- A new simple nucleoside synthesis
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Persilylation of excess D-ribose or D-glucose with 6-azauracil or N6-benzoyl-adenine followed by condensation with trimethylsilyl triflate in acetonitrile at 80° affords the corresponding persilylated nucleosides. Transsilylation with methanol and chromatography on SiO2 give the pure free nucleosides in up to 70% yield.
- Bennua-Skalmowski,Krolikiewicz,Vorbrueggen
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- 4-alkylated 2-(2,3,5-tri-O-acyl-β-D-ribofuranosyl)- and 2-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)-1,2,4-triazine-3,5-diones
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The alkylation of 2-(2,3,5-tri-O-acyl-β-D-ribofuranosyl)- and 2-(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)- 1,2,4-triazine-3,5-diones with benzyl halides afforded the corresponding 4-benzyl derivatives whose structure was determined by spectral methods, including X-ray analysis. Some of the synthesized compounds were tested for antibacterial and antitumor activity.
- Harutyunyan,Panosyan,Tamazyan,Aivazyan,Danagulyan
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p. 573 - 576
(2017/06/06)
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- THERAPEUTIC FOR HEPATIC CANCER
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A novel pharmaceutical composition for treating or preventing hepatocellular carcinoma and a method of treatment are provided. A pharmaceutical composition for treating or preventing liver cancer is obtained by combining a chemotherapeutic agent with an anti-glypican 3 antibody. Also disclosed is a pharmaceutical composition for treating or preventing liver cancer which comprises as an active ingredient an anti-glypican 3 antibody for use in combination with a chemotherapeutic agent, or which comprises as an active ingredient a chemotherapeutic agent for use in combination with an anti-glypican 3 antibody. Using the chemotherapeutic agent and the anti-glypican 3 antibody in combination yields better therapeutic effects than using the chemotherapeutic agent alone, and mitigates side effects that arise from liver cancer treatment with the chemotherapeutic agent.
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- Anti-Claudin 3 Monoclonal Antibody and Treatment and Diagnosis of Cancer Using the Same
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Monoclonal antibodies that bind specifically to Claudin 3 expressed on cell surface are provided. The antibodies of the present invention are useful for diagnosis of cancers that have enhanced expression of Claudin 3, such as ovarian cancer, prostate cancer, breast cancer, uterine cancer, liver cancer, lung cancer, pancreatic cancer, stomach cancer, bladder cancer, and colon cancer. The present invention provides monoclonal antibodies showing cytotoxic effects against cells of these cancers. Methods for inducing cell injury in Claudin 3-expressing cells and methods for suppressing proliferation of Claudin 3-expressing cells by contacting Claudin 3-expressing cells with a Claudin 3-binding antibody are disclosed. The present application also discloses methods for diagnosis or treatment of cancers.
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- Biochemical detection of cytidine protonation within RNA
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Perturbation of active site functional group pK(a)s is an important strategy employed by protein enzymes to achieve catalysis. There is increasing evidence to indicate that RNAs also utilize functional group pK(a) perturbation for folding and reactivity. One of the best candidates for a functionally relevant pK(a) perturbation is the N3 of C (pK(a) 4.2), which could be sufficiently raised to allow protonation near physiological pH. Here we report the synthesis and use of a series of α-phosphorothioate tagged cytidine analogues whose altered N3 pK(a)s make it possible to efficiently detect functionally relevant protonation events by nucleotide analogue interference mapping. 6-Azacytidine (n6CαS) and 5-fluorocytidine (f5CαS) both have enhanced acidity at the N3 position (pK(a) 2.6 and 2.3, respectively) but leave the hydrogen bonding face of C otherwise unaffected. In contrast, pseudoisocytidine (ΨiCαS) is a charge neutral analogue that mimics the hydrogen bonding character of protonated C. To test the utility of these analogues, we characterized the C300+-G97-C277 mutant form of the Tetrahymena group I intron, which is predicted to require C300 protonation for ribozyme folding and reactivity. At neutral to alkaline pHs, C300 was the only site of n6CαS and f5Cαs interference within the intron, yet both interferences were rescued at acidic pH. Furthermore, ΨiCαS substitution at C300 resulted in enhanced activity at alkaline pHs, consistent with the presence of an N3 proton under the pH conditions studied. Interference mapping with these analogues provides an efficient and sensitive means to identify every site within an RNA where cytidine protonation is important for RNA function and may make it possible to identify C's that participate in general acid/base catalysis within ribozyme active sites.
- Oyelere,Strobel
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p. 10259 - 10267
(2007/10/03)
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- Process for preparing nucleosides with unprotected sugars
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A novel process for nucleoside synthesis, which process comprises reacting the free sugar with heterocyclic bases in the presence of silylating agents in an inert solvent containing a Lewis acid.
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- Process for preparing 2',3',5'-tri-0-acetyl-6-azauridine
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Process for preparing 2',3',5'-tri-0-acetyl-6-azauridine having the following formula SPC1 Which comprises reacting a crude anomeric mixture of methyl D-ribofuranosides having the formula SPC2 With anhydrous hydrogen chloride or anhydrous hydrogen bromide in the presence of acetic anhydride and acetic acid to thereby form the corresponding 2,3,5-tri-0-acetyl-D-ribofuranosyl halide having the formula SPC3 Wherein X is chloro or bromo, reacting the halide of formula III with 3,5-bis-trimethylsilyloxy-1,2,4-triazine having the following formula SPC4 In the presence of an inert solvent and a mercuric halide and recovering the 2',3',5'-tri-0-acetyl-6-azauridine.
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