The hydrogen-to-deuterium isotope exchange reaction of hydrogen in position 5 of pyrimidine derivatives was studied using NMR techniques. The dependence of the reaction rate on the pH and on the solvent composition was explored. In tracer experiments using tritiated water, the application of this exchange reaction was tested for the preparation of pyrimidine derivatives labeled by tritium.
{"title":"Isotope exchange reactions of the hydrogen H-5 of selected pyrimidine derivatives and the preparation of tritium-labeled pyrimidines","authors":"M. Dračínský, P. Jansa, T. Elbert","doi":"10.1135/CCCC2011101","DOIUrl":"https://doi.org/10.1135/CCCC2011101","url":null,"abstract":"The hydrogen-to-deuterium isotope exchange reaction of hydrogen in position 5 of pyrimidine derivatives was studied using NMR techniques. The dependence of the reaction rate on the pH and on the solvent composition was explored. In tracer experiments using tritiated water, the application of this exchange reaction was tested for the preparation of pyrimidine derivatives labeled by tritium.","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"76 1","pages":"1567-1577"},"PeriodicalIF":0.0,"publicationDate":"2011-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011101","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63703943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The nitration of eugenol was investigated by using density functional theory (DFT) calculations. Potential energy surface and molecular electrostatic potential of eugenol was constructed in order to find, respectively, the minimum energy conformers and the possible sites for electrophilic attack. Stationary points were located and characterized at the B3LYP/6-311++G(2d,2p) level of theory. A strongly bound π-complex was found, in which the distance between the nitrogen atom of the NO2 moiety and the C1 carbon atom of the aromatic ring is 2.15 A in the gas phase and 2.06 A in dichloromethane. The most favorable σ-complex or Wheland intermediate is the result from the interaction between the nitrogen and the C6 ring carbon atom. The transition state that connects both complexes is more resembling the σ-complex. The nitronium ion exothermically reacts with eugenol to give the π-complex without an energy barrier. The next stage of the reaction pathway, π-complex → σ-complex, is endothermic and involves a Gibbs energy of activation of 7.9–8.0 kcal mol–1 (gas phase) and 8.3–8.9 kcal mol–1 (CH2Cl2).
{"title":"A theoretical study of the nitration of eugenol with the nitronium ion","authors":"R. Ugarte, G. Salgado, L. Basáez","doi":"10.1135/CCCC2011156","DOIUrl":"https://doi.org/10.1135/CCCC2011156","url":null,"abstract":"The nitration of eugenol was investigated by using density functional theory (DFT) calculations. Potential energy surface and molecular electrostatic potential of eugenol was constructed in order to find, respectively, the minimum energy conformers and the possible sites for electrophilic attack. Stationary points were located and characterized at the B3LYP/6-311++G(2d,2p) level of theory. A strongly bound π-complex was found, in which the distance between the nitrogen atom of the NO2 moiety and the C1 carbon atom of the aromatic ring is 2.15 A in the gas phase and 2.06 A in dichloromethane. The most favorable σ-complex or Wheland intermediate is the result from the interaction between the nitrogen and the C6 ring carbon atom. The transition state that connects both complexes is more resembling the σ-complex. The nitronium ion exothermically reacts with eugenol to give the π-complex without an energy barrier. The next stage of the reaction pathway, π-complex → σ-complex, is endothermic and involves a Gibbs energy of activation of 7.9–8.0 kcal mol–1 (gas phase) and 8.3–8.9 kcal mol–1 (CH2Cl2).","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"79 1","pages":"1529-1548"},"PeriodicalIF":0.0,"publicationDate":"2011-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011156","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63704663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Křováček, H. Dvořáková, I. Votruba, I. Císařová, D. Dvořák
While direct Sonogashira coupling of 6-halopurines with methyl propiolate and with propargyl aldehyde was not successful, the corresponding orthoester and propargyl aldehyde diethylacetal reacted smoothly. Such prepared orthoester was then converted to the desired methylester by methanolysis, the acetal was too stable to be hydrolyzed. The obtained 6-ethynylpurines, bearing orthoester, acetal, methoxycarbonyl and for comparison also the phenyl substituent on the ethynyl group, were subjected to the cycloaddition reaction with cyclopentadiene, diazomethane and phenylazide. Electron deficient alkynylpurines were considerably more reactive in this reaction compared to the not activated phenylethynyl derivative. The prepared alkynylpurines exhibited medium cytostatic activity (IC 50 = 2.6–15 μM), while the cycloadducts were inactive.
