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1.
Dagmara Baraniak Piotr Ruszkowski Daniel Baranowski Grzegorz Framski Jerzy Boryski 《Nucleosides, nucleotides & nucleic acids》2013,32(12):980-1005
AbstractTwo series of novel fluorinated nucleosides dimers with an unnatural 1,2,3-triazole linkage were synthesized. The obtained molecules were prepared using “click” chemistry approach based on copper(I) catalyzed Huisgen azide–alkyne cycloaddition. It was performed between 3′- and 5′-azido-nucleosides as the azide components, and the 3′-O- and 5′-O-propargyl-nucleosides as the alkyne components. Based on analysis of the 3JHH, 3JH1′C2 and 3JH1′C6 we estimated conformational preferences of sugar part and orientation around glycosidic bond. All described nucleosides dimers analogs were characterized by spectroscopic methods and evaluated for their in vitro cytotoxicity in three human cancer cell lines: cervical (HeLa), oral (KB) and breast (MCF-7). 相似文献
2.
《Nucleosides, nucleotides & nucleic acids》2013,32(4-7):1211-1217
The intra- and intermolecular hydrogen bonding (ΔGº298K ≈ 2, kcal mol?1) of 2′-OH in nucleos(t)ides has been reported by the temperature- and concentration-dependent NMR study in conjunction with dihedral dependence of the NMR derived both endo (3 J H,H)- and exocyclic (3 JH,OH) coupling constants, nOe contacts and lineshape analyses of hydroxyl protons for EtpA (1), 3′-dA (2), rA (3), 2′-dA (4) [Fig. 1] in DMSO-d 6 at 500 MHz.
MOLECULAR MODELLING OF 2′-OH MEDIATED HYDROGEN BONDING IN RIBONUCLEOS(T)IDES BY NMR CONSTRAINED AM1 AND MMX CALCULATIONS
Published online:
07 February 2007 Figure 1. The schematic representation of the bias of the dymanic two-state pseudorotational equilibrium between the North-type (N, C2′-exo -C3′-endo) and the South-type (S, C3′-exo-C2′-endo) [3a] pseudorotamers of the sugar moeity for EtpA (1), 3′-dA (2), rA (3), 2′-dA (4) and torsion (Φ) around C2′/3′-O bond viz. Φ1 = ΦH2′?C2′?O?H and Φ2 = ΦH3′?C3′?O?H except in 1 where the torsion across C3′-O3′ bond is actually ?? [C4′-C3′-O3′-P]. 相似文献
3.
Srinivas Gopu Vuradi Ravi kumar Kotha Laxma Reddy Putta Venkat Reddy 《Nucleosides, nucleotides & nucleic acids》2019,38(5):349-373
A novel ligand BOPIP (BOPIP?=?{2-(4-(benzyloxy)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline}) and its mononuclear Ru(II) polypyridyl complexes [Ru(phen)2 BOPIP]2+(1) (phen?=?1,10-Phenanthrolene), [Ru(bpy)2 BOPIP]2+(2) (bpy?=?2,2′ bipyridyl), [Ru(dmb)2 BOPIP]2+(3) (dmb?=?4, 4′ -dimethyl 2, 2′ -bipyridine), [Ru(Hdpa)2 BOPIP]2+(4) (Hdpa?=?2,2′dipyridylamine) have been synthesized successfully and characterized by elemental analysis, UV-vis, IR, 1H, 13C-NMR, and ESI-MS Spectroscopy. The interaction of these complexes with CT-DNA was studied using absorption, emission techniques, viscosity measurements and molecular docking studies. The docking study also supports the binding ability of complexes obtained through the absorption and emission techniques. These studies reveal that the Four Ru(II) polypyridyl complexes bind to DNA predominantly by intercalation. The Antimicrobial activity and cytotoxicity of these complexes are also reported. 相似文献
4.
Jens Haas Thea Mueller-Kuller Stefan Klein Joachim W. Engels 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):865-868
We recently reported that a 1′-deoxy-1′-(4,6-difluoro-1H-benzimidazol-1-yl)-2′-(β-aminoethyl)-β-d-ribofuranose nucleoside appears to be a universal nucleoside which does not differentiate between the four natural nucleosides A, C, G, and U in duplexes. Moreover, ribozymes modified with this nucleoside analog showed a better or at least equal catalytic activity relative to Watson-Crick mismatches.[ 1 ] Due to these data, we investigated the ability of this compound to tolerate Watson-Crick mismatches in order to avoid HIV escape mutations in RNA interference. The influence of this nucleoside analog on siRNA efficiency was analyzed with a proven siRNA targeting GFP. 相似文献
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6.
