RNA modifications have been involved in numerous biological processes, and aberrations of these modifications are tightly associated with various diseases including cancer. Herein, we developed graphenebased solid-pha...RNA modifications have been involved in numerous biological processes, and aberrations of these modifications are tightly associated with various diseases including cancer. Herein, we developed graphenebased solid-phase extraction and robust ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) combined with stable isotope-dilution for simultaneous enrichment and accurate determination of 17 modified nucleosides in human urine. We found graphene could effectively adsorb various modified nucleosides in human urine samples. With this method, we identified and quantified these modified nucleosides in urine samples collected from lung cancer patients and healthy controls.We revealed that the levels of 12 modified nucleosides were all diminished in urine from lung cancer patients, compared with healthy controls. It is worth noting that we demonstrated, for the first time, the presence of 5,2-O-dimethyluridine(m~5U_m) in human urine. Together, we established a robust analytical method for simultaneous determinations of 17 modified nucleosides in human urine, and our results revealed a close correlation between the concentrations of urinary modified nucleosides and the occurrence of lung cancer, implying the potential applications of these modified nucleosides as noninvasive biomarkers for the early detection of lung cancer. Moreover, this study will stimulate future investigations on the regulatory roles of RNA modifications in the initiation and progression of lung cancer.展开更多
Aim: To compare the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia, and to study the effect of humidity and heat on the content of nucleosides. Methods: The contents of nucleos...Aim: To compare the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia, and to study the effect of humidity and heat on the content of nucleosides. Methods: The contents of nucleosides were determined by using high performance capillary electrophoresis (HPCE). Beckman P/ACE System 5010 apparatus equipped with a UV detector and a Beckman untreated fused-silica capillary (57 cm 75 mm, 50 cm effective length) was used. Before sample injection, the capillary was rinsed with 1 molL-1 sodium hydroxide solution and running buffer for 5 min, respectively. A voltage of 20 kV was applied for the separation. Pressure injection was 586 kPa for 6 seconds, and the wavelength of detector was 254 nm. The running time was 20 min at 20 oC. The effect of humidity and heat on the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia was observed for 1, 3, 5 and 10 days at temperature 40 oC, and relative humidity 75%. Results: The content of nucleosides from natural Cordyceps sinensis was higher than that from cultured Cordyceps mycelia. But the contents of nucleosides from freshly collected natural Cordyceps sinensis were very low, even below the limit of quantitation. The contents of nucleosides from natural Cordyceps sinensis were significantly increased by humidity and heat, but this phenomenon was not observed in cultured Cordyceps mycelia. Conclusion: There are differences between the nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia. The nucleosides in natural Cordyceps sinensis may be derived from the degradation of nucleic acids. This implies that adenosine being used for the quality control of natural Cordyceps sinensis may have to be reconsidered.展开更多
Determination of nucleosides and nucleobases is important for the quality control of Fritillaria unibracteata Hsiao et K.C. Hsia var. wabuensis （FUW） due to their physiological and pharmacological actions. In the pr...Determination of nucleosides and nucleobases is important for the quality control of Fritillaria unibracteata Hsiao et K.C. Hsia var. wabuensis （FUW） due to their physiological and pharmacological actions. In the present study, we developed a sensitive and reliable HPLC-diode-array detection method to simultaneously determine ten nucleosides and nucleobases, including cytosine, uracil, cytidine, uridine, thymine, adenine, inosine, guanosine, thymidine and adenosine. Complete separation