosphite in the presence of Amberlyst-15 as catalyst under solvent free conditions was applied.It demonstrated several advantages such as good yields of products,simple operation,convenient separation and inexpensive catalyst.
文摘Isoquinoline reacts with dialkyl acetylenedicarboxylates in the presence of kojic acid or8-hydroxyquinoline to generate 1,2-dihydroisoquinoline derivatives. The simplicity, mild reaction conditions and high yields of products make it an interesting process compared to other approaches. The compounds have been analyzed for antibacterial activity against Gram negative and Gram positive bacteria. The results indicated that 1,2-dihydroisoquinolines derived from kojic acid are effective against all of the studied bacteria especially against Bacillus subtilis, while the products obtained from8-hydroxyquinoline are active only against Gram positive bacteria.