Novel 1-phenyl-4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenoxy)methyl)-1H-1,2,3-triazole derivatives were synthesized by click chemistry reaction and screened for antimicrobial activity against grampositive and gram-negative bacterial and fungal species. All the compounds were characterized by 1H and 13C NMR, IR, and mass spectral data. The results of antibacterial study indicated that 1-(4-nitrophenyl)-4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenoxy)methyl)-1H-1,2,3-triazole, 1-(4-(4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenoxy)methyl)-1H-1,2,3-triazol-1-yl)phenyl)ethanone, 1-(2,6-dichloro-4-nitrophenyl)-4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenoxy)methyl)-1H-1,2,3-triazole, and 1-(2-methoxy-4-nitrophenyl)-4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenoxy)methyl)-1H-1,2,3-triazole showed appreciable antibacterial activity while 1-(4-fluorophenyl)-4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenoxy) methyl)-1H-1,2,3-triazole, 1-(2,6-dichloro-4-nitrophenyl)-4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenoxy)methyl)-1H-1,2,3-triazole, and 1-(4-methoxyphenyl)-4-((4-(1,4,5-triphenyl-1H-imidazol-2-yl)phenoxy)methyl)-1H-1,2,3-triazole emerged as the most potential antifungal agents. 相似文献
7.
《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):103-116
The seco C-nucleosides 3-(1,2,3,4,5-penta-O-acetyl-D-gluco- and D- galacto-pentitol-1-yl)-1H-1,2,4-triazoles (8 and 9) were obtained in a one pot by deamination and dethiolation of 4-amino-3-(D-gluco- and D-galacto-pentitol-1-yl)-5-mercapto-1,2,4-triazoles (1 and 2), respectively, using sodium nitrite in orthophosphoric acid and subsequent acetylation. Condensation of 1, 2, and 4-amino-3-(D-glycero-D-gulo-hexitol-1-yl)-5-mercapto-1,2,4-triazole (12) with phenacylbromide (11) afforded the corresponding 3-(D-gluco-, D-galacto-pentitol-1-yl) and 3-(D-glycero-D-gulo-hexitol-1-yl)-6-phenyl-7H-1,2,4- triazolo[3,4-b][1,3,4] thiadiazines (15, 16, and 17). Acetylation of 15–17 gave the penta- and hexa-O-acetyl derivatives 18–20, respectively. The structures were confirmed by using 1H, 13C, and 2D NMR spectra, DQFCOSY, HMQC, and HMBC experiments. The favored conformational structures were deduced from the vicinal coupling constants of the protons. 相似文献
8.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):967-972
Abstract The chemical synthesis and biological evaluation of some acyclic α-[6-(1′-carbamoylalkylthio)-1H-pyrazolo[3,4-d]pyrimidin-4-yl]thioalkylamide nucleosides are described. 相似文献
9.
Abstract (1′R, 3′S and R, 5′S)-4′-Oxo-2′-oxabicyclo[3.1.0]hexan-3′-yl pyrimidines and purines were synthesized from ribonucleosides in 2-5 steps. The configurations of the base moieties in the cyclopropano keto-nucleosides were determined by NOE difference spectroscopy. 相似文献
10.
Sixteen disubstituted 1,2,3-triazoles were prepared using the Huisgen cycloaddition reaction and evaluated as inhibitors against caspase-3. The two most potent inhibitors were found to be (S)-1-((1-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-1H-1,2,3-triazol-4-yl)methyl)-5-((2-(methoxymethyl)pyrrolidin-1-yl)sulfonyl)indoline-2,3-dione (7f) and (S)-1-((1-benzyl-1H-1,2,3-triazol-5-yl)methyl)-5-((2-(methoxymethyl)pyrrolidin-1-yl)sulfonyl)indoline-2,3-dione (8g) with IC50-values of 17 and 9 nM, respectively. Lineweaver-Burk plots revealed that these two triazoles show competitive inhibitory mechanism against caspase-3. 相似文献
11.