of all the analytes was achieved on a Zorbax 300 A 300 Extend C18 column with a gradient of methanol-ultrapure water at a flow rate of 1 mL/min in less than 30 min. The diode-array detector wavelength was set at 260 nm for the UV detection of nucleosides and nucleobases. The optimized method provided good linearity （R2〉0.9993 for all the analytes）, satisfactory precision （RSD〈3.715%）, good repeatability （RSD_〈3.748%） and good recovery （RSD from 97.688% to 102.923%）. In addition, the developed method was successfully applied to simultaneous determination of ten nucleosides and nucleobases from FUW, and their content changes of various cultivation time （1-7 years） were further analyzed for the first time. Our findings were useful for ensuring the cultivation time choice of artificial cultivation, quality control, pharmaceutical studies and clinical efficacy of FUW.展开更多
Ganoderma(lingzhi)is a famous herbal medicine and edible supplement in oriental countries for a long history.In this study,a simple micellar electrokinetic chromatography(MEKC)method was established for the analysis o...Ganoderma(lingzhi)is a famous herbal medicine and edible supplement in oriental countries for a long history.In this study,a simple micellar electrokinetic chromatography(MEKC)method was established for the analysis of nucleosides and bases,the major bioactive components in Ganoderma for the first time.By optimizing the borate concentration,the sodium dodecyl sulfate(SDS)concentration and the pH value of running buffer,10 nucleosides and bases achieved an ideal separation.In real sample analysis,the developed method was successfully used to determine the 10 target analytes in 23 batches of Ganoderma samples from different regions.Results indicated that contents of 10 investigated analytes in each sample showed obvious variation.The principal components analysis(PCA)and hierarchical cluster analysis(HCA)analysis classified the samples into three groups,and the HCA tree visualized the relationships which was mainly contributed by geographical partition.The results indicated geographical origin to be an important factor that affect the accumulation of nucleosides and bases in Ganoderma.In summary,this study provides a simple and practical strategy for quality assessment and cultivation reference of Ganoderma.展开更多
A pair of new anticancer nucleosides based on 1,2,4-triazole nucleosides and 1-((2-hydroxyethoxy) methyl)-5-(phenylthio)-1H-1,2,4-triazole-3-carboxamide have been synthesized, and have given the corresponding products...A pair of new anticancer nucleosides based on 1,2,4-triazole nucleosides and 1-((2-hydroxyethoxy) methyl)-5-(phenylthio)-1H-1,2,4-triazole-3-carboxamide have been synthesized, and have given the corresponding products in excellent yields. Its structures and conformations were confirmed by single crystal X-ray diffraction.展开更多
In the presence of tetrazole,2'-substituted nucleosidesreacted ster■os■ifi■ally with n-BuOPIN■_2H_5■_2I_2 to nucleoside 3',5'-■lopnosphites with avial n-Buo group.The stereochemistry of oxidation of...In the presence of tetrazole,2'-substituted nucleosidesreacted ster■os■ifi■ally with n-BuOPIN■_2H_5■_2I_2 to nucleoside 3',5'-■lopnosphites with avial n-Buo group.The stereochemistry of oxidation of■y■lophosphite was investigated.展开更多
The reactions of four different N-（O,O＇-diisopropyl） phosphoamino acids （DIPP-aa）, such as N-phosphoryl-L-α-alanine （DIPP- L-α-Ala）, N-phosphoryl-D-α-alanine （DIPP-D-α-A1a）, N-phosphoryl-β-alanine （DIPP...The reactions of four different N-（O,O＇-diisopropyl） phosphoamino acids （DIPP-aa）, such as N-phosphoryl-L-α-alanine （DIPP- L-α-Ala）, N-phosphoryl-D-α-alanine （DIPP-D-α-A1a）, N-phosphoryl-β-alanine （DIPP-β-A1a） and N-phosphoryl-γ-amino butyric acid （DIPP-γ-Aba）, and four nucleosides, adenosine （A）, guanosine （G）, cytidine （C） and uridine （U）, were studied by electrospray ionization tandem mass spectrometry （ESI-MS/MS） and HPLC/ESI-MS. DIPP-L-α-A1a and DIPP-D-α-A1a produced the same phosphorylated nucleosides, dinucleotides and phosphoroligopeptide. However, DIPP-β-A1a and DIPP-γ-Aba gave no relevant products.展开更多
The hydroxyl group of carbocyclic nucleosides was inversed when the compounds were treated with Me3SiCl, KCN and a catalytic mount of NaI in DMF/CH3CN.