{"title":"6-Alkynylpurines bearing electronacceptor substituents: Preparation, reactivity in cycloaddition reactions and cytostatic activity","authors":"M. Křováček, H. Dvořáková, I. Votruba, I. Císařová, D. Dvořák","doi":"10.1135/CCCC2011176","DOIUrl":"https://doi.org/10.1135/CCCC2011176","url":null,"abstract":"While direct Sonogashira coupling of 6-halopurines with methyl propiolate and with propargyl aldehyde was not successful, the corresponding orthoester and propargyl aldehyde diethylacetal reacted smoothly. Such prepared orthoester was then converted to the desired methylester by methanolysis, the acetal was too stable to be hydrolyzed. The obtained 6-ethynylpurines, bearing orthoester, acetal, methoxycarbonyl and for comparison also the phenyl substituent on the ethynyl group, were subjected to the cycloaddition reaction with cyclopentadiene, diazomethane and phenylazide. Electron deficient alkynylpurines were considerably more reactive in this reaction compared to the not activated phenylethynyl derivative. The prepared alkynylpurines exhibited medium cytostatic activity (IC 50 = 2.6–15 μM), while the cycloadducts were inactive.","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"76 1","pages":"1487-1527"},"PeriodicalIF":0.0,"publicationDate":"2011-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011176","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63704319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Daniel González, A. R. Campos, A. Cunha, V. Santos, J. Parajó
Cellulose fibres were employed as reinforcement agent for biodegradable composites using polylactic acid (PLA) as a polymer matrix. PLA can be obtained from renewable resources, and it is attracting much interest owing to its favourable physico-mechanical properties and biodegradability. Prior to composite compounding, two commercial PLA from different suppliers were characterized for apparent density, flow index, crystallinity, thermal properties, melt flow rheology and intrinsic viscosity for comparison. In experiments performed with an integrated compounding–injection moulding machine (ICIM), the effects of the processing conditions on the mechanical properties of composites (tensile strength, stiffness and strain at break) were analyzed using a Taguchi experimental design. Other properties of the composites, such as surface morphology and fibre length distribution, were also considered. ICIM technology provided composites with better mechanical properties and lower fibre degradation than the conventional sequential extrusion and injection moulding (SEIM) technology.
{"title":"Assessment on the effects of the operational conditions on the manufacture of PLA-based composites using an integrated compounding–injection moulding machine","authors":"Daniel González, A. R. Campos, A. Cunha, V. Santos, J. Parajó","doi":"10.1135/CCCC2011166","DOIUrl":"https://doi.org/10.1135/CCCC2011166","url":null,"abstract":"Cellulose fibres were employed as reinforcement agent for biodegradable composites using polylactic acid (PLA) as a polymer matrix. PLA can be obtained from renewable resources, and it is attracting much interest owing to its favourable physico-mechanical properties and biodegradability. Prior to composite compounding, two commercial PLA from different suppliers were characterized for apparent density, flow index, crystallinity, thermal properties, melt flow rheology and intrinsic viscosity for comparison. In experiments performed with an integrated compounding–injection moulding machine (ICIM), the effects of the processing conditions on the mechanical properties of composites (tensile strength, stiffness and strain at break) were analyzed using a Taguchi experimental design. Other properties of the composites, such as surface morphology and fibre length distribution, were also considered. ICIM technology provided composites with better mechanical properties and lower fibre degradation than the conventional sequential extrusion and injection moulding (SEIM) technology.","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"76 1","pages":"1509-1527"},"PeriodicalIF":0.0,"publicationDate":"2011-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011166","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63704708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Milena Sobczak, K. Kubiak, M. Janicka, M. Sierant, B. Mikołajczyk, B. Nawrot
The condensation of the 5′- O -DMT-3′-deoxy-3′-aminothymidine with 3′- O -TBDMS-thymidine- 5′-aldehyde, followed by reduction of the resultant imine derivative and removal of tert -butyldimethylsilyl (TBDMS) protecting group, provided a dimer (denoted as T NH T), which is a congener of dithymidine phosphate with the phosphate linkage 3′-O-P(O)(OH)-O-5′ replaced with an amino group (–NH–). After phosphitylation of the 3′-OH group, the dimer T NH T was introduced (by the standard phosphoramidite approach) into a central part of the nonadecathymidylate. This oligomer exhibited lower affinity to the complementary single and double stranded DNA complements as compared to unmodified T 19 oligonucleotide. The cleavage of modified oligomer with the snake venom and calf spleen phosphodiesterases was completely suppressed at the site of modification. RNA oligomers containing the T NH T dimer were used for preparation of siRNA molecules directed towards mRNA of BACE1 (beta-site amyloid precursor protein cleaving enzyme). The presence of the T NH T units at the 3′-ends of the RNA strands of the siRNA molecule (the siRNA itself is an effective gene expression inhibitor for BACE1) preserved the gene silencing activity and improved the stability of the modified siRNA in 10% fetal bovine serum.