《Nucleosides, nucleotides & nucleic acids》2013,32(3):229-241
The Divakar-Reese procedure has been successfully applied for transforming 7-oxo-isothiazolo[4,5-d]pyrimidine C-nucleosides (4a,b, 5a,b, 6a) via 1,2,4-triazol-1-yl intermediates (7a,b, 8a,b) into various 7-substituted C-nucle- osides 15a,b, 16a,b, 17a, 18a, 19a,b, 20a,b; their subsequent deprotection provides novel types of unusual C-glycosides 22b, 23a, 24a,b, 25b, 26b. C-Nucleosides, possessing on its heterocyclic base other than naturally occuring oxo- or amino substituents, are important model compounds for biological or medicinal studies [2a], [2b], [2c], [2d], [2e], [2f], [2g], [2h], [2i] [3a], [3b], [3c], [3d], [3e], [3f], [3g], [3h]. We want to report on the synthesis of novel 7-substituted isothiazolo = [4,5-d]pyrimidine C-nucleosides. As we could show in previous papers [1], [4], there exists a simple approach to the protected C-glycosides 4–6. 相似文献
12.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):1117-1118
Abstract The efficient synthesis of oligonucleotides containing 2′-O-β-D-ribofuranosyl (and β-D-ribopyranosyl)nucleosides, 2′-O-α-D-arabinofuranosyl (and α-L-arabinofuranosyl)nucleosides, 2′-O-β-D-erythrofuranosylnucleosides, and 2′-O-(5′-amino-5-deoxy-β-D-ribofuranosyl)nucleosides have been developed. 相似文献
13.
We investigated the morphology, morphogenesis and small subunit rRNA gene-based phylogeny of three marine urostylids, Uncinata gigantea Bullington, 1940, Holosticha heterofoissneri Hu & Song, 2001, and Holosticha cf. heterofoissneri. The dorsal morphogenesis of Uncinata gigantea shows de novo formation of two groups of anlagen near the marginal rows. Holosticha cf. heterofoissneri demonstrates fragmentation of the first dorsal kinety anlage as in Holosticha heterofoissneri. Our population of H. heterofoissneri corresponds well with previously described populations in terms of its general morphology and ciliary pattern. Uncinata gigantea can be recognized by its large and highly contractile body, yellowish to brownish cell colour, two types of cortical granules, and 20–30 transversely oriented and densely arranged cirri in the left marginal row, which often overlie the buccal vertex. Based on the new data, especially infraciliature, the genus Uncinata is here redefined. Both the morphology and phylogenetic analyses suggest that the genus Uncinata should be classified within the family Urostylidae. In addition, both morphological and morphogenetic data suggest that Holosticha bradburyae Gong et al., 2001 should be transferred to Uncinata as U. bradburyae (Gong et al., 2001) comb. nov., due to its possession of a characteristically prominent beak-like, leftwards curved projection and the developmental mode of the dorsal kineties. This assignment is supported by the phylogenetic analyses, which placed Uncinata gigantea in a clade with U. bradburyae (Gong et al., 2001) comb. nov., and revealed only 1.13% (19 bp) difference in their SSU-rDNA gene sequence. 相似文献
14.
Kikue Kubota Akio Kobayashi Tei Yamanishi 《Bioscience, biotechnology, and biochemistry》2013,77(11):2753-2754
Quinoxaline and benzimidazole derivatives obtained from L-rhamnose and L-fucose under deoxygenated, weakly acidic, heated conditions were studied using GLC, HPLC, and NMR.Four quinoxalines and one benzimidazole were obtained from L-rhamnose (RHA-I, II, III, III′, and IV) and L-fucose (FUA-I, II, III, IV, and V) in an acidic solution (MeOH-AcOH-H2I = 8 : 1 : 2) at 80°C. The total yield of the products as sugar was about 80% from either rhamnose or fucose.The structure of RHA-I was (2′S)-2-methyl-3-(2′-hydroxypropyl)quinoxaline; RHA-II, (2′R,3′S)-2-(2′,3′-dihydroxybutyl)quinoxaline; RHA-III, (1′S,2′S,3′S)-2-(1′2′3′-trihydroxybutyl)quinoxaline[2-(L-arabino-1′,2′,3′-trihydroxybutyl)quinoxaline]; RHA-III′, 2-(L-ribo-1′,2′,3′-trihydroxybutyl)quinoxaline; and RHA-IV, 2-(L-manno-1′,2′,3′,4′-tetrahydroxypentyl)-benzimidazole, and the structure of FUA-I was the same as RHA-I; FUA-II, (2′S, 3′S)-2-(2′, 3′-dihydroxybutyl)quinoxaline; FUA-III, (1′R, 2′R, 3′S)-2-(1′,2′,3′-trihydroxybutyl)quinoxaline [2-(L-xylo-1′,2′,3′-trihydroxybutyl)quinoxaline; FUA-IV, 2-(L-lyxo-1′,2′,3′-trihydroxybutyl)-quinoxaline; and FUA-V, 2-(L-galacto-1′,2′,3′,4′-tetrahydroxypentyl)benzimidazole. These results suggest no significant difference for the pathways of quinoxaline and benzimidazole formation between L-rhamnose and L-fucose. Possible pathways are proposed for each sugar. 相似文献
15.