Pyrimidines, such as 6-amino-2-thio and 2-methylthiouracils and fused pyrimidines, such as thienopyrimidines reacted with 1-O-acetyl-2,3,5-tri-O- benzoyl-β-D-ribofuranose to get new derivatives of the corresponding n...Pyrimidines, such as 6-amino-2-thio and 2-methylthiouracils and fused pyrimidines, such as thienopyrimidines reacted with 1-O-acetyl-2,3,5-tri-O- benzoyl-β-D-ribofuranose to get new derivatives of the corresponding nucleosides. The obtained protected nucleosides were deprotected by methanolic sodium methoxide to get the corresponding free uracil and thienopyrimidine nucleosides. The new nucleosides formed were tested for biological activity against some of microorganism (some fungi and bacteria species). Some of the tested products showed moderate activity and the results were reported.展开更多
A new method for the synthesis of perbenzylated, peracetylated and perbenzoylated sugar nucleosides has been carefully studied. In this method trichloroacetoxy and trifluoroacetoxy groups were displaced efficiently in...A new method for the synthesis of perbenzylated, peracetylated and perbenzoylated sugar nucleosides has been carefully studied. In this method trichloroacetoxy and trifluoroacetoxy groups were displaced efficiently in the reaction of nucleoside formation as leaving group. And this method was found to be widely applicable in the study of carbohydrate chemistry.展开更多
In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high effic...In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.展开更多
We quantitatively determined four nucleosides, including cytidine, uridine, guanosine, and adenosine, in Carthamus tinctorius L. and Safflower injection. Separation was performed on a Zorbax Eclipse XDB-18 column usin...We quantitatively determined four nucleosides, including cytidine, uridine, guanosine, and adenosine, in Carthamus tinctorius L. and Safflower injection. Separation was performed on a Zorbax Eclipse XDB-18 column using a gradient elution with mobile phases of 0.05% trifluoroacetic acid （TFA） aqueous solution （A） and methanol （B）. The assay was carried out at a flow rate of 1 mL/min at 25 ℃ with detection at 260 nm. Cytidine, uridine, adenosine and guanosine showed good linearity in the ranges of4.02-503μg/mL （r2= 0.9998）, 9.38-1407 μg/mL （rz = 0.9999）, 80.6-8060μg/mL （r2 = 0.9999） and 2.10---630μg/mL （r2 = 0.9987） with average recoveries of 97.2%, 94.5%, 98.6% and 108.6%, respectively. The contents of cytidine, uridine, adenosine and guanosine in different Carthamus tinctorius L. and Safflower injection were significantly different. This is the first report on the quantitative determination of nucleosides in Carthamus tinctorius L. and Safflower injection.展开更多
Aim To quantitatively determine five nucleosides and nucleobases, including cytidine, uridine, guanosine, adenosine and uracil in different parts of Panax notoginseng. Methods Separation was performed on a Zorbax SB-A...Aim To quantitatively determine five nucleosides and nucleobases, including cytidine, uridine, guanosine, adenosine and uracil in different parts of Panax notoginseng. Methods Separation was performed on a Zorbax SB-Aq column using a gradient elution with mobile phase of 8 mmol^L-1 ammonium acetate aqueous solution （A） and methanol （B）. The assay was carried out at a flow rate of 1 mL·min^-1 at 25 ℃ with the diode-array detection at 260 nm. Results Cytidine, uridine, guanosine, adenosine and uracil had good linearity in the ranges of 1.79 - 57.40 μg·mL^-1 （r^2 = 1.0000）, 3.30 - 105.60 μg·mL^-1 （r^2 = 1.0000）, 3.09 - 98.80 μg·mL^ -1（r^2 = 0.9999）, 2.77 - 88.60 μg·mL^-1 （r^2 = 1.0000） and 0.38 - 12.30 μg·mL ^-1 （r^2 = 1.0000） with average recoveries of 93.9%, 96.5%, 92.7%, 93.2% and 98.8%, respectively. The content of cytidine, uridine, guanosine, adenosine and uracil in different parts of P. notogingeng were significantly different. Conclusion This is the first report on quantitative determination of nucleosides and nucleobases in P notoginseng.展开更多
Pinellia ternata has a long history of medicinal use in China, Japan, and Korea. Herein, we present a sensitive, selective, and robust HPLC method for the simultaneous determination of 6 organic acids （oxalic acid, m...Pinellia ternata has a long history of medicinal use in China, Japan, and Korea. Herein, we present a sensitive, selective, and robust HPLC method for the simultaneous determination of 6 organic acids （oxalic acid, malic acid, citric acid, formic acid, acetic acid, and succinic acid）, 3 nucleosides （uridine, guanosine hydrate, and adenosine）, and ephedrine in P. ternata. The Rhizoma pinelliae samples were collected from different parts of Southwest China, and the 10 constituents were detected at a wavelength of 210 nm. Chromatographic separation was achieved on a Boston Green ODS reversed-phase column along with a gradient mobile phase of methanol and phosphate buffer （pH 2.3, 10 mmol/L, v/v） at a flow rate of 1.0 mL/min. The range of recovery was between 90.8% and 101.9%, and the calibration curves showed high linearity. The relative standard deviations of the new method were less than 3.0% for intra- and inter-day analyses. All samples were stable for at least 48 h. The abundance of the 10 compounds were dependent on their specific locations. The new HPLC method is a powerful technique for the quality control ofP. Ternata.展开更多
