Tubercidin
Mostrando 1-12 de 24 artigos, teses e dissertações.
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1. Action of tubercidin a toxic purine analogue in Leishmania spp / Ação do análogo de purina tóxico tubercidina em Leishmania ssp.
Gene identification associated with drug resistance has contributed to a better understanding of the mechanism of action of anti parasitic compounds. Using transfection and over-expression selection strategy we isolated two loci related with the resistance of tubercidin (TUB), a toxic analog purine. In the first locus we identified an ortholog of the TOR gen
Publicado em: 2008
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2. Prevention of tubercidin host toxicity by nitrobenzylthioinosine 5'-monophosphate for the treatment of schistosomiasis.
Host toxicity of the dose regimen of tubercidin (7-deazaadenosine) plus nitrobenzylthioinosine 5'-monophosphate (NBMPR-P) used in combination therapy of schistosomiasis (M. H. el Kouni, D. Diop, and S. Cha, Proc. Natl. Acad