E. Amadio A. Scrivanti G. Chessa U. Matteoli A. Dolmella 《Inorganica chimica acta》2011,370(1):388-12124
The synthesis and characterization of the cationic complex [Pd(η3-C3H5)(2-((4-phenyl-1H-1,2,3-triazol-1-yl)methyl)pyridine)](BF4) (2) are reported. The solid-state structure of 2 has been unambiguously confirmed by single-crystal X-ray diffraction analysis. 1H NMR spectroscopy reveals that in solution complex 2 is dynamic and that syn-syn, anti-anti exchange of the allyl protons occurs. Complex 2 exhibits good activity in the Suzuki-Miyaura coupling of aryl bromides with phenyl boronic acid. 相似文献
16.
AbstractThe checklist comprises all species of six families of Iranian aquatic Polyphaga (Coleoptera). In total, 43 species/subspecies within the families, Georissidae (one species), Helophoridae (25 species and two subspecies), Hydrochidae (three species), Spercheidae (one species), Curculionidae (nine species) and Erirhinidae (two species) are listed for the fauna of Iran. Helophorus (Rhopalohelophorus) nanus Sturm, 1836 (Helophoridae) is recorded for the first time from Iran. We also present two additional species lists: one with incorrect records (one species) and the other with unidentified species. 相似文献
17.
Martin Lillig 《Zoology in the Middle East.》2013,59(4):345-352
The first Asian member of Orostegastopsis Koch, 1962 is described and figured: O. planioculata sp. n., which can be easily distinguished from the two Somalian species O. scorteccii Koch, 1962 and O. kaszabi (Bremer, 1985) comb. nov. by the shallow eyes. According to the shape of the clypeus, Stegastopsis kaszabi Bremer, 1985 is transferred from the genus Stegastopsis Kraatz to the genus Orostegastopsis Koch as was already indicated by Bremer (1985) who treated Orostegastopsis as a subgenus of Stegastopsis: Orostegastopsis kaszabi (Bremer, 1985) comb. nov. Keys to the species of Stegastopsis and Orostegastopsis are given. 相似文献
18.
Abstract Hydrochus ignicollis Motschulsky, 1860 is recorded from Iran (Gilan Province) for the first time. In addition, new Iranian provincial records are provided for two species: H. nodulifer Reitter, 1897 (Zanjan Province) and H. farsicus Hidalgo-Galiana, Jäch, and Ribera, 2010 (Kohgiluyeh and Boyer-Ahmad Province). Photographs of the habitus, the male genitalia and the habitat of H. ignicollis are provided. 相似文献
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20.
Malina Jasamai Jan Balzarini Claire Simons 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):56-61
The synthesis of dideoxy-6-azathymidine 4′-thionucleoside 1-(2,3-dideoxy-4-thio-β-D-erythro-pentofuranosyl)-(6-azathymidine) (2), and the L-nucleoside, 1-(4-thio-β-L-erythro-pentofuranosyl)-(6-azathymidine) (3) and their evaluation against a wide panel of antiviral assays are described. The L-thionucleoside (3) was devoid of antiviral activity. The dideoxy-thionucleoside (2) was moderately active against vaccinia virus (VV) and the herpes simplex virus strains HSV-1 (strain KOS) and HSV-2 (strain G) (MIC 12 μM) and retained inhibitory activity vs a thymidine kinase-deficient strain HSV-1/TK–, suggesting that (2) is not dependent on viral TK-catalysed phosphorylation for antiviral activity and/or may use an alternative metabolic activation pathway. 相似文献