Recombinant Escherichia coli pUDP,which overexpressed uridine phosphorylase（UPase）,was constructed.0.5 mmol·L 1lactose had a similar induction effect as the commonly used inducer IPTG during 2.5-5.5 h of cell g...Recombinant Escherichia coli pUDP,which overexpressed uridine phosphorylase（UPase）,was constructed.0.5 mmol·L 1lactose had a similar induction effect as the commonly used inducer IPTG during 2.5-5.5 h of cell growth.The lactose-induced UPase was stable at 50°C.Wet cells of pUDP was used as catalyst to biosynthesize 5-fluorouridine from 30 mmol·L 1uridine and 5-fluorouracil in phosphate buffer（pH 7.0）catalyzed at 50°C for 1.5 h and the yield of 5-fluorouridine was higher than 68%.Under the optimum reaction conditions for production of 5-fluorouridine,5-methyluridine and azauridine were synthesized from uridine by pUDP,the yield was 61.7%and 47.2%respectively.Deoxynucleosides were also synthesized by pUDP,but the yield was only about 20%.展开更多
An environmentally benign and highly efficient one-pot preparation of α-aminophosphonates under solvent-free conditions was developed. By employing this method, 5-aminophosphonate substituted pyrimidine nucleosides w...An environmentally benign and highly efficient one-pot preparation of α-aminophosphonates under solvent-free conditions was developed. By employing this method, 5-aminophosphonate substituted pyrimidine nucleosides were synthesized in good to excellent yields starting from 5-forrnyl-2＇-deoxyuridine, aniline and dimethylphosphite.展开更多
Some novel lipids bearing nucleosides were designed and synthesized as gene vectors, and the structures of these compounds were characterized by UV, IR, 1HNMR, 13CNMR and elemental analysis.
Nucleoside phosphorylase is an important enzyme involved in the biosynthesis of nucleosides. In this study, purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase were co-expressed in Escherichia coli...Nucleoside phosphorylase is an important enzyme involved in the biosynthesis of nucleosides. In this study, purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase were co-expressed in Escherichia coli and the intact cells were used as a catalyst for the biosynthesis of nucleosides. For protein induction, lactose was used in place of isopropyl β-D-l-thiogalactopyranoside （IPTG）. When the concentration of lactose was above 0.5 mmol/L, the ability to induce protein expression was similar to that of IPTG. We determined that the reaction conditions of four bacterial strains co-expressing these genes （TUD, TAD, DUD, and DAD） were similar for the biosyntheses of 2,6-diaminopurine nucleoside and 2,6-diaminopurine deoxynucleoside. When the substrate concentration was 30 mmol/L and 0.5% of the recombinant bacterial cell volume was used as the catalyst （pH 7.5）, a greater than 90% conversion yield was reached after a 2-h incubation at 50℃. In addition, several other nucleosides and nucleoside derivatives were efficiently synthesized using bacterial strains co-expressing these recombinant enzymes.展开更多
A series of 4H-[1,2,5]oxadiazolo[3,4-d]pyrimidine-5,7-dione 1-oxide nucleosides was designed, synthesized and evaluated against vesicular stomatitis virus （VSV） in Wish cell. The antiviral activities of all compound...A series of 4H-[1,2,5]oxadiazolo[3,4-d]pyrimidine-5,7-dione 1-oxide nucleosides was designed, synthesized and evaluated against vesicular stomatitis virus （VSV） in Wish cell. The antiviral activities of all compounds were stronger than those of acyclovir, while their toxicities were similar to those of acyclovir.展开更多
AIM： To investigate the apoptotic effects of nucleosides on the human hepatoma HepG2. METHODS： The nucleosides included inosine （I）, cytidine （C）, uridine （U）, thymidine （T）, adenosine （A）, and guanosine ...AIM： To investigate the apoptotic effects of nucleosides on the human hepatoma HepG2. METHODS： The nucleosides included inosine （I）, cytidine （C）, uridine （U）, thymidine （T）, adenosine （A）, and guanosine （G）. Cells were incubated by the mediums with or without nudeosides at 37 ℃ in a 50 mL/L CO2 humidified atmosphere. RESULTS： It was found that the cell viabilities were significantly decreased, when cells were treated with 30 mmol/L I, 30 mmol/L C, 30 mmol/L U, 30 mmol/L T, 0.5 mmol/L A, and 0.5 mmol/L G after 12 h incubation （P〈0.05）. About the apoptotic phenomenon, the cell percentages of sub-G1 cells were significantly increased in the mediums containing nucleosides such as C, U, T, A, and G （P〈0.05）. Furthermore, the caspase-3 activity was increased, when the cells were incubated with T （P〈0.05）. The protein expressions of p53 and p21 showed no difference in each group. To investigate the mechanism of apoptosis induced by nucleosides, it was found that the contents of soluble Fas ligand contents were increased in HepG2 cells following I, U, T, and A treatment （P〈0.05）. But, TNF-α and cytochrome cwere undetectable. CONCLUSION： Thymidine may induce the apoptosis in HepG2, but the effective dosages and reactive time must be investigated in the future study. However, the apoptosis-inducing abilities of other nucleosides were still unclear in this study.展开更多