{"title":"SYNTHESIS, PHYSICO-CHEMICAL AND BIOLOGICAL PROPERTIES OF DNA AND RNA OLIGONUCLEOTIDES CONTAINING SHORT ALKYLAMINO INTERNUCLEOTIDE BOND","authors":"Milena Sobczak, K. Kubiak, M. Janicka, M. Sierant, B. Mikołajczyk, B. Nawrot","doi":"10.1135/CCCC2011090","DOIUrl":"https://doi.org/10.1135/CCCC2011090","url":null,"abstract":"The condensation of the 5′- O -DMT-3′-deoxy-3′-aminothymidine with 3′- O -TBDMS-thymidine- 5′-aldehyde, followed by reduction of the resultant imine derivative and removal of tert -butyldimethylsilyl (TBDMS) protecting group, provided a dimer (denoted as T NH T), which is a congener of dithymidine phosphate with the phosphate linkage 3′-O-P(O)(OH)-O-5′ replaced with an amino group (–NH–). After phosphitylation of the 3′-OH group, the dimer T NH T was introduced (by the standard phosphoramidite approach) into a central part of the nonadecathymidylate. This oligomer exhibited lower affinity to the complementary single and double stranded DNA complements as compared to unmodified T 19 oligonucleotide. The cleavage of modified oligomer with the snake venom and calf spleen phosphodiesterases was completely suppressed at the site of modification. RNA oligomers containing the T NH T dimer were used for preparation of siRNA molecules directed towards mRNA of BACE1 (beta-site amyloid precursor protein cleaving enzyme). The presence of the T NH T units at the 3′-ends of the RNA strands of the siRNA molecule (the siRNA itself is an effective gene expression inhibitor for BACE1) preserved the gene silencing activity and improved the stability of the modified siRNA in 10% fetal bovine serum.","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"76 1","pages":"1471-1486"},"PeriodicalIF":0.0,"publicationDate":"2011-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63703994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Using generated conformations from docking analysis by CDOCKER algorithm, some 3D-QSAR models; CoMFA region focusing (CoMFA-RF) and CoMSIA have been created on a series of a new class of potent and non-chiral renin inhibitors. The satisfactory predictions were obtained by CoMFA-RF and CoMSIA based on docking alignment in comparison to CoMFA. Robustness and predictability of the models were further verified by using the test set, cross validation (leave one out and leave ten out), bootstrapping, and progressive scrambling. All-orientation search (AOS) strategy was used to acquire the best orientation and minimize the effect of the initial orientation of aligned compounds. The results of 3D-QSAR models are in agreement with docking results. Moreover, the resulting 3D CoMFA-RF/ CoMSIA contour maps and corresponding models were applied to design new and more active inhibitors.