基金financially supported by National Natural Science Foundation of China (No.22176167)Fundamental Research Funds for the Central Universities (No.226-2023-00088)Key R&D Program of Zhejiang Province (No.2021C03125)。
文摘RNA modifications have been involved in numerous biological processes, and aberrations of these modifications are tightly associated with various diseases including cancer. Herein, we developed graphenebased solid-phase extraction and robust ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) combined with stable isotope-dilution for simultaneous enrichment and accurate determination of 17 modified nucleosides in human urine. We found graphene could effectively adsorb various modified nucleosides in human urine samples. With this method, we identified and quantified these modified nucleosides in urine samples collected from lung cancer patients and healthy controls.We revealed that the levels of 12 modified nucleosides were all diminished in urine from lung cancer patients, compared with healthy controls. It is worth noting that we demonstrated, for the first time, the presence of 5,2-O-dimethyluridine(m~5U_m) in human urine. Together, we established a robust analytical method for simultaneous determinations of 17 modified nucleosides in human urine, and our results revealed a close correlation between the concentrations of urinary modified nucleosides and the occurrence of lung cancer, implying the potential applications of these modified nucleosides as noninvasive biomarkers for the early detection of lung cancer. Moreover, this study will stimulate future investigations on the regulatory roles of RNA modifications in the initiation and progression of lung cancer.
文摘Aim: To compare the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia, and to study the effect of humidity and heat on the content of nucleosides. Methods: The contents of nucleosides were determined by using high performance capillary electrophoresis (HPCE). Beckman P/ACE System 5010 apparatus equipped with a UV detector and a Beckman untreated fused-silica capillary (57 cm 75 mm, 50 cm effective length) was used. Before sample injection, the capillary was rinsed with 1 molL-1 sodium hydroxide solution and running buffer for 5 min, respectively. A voltage of 20 kV was applied for the separation. Pressure injection was 586 kPa for 6 seconds, and the wavelength of detector was 254 nm. The running time was 20 min at 20 oC. The effect of humidity and heat on the contents of nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia was observed for 1, 3, 5 and 10 days at temperature 40 oC, and relative humidity 75%. Results: The content of nucleosides from natural Cordyceps sinensis was higher than that from cultured Cordyceps mycelia. But the contents of nucleosides from freshly collected natural Cordyceps sinensis were very low, even below the limit of quantitation. The contents of nucleosides from natural Cordyceps sinensis were significantly increased by humidity and heat, but this phenomenon was not observed in cultured Cordyceps mycelia. Conclusion: There are differences between the nucleosides from natural Cordyceps sinensis and cultured Cordyceps mycelia. The nucleosides in natural Cordyceps sinensis may be derived from the degradation of nucleic acids. This implies that adenosine being used for the quality control of natural Cordyceps sinensis may have to be reconsidered.
基金The Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20115103110009)"211"Project Double-Support Plan of Sichuan Agricultural Un iversity(Grant No.03570313)Modernization of Chinese Traditional Medicines in Hainan Province(Grant No.ZY201410)
文摘Determination of nucleosides and nucleobases is important for the quality control of Fritillaria unibracteata Hsiao et K.C. Hsia var. wabuensis （FUW） due to their physiological and pharmacological actions. In the present study, we developed a sensitive and reliable HPLC-diode-array detection method to simultaneously determine ten nucleosides and nucleobases, including cytosine, uracil, cytidine, uridine, thymine, adenine, inosine, guanosine, thymidine and adenosine. Complete separation of all the analytes was achieved on a Zorbax 300 A 300 Extend C18 column with a gradient of methanol-ultrapure water at a flow rate of 1 mL/min in less than 30 min. The diode-array detector wavelength was set at 260 nm for the UV detection of nucleosides and nucleobases. The optimized method provided good linearity （R2〉0.9993 for all the analytes）, satisfactory precision （RSD〈3.715%）, good repeatability （RSD_〈3.748%） and good recovery （RSD from 97.688% to 102.923%）. In addition, the developed method was successfully applied to simultaneous determination of ten nucleosides and nucleobases from FUW, and their content changes of various cultivation time （1-7 years） were further analyzed for the first time. Our findings were useful for ensuring the cultivation time choice of artificial cultivation, quality control, pharmaceutical studies and clinical efficacy of FUW.
基金financially supported by the Research Committee of the University of Macao(MYRG2018-00239-ICMS and MYRG2014-00089-ICMS-QRCM)the Macao Science and Technology Development Fund(162/2017/A3)Guangzhou International Science and Technology Cooperation Project(File no.201807010044)。
文摘Ganoderma(lingzhi)is a famous herbal medicine and edible supplement in oriental countries for a long history.In this study,a simple micellar electrokinetic chromatography(MEKC)method was established for the analysis of nucleosides and bases,the major bioactive components in Ganoderma for the first time.By optimizing the borate concentration,the sodium dodecyl sulfate(SDS)concentration and the pH value of running buffer,10 nucleosides and bases achieved an ideal separation.In real sample analysis,the developed method was successfully used to determine the 10 target analytes in 23 batches of Ganoderma samples from different regions.Results indicated that contents of 10 investigated analytes in each sample showed obvious variation.The principal components analysis(PCA)and hierarchical cluster analysis(HCA)analysis classified the samples into three groups,and the HCA tree visualized the relationships which was mainly contributed by geographical partition.The results indicated geographical origin to be an important factor that affect the accumulation of nucleosides and bases in Ganoderma.In summary,this study provides a simple and practical strategy for quality assessment and cultivation reference of Ganoderma.
文摘A pair of new anticancer nucleosides based on 1,2,4-triazole nucleosides and 1-((2-hydroxyethoxy) methyl)-5-(phenylthio)-1H-1,2,4-triazole-3-carboxamide have been synthesized, and have given the corresponding products in excellent yields. Its structures and conformations were confirmed by single crystal X-ray diffraction.
文摘In the presence of tetrazole,2'-substituted nucleosidesreacted ster■os■ifi■ally with n-BuOPIN■_2H_5■_2I_2 to nucleoside 3',5'-■lopnosphites with avial n-Buo group.The stereochemistry of oxidation of■y■lophosphite was investigated.
基金the National Natural Science Foundation of China(Nos.20572061,20672104)the Chinese Ministry of Education and Zhengzhou University for financial support.
文摘The reactions of four different N-（O,O＇-diisopropyl） phosphoamino acids （DIPP-aa）, such as N-phosphoryl-L-α-alanine （DIPP- L-α-Ala）, N-phosphoryl-D-α-alanine （DIPP-D-α-A1a）, N-phosphoryl-β-alanine （DIPP-β-A1a） and N-phosphoryl-γ-amino butyric acid （DIPP-γ-Aba）, and four nucleosides, adenosine （A）, guanosine （G）, cytidine （C） and uridine （U）, were studied by electrospray ionization tandem mass spectrometry （ESI-MS/MS） and HPLC/ESI-MS. DIPP-L-α-A1a and DIPP-D-α-A1a produced the same phosphorylated nucleosides, dinucleotides and phosphoroligopeptide. However, DIPP-β-A1a and DIPP-γ-Aba gave no relevant products.
文摘The hydroxyl group of carbocyclic nucleosides was inversed when the compounds were treated with Me3SiCl, KCN and a catalytic mount of NaI in DMF/CH3CN.
文摘Pyrimidines, such as 6-amino-2-thio and 2-methylthiouracils and fused pyrimidines, such as thienopyrimidines reacted with 1-O-acetyl-2,3,5-tri-O- benzoyl-β-D-ribofuranose to get new derivatives of the corresponding nucleosides. The obtained protected nucleosides were deprotected by methanolic sodium methoxide to get the corresponding free uracil and thienopyrimidine nucleosides. The new nucleosides formed were tested for biological activity against some of microorganism (some fungi and bacteria species). Some of the tested products showed moderate activity and the results were reported.