{"title":"Docking alignment-3D-QSAR of a new class of potent and non-chiral indole-3-carboxamide-based renin inhibitors","authors":"Jahan B. Ghasemi, S. Pirhadi","doi":"10.1135/CCCC2011070","DOIUrl":"https://doi.org/10.1135/CCCC2011070","url":null,"abstract":"Using generated conformations from docking analysis by CDOCKER algorithm, some 3D-QSAR models; CoMFA region focusing (CoMFA-RF) and CoMSIA have been created on a series of a new class of potent and non-chiral renin inhibitors. The satisfactory predictions were obtained by CoMFA-RF and CoMSIA based on docking alignment in comparison to CoMFA. Robustness and predictability of the models were further verified by using the test set, cross validation (leave one out and leave ten out), bootstrapping, and progressive scrambling. All-orientation search (AOS) strategy was used to acquire the best orientation and minimize the effect of the initial orientation of aligned compounds. The results of 3D-QSAR models are in agreement with docking results. Moreover, the resulting 3D CoMFA-RF/ CoMSIA contour maps and corresponding models were applied to design new and more active inhibitors.","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"76 1","pages":"1447-1469"},"PeriodicalIF":0.0,"publicationDate":"2011-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011070","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63704195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Electrochemical impedance spectroscopy (EIS) was used for characterization of electron transfer in various redox probes, such as the redox couple ferrocyanide-ferricyanide, ferrocene, ferrocenemethanol, and the poly(3,4-ethylenedioxythiophene) (PEDOT) conducting polymer containing gold nanoparticles. The PEDOT coating was deposited onto platinum (Pt) and glassy carbon (GC) electrodes by galvanostatic electrochemical polymerization from an aqueous solution containing 10 –2 M EDOT and 10 –1 M LiClO 4 as supporting electrolyte. The PEDOT-Au nanoparticles composite coating was prepared by droplet deposition of Au nanoparticles on top of the Pt/PEDOT and GC/PEDOT modified electrodes. The pure PEDOT and PEDOT-Au nanoparticles composite coatings were investigated using EIS and cyclic voltammetry (CV) in 10 –1 M LiClO 4 solution containing various redox probes. The impedance spectra were recorded at the formal redox potential of the redox probes. The charge transfer resistance ( R ct ), solution resistance ( R s ), exchange current density ( i 0 ), standard rate constant ( k 0 ), and double-layer capacitance ( C dl ) were calculated from the EIS data.
利用电化学阻抗谱(EIS)表征了含金纳米粒子的氧化还原偶对氰化铁-铁氰化物、二茂铁、二茂铁-乙醇和聚(3,4-乙烯二氧噻吩)(PEDOT)导电聚合物中的电子转移。在含有10 -2 M EDOT和10 -1 M liclo4作为支撑电解质的水溶液中，通过恒流电化学聚合将PEDOT涂层沉积在铂(Pt)和玻碳(GC)电极上。通过在Pt/PEDOT和GC/PEDOT修饰电极上滴滴沉积Au纳米粒子，制备了PEDOT-Au纳米粒子复合镀层。在含有多种氧化还原探针的10 -1 M liclo4溶液中，采用EIS和循环伏安法(CV)研究了纯PEDOT和PEDOT- au纳米颗粒复合涂层。在氧化还原探针的形式氧化还原电位处记录阻抗谱。根据EIS数据计算了电荷转移电阻(rct)、溶液电阻(R s)、交换电流密度(i 0)、标准速率常数(k 0)和双层电容(cdl)。
{"title":"Electrochemical impedance spectroscopy study of electron transfer at poly(3,4-ethylenedioxythiophene) containing gold nanoparticles coating","authors":"Stelian Lupu","doi":"10.1135/CCCC2011109","DOIUrl":"https://doi.org/10.1135/CCCC2011109","url":null,"abstract":"Electrochemical impedance spectroscopy (EIS) was used for characterization of electron transfer in various redox probes, such as the redox couple ferrocyanide-ferricyanide, ferrocene, ferrocenemethanol, and the poly(3,4-ethylenedioxythiophene) (PEDOT) conducting polymer containing gold nanoparticles. The PEDOT coating was deposited onto platinum (Pt) and glassy carbon (GC) electrodes by galvanostatic electrochemical polymerization from an aqueous solution containing 10 –2 M EDOT and 10 –1 M LiClO 4 as supporting electrolyte. The PEDOT-Au nanoparticles composite coating was prepared by droplet deposition of Au nanoparticles on top of the Pt/PEDOT and GC/PEDOT modified electrodes. The pure PEDOT and PEDOT-Au nanoparticles composite coatings were investigated using EIS and cyclic voltammetry (CV) in 10 –1 M LiClO 4 solution containing various redox probes. The impedance spectra were recorded at the formal redox potential of the redox probes. The charge transfer resistance ( R ct ), solution resistance ( R s ), exchange current density ( i 0 ), standard rate constant ( k 0 ), and double-layer capacitance ( C dl ) were calculated from the EIS data.","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"13 4 1","pages":"1433-1445"},"PeriodicalIF":0.0,"publicationDate":"2011-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011109","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63704087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Seela, S. Budow, Kuiying Xu, Xiaohua Peng, H. Eickmeier
7-Halogenated 7-deazapurine 2′-C-methylribonucleosides related to adenosine, inosine and guanosine were synthesized employing a “one-pot” glycosylation protocol (Vorbruggen glycosylation). The immunosine 2′-C-methylribonucleoside 4 was prepared by the same glycosylation strategy. By this route, the synthesis of the anti-HCV active compound 7-fluoro-7-deaza-2′-C-methyladenosine (1b) was notably simplified, while other nucleosides were synthesized for the first time. A single-crystal X-ray analysis of 7-fluoro-7-deaza-2′-C-methylinosine (2b) was performed showing that the glycosylic bond adopts an anti orientation (χ = –139.9(2)°), while the sugar moiety has an N conformation (C3′-endo; P = 4.3(1)°, τm = 42.4(1)°).
采用“一锅”糖基化方法(Vorbruggen糖基化)合成了与腺苷、肌苷和鸟苷相关的7-卤化7-去氮杂嘌呤2′- c -甲基核苷。采用相同的糖基化策略制备免疫sin 2′- c -甲基核糖核苷4。通过该途径，抗hcv活性化合物7-fluoro-7-deaza-2 ' - c - methylladenosine (1b)的合成明显简化，其他核苷类也首次合成。对7-氟-7-二氮杂-2′- c -甲基亚氨基甘氨酸(2b)的单晶x射线分析表明，糖基键采用反取向(χ = -139.9(2)°)，而糖部分具有N构象(C3′-端;P = 4.3(1)°，τm = 42.4(1)°)。
{"title":"7-Halogenated 7-deazapurine 2′- C -methylribonucleosides","authors":"F. Seela, S. Budow, Kuiying Xu, Xiaohua Peng, H. Eickmeier","doi":"10.1135/CCCC2011124","DOIUrl":"https://doi.org/10.1135/CCCC2011124","url":null,"abstract":"7-Halogenated 7-deazapurine 2′-C-methylribonucleosides related to adenosine, inosine and guanosine were synthesized employing a “one-pot” glycosylation protocol (Vorbruggen glycosylation). The immunosine 2′-C-methylribonucleoside 4 was prepared by the same glycosylation strategy. By this route, the synthesis of the anti-HCV active compound 7-fluoro-7-deaza-2′-C-methyladenosine (1b) was notably simplified, while other nucleosides were synthesized for the first time. A single-crystal X-ray analysis of 7-fluoro-7-deaza-2′-C-methylinosine (2b) was performed showing that the glycosylic bond adopts an anti orientation (χ = –139.9(2)°), while the sugar moiety has an N conformation (C3′-endo; P = 4.3(1)°, τm = 42.4(1)°).","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"76 1","pages":"1413-1431"},"PeriodicalIF":0.0,"publicationDate":"2011-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011124","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63704361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Nowak, V. Damaraju, C. Cass, J. Young, M. Robins
Nucleosides with an aromatic five-membered ring heterocycle (N, O, or S) fused at C4–C5 of pyrimidin-2-one were prepared by ring closures with 5-(alkyn-1-yl)pyrimidin-2-one intermediates, heterocyclic atom replacements, and ring closure with a 5-aminocytidine derivative. Ultraviolet absorption and emission properties of the autofluorescent products enabled studies on permeation and inhibition of the trans-cellular trafficking effected by human equilibrative nucleoside transporters (hENTs). Some of the autofluorescent nucleosides were shown to be potent and selective inhibitors of human concentrative nucleoside transporters (hCNTs) in a companion study reported elsewhere.
{"title":"Autofluorescent fused-pyrimidine nucleosides: Synthesis and evaluation as permeants and inhibitors of human nucleoside transporters","authors":"I. Nowak, V. Damaraju, C. Cass, J. Young, M. Robins","doi":"10.1135/CCCC2011061","DOIUrl":"https://doi.org/10.1135/CCCC2011061","url":null,"abstract":"Nucleosides with an aromatic five-membered ring heterocycle (N, O, or S) fused at C4–C5 of pyrimidin-2-one were prepared by ring closures with 5-(alkyn-1-yl)pyrimidin-2-one intermediates, heterocyclic atom replacements, and ring closure with a 5-aminocytidine derivative. Ultraviolet absorption and emission properties of the autofluorescent products enabled studies on permeation and inhibition of the trans-cellular trafficking effected by human equilibrative nucleoside transporters (hENTs). Some of the autofluorescent nucleosides were shown to be potent and selective inhibitors of human concentrative nucleoside transporters (hCNTs) in a companion study reported elsewhere.","PeriodicalId":10674,"journal":{"name":"Collection of Czechoslovak Chemical Communications","volume":"76 1","pages":"1395-1412"},"PeriodicalIF":0.0,"publicationDate":"2011-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1135/CCCC2011061","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63703638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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