文摘A new method for the synthesis of perbenzylated, peracetylated and perbenzoylated sugar nucleosides has been carefully studied. In this method trichloroacetoxy and trifluoroacetoxy groups were displaced efficiently in the reaction of nucleoside formation as leaving group. And this method was found to be widely applicable in the study of carbohydrate chemistry.
基金financially supported by the Young Talents Cultivation Program of the China Association for Science and Technology(No.2015-41)The Training Programme Foundation for the Talents of the Zun Yi Science and Technology Bureau(No.201540)+1 种基金Key Programs of Guizhou Province(125 Program,No.2015039)The Natural Science Foundation of Jiangsu Province(No.BK20141265)
文摘In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.
基金Program for Changjiang Scholar and Innovative Team in University(Grant No.985-2-063-112)
文摘We quantitatively determined four nucleosides, including cytidine, uridine, guanosine, and adenosine, in Carthamus tinctorius L. and Safflower injection. Separation was performed on a Zorbax Eclipse XDB-18 column using a gradient elution with mobile phases of 0.05% trifluoroacetic acid （TFA） aqueous solution （A） and methanol （B）. The assay was carried out at a flow rate of 1 mL/min at 25 ℃ with detection at 260 nm. Cytidine, uridine, adenosine and guanosine showed good linearity in the ranges of4.02-503μg/mL （r2= 0.9998）, 9.38-1407 μg/mL （rz = 0.9999）, 80.6-8060μg/mL （r2 = 0.9999） and 2.10---630μg/mL （r2 = 0.9987） with average recoveries of 97.2%, 94.5%, 98.6% and 108.6%, respectively. The contents of cytidine, uridine, adenosine and guanosine in different Carthamus tinctorius L. and Safflower injection were significantly different. This is the first report on the quantitative determination of nucleosides in Carthamus tinctorius L. and Safflower injection.
文摘Aim To quantitatively determine five nucleosides and nucleobases, including cytidine, uridine, guanosine, adenosine and uracil in different parts of Panax notoginseng. Methods Separation was performed on a Zorbax SB-Aq column using a gradient elution with mobile phase of 8 mmol^L-1 ammonium acetate aqueous solution （A） and methanol （B）. The assay was carried out at a flow rate of 1 mL·min^-1 at 25 ℃ with the diode-array detection at 260 nm. Results Cytidine, uridine, guanosine, adenosine and uracil had good linearity in the ranges of 1.79 - 57.40 μg·mL^-1 （r^2 = 1.0000）, 3.30 - 105.60 μg·mL^-1 （r^2 = 1.0000）, 3.09 - 98.80 μg·mL^ -1（r^2 = 0.9999）, 2.77 - 88.60 μg·mL^-1 （r^2 = 1.0000） and 0.38 - 12.30 μg·mL ^-1 （r^2 = 1.0000） with average recoveries of 93.9%, 96.5%, 92.7%, 93.2% and 98.8%, respectively. The content of cytidine, uridine, guanosine, adenosine and uracil in different parts of P. notogingeng were significantly different. Conclusion This is the first report on quantitative determination of nucleosides and nucleobases in P notoginseng.
基金National Science & Technology Project of China(Grant No.2011BAI13B03)
文摘Pinellia ternata has a long history of medicinal use in China, Japan, and Korea. Herein, we present a sensitive, selective, and robust HPLC method for the simultaneous determination of 6 organic acids （oxalic acid, malic acid, citric acid, formic acid, acetic acid, and succinic acid）, 3 nucleosides （uridine, guanosine hydrate, and adenosine）, and ephedrine in P. ternata. The Rhizoma pinelliae samples were collected from different parts of Southwest China, and the 10 constituents were detected at a wavelength of 210 nm. Chromatographic separation was achieved on a Boston Green ODS reversed-phase column along with a gradient mobile phase of methanol and phosphate buffer （pH 2.3, 10 mmol/L, v/v） at a flow rate of 1.0 mL/min. The range of recovery was between 90.8% and 101.9%, and the calibration curves showed high linearity. The relative standard deviations of the new method were less than 3.0% for intra- and inter-day analyses. All samples were stable for at least 48 h. The abundance of the 10 compounds were dependent on their specific locations. The new HPLC method is a powerful technique for the quality control ofP. Ternata.
基金Supported by"Production,Education&Research"item of Shanghai Baoshan(08-H-4)
文摘Recombinant Escherichia coli pUDP,which overexpressed uridine phosphorylase（UPase）,was constructed.0.5 mmol·L 1lactose had a similar induction effect as the commonly used inducer IPTG during 2.5-5.5 h of cell growth.The lactose-induced UPase was stable at 50°C.Wet cells of pUDP was used as catalyst to biosynthesize 5-fluorouridine from 30 mmol·L 1uridine and 5-fluorouracil in phosphate buffer（pH 7.0）catalyzed at 50°C for 1.5 h and the yield of 5-fluorouridine was higher than 68%.Under the optimum reaction conditions for production of 5-fluorouridine,5-methyluridine and azauridine were synthesized from uridine by pUDP,the yield was 61.7%and 47.2%respectively.Deoxynucleosides were also synthesized by pUDP,but the yield was only about 20%.
基金National Natural Science Foundation of China(Nos.20772025 and 20972042)the Program for Science & Technology Innovation Talents in Universities of Henan Province(No.2008HASTIT006)+1 种基金Innovation Scientists and Technicians Troop Construction Projects of Henan Province(No.104100510019)the Natural Science Foundation of Henan Province(Nos.092300410192 and 094300510054)
文摘An environmentally benign and highly efficient one-pot preparation of α-aminophosphonates under solvent-free conditions was developed. By employing this method, 5-aminophosphonate substituted pyrimidine nucleosides were synthesized in good to excellent yields starting from 5-forrnyl-2＇-deoxyuridine, aniline and dimethylphosphite.
基金This research was supported by the National Natural Science Foundation of China.
文摘Some novel lipids bearing nucleosides were designed and synthesized as gene vectors, and the structures of these compounds were characterized by UV, IR, 1HNMR, 13CNMR and elemental analysis.
文摘Nucleoside phosphorylase is an important enzyme involved in the biosynthesis of nucleosides. In this study, purine nucleoside phosphorylase and pyrimidine nucleoside phosphorylase were co-expressed in Escherichia coli and the intact cells were used as a catalyst for the biosynthesis of nucleosides. For protein induction, lactose was used in place of isopropyl β-D-l-thiogalactopyranoside （IPTG）. When the concentration of lactose was above 0.5 mmol/L, the ability to induce protein expression was similar to that of IPTG. We determined that the reaction conditions of four bacterial strains co-expressing these genes （TUD, TAD, DUD, and DAD） were similar for the biosyntheses of 2,6-diaminopurine nucleoside and 2,6-diaminopurine deoxynucleoside. When the substrate concentration was 30 mmol/L and 0.5% of the recombinant bacterial cell volume was used as the catalyst （pH 7.5）, a greater than 90% conversion yield was reached after a 2-h incubation at 50℃. In addition, several other nucleosides and nucleoside derivatives were efficiently synthesized using bacterial strains co-expressing these recombinant enzymes.
基金the National Natural Science Foundation of China(No.30572240).
文摘A series of 4H-[1,2,5]oxadiazolo[3,4-d]pyrimidine-5,7-dione 1-oxide nucleosides was designed, synthesized and evaluated against vesicular stomatitis virus （VSV） in Wish cell. The antiviral activities of all compounds were stronger than those of acyclovir, while their toxicities were similar to those of acyclovir.
文摘AIM： To investigate the apoptotic effects of nucleosides on the human hepatoma HepG2. METHODS： The nucleosides included inosine （I）, cytidine （C）, uridine （U）, thymidine （T）, adenosine （A）, and guanosine （G）. Cells were incubated by the mediums with or without nudeosides at 37 ℃ in a 50 mL/L CO2 humidified atmosphere. RESULTS： It was found that the cell viabilities were significantly decreased, when cells were treated with 30 mmol/L I, 30 mmol/L C, 30 mmol/L U, 30 mmol/L T, 0.5 mmol/L A, and 0.5 mmol/L G after 12 h incubation （P〈0.05）. About the apoptotic phenomenon, the cell percentages of sub-G1 cells were significantly increased in the mediums containing nucleosides such as C, U, T, A, and G （P〈0.05）. Furthermore, the caspase-3 activity was increased, when the cells were incubated with T （P〈0.05）. The protein expressions of p53 and p21 showed no difference in each group. To investigate the mechanism of apoptosis induced by nucleosides, it was found that the contents of soluble Fas ligand contents were increased in HepG2 cells following I, U, T, and A treatment （P〈0.05）. But, TNF-α and cytochrome cwere undetectable. CONCLUSION： Thymidine may induce the apoptosis in HepG2, but the effective dosages and reactive time must be investigated in the future study. However, the apoptosis-inducing abilities of other nucleosides were still unclear in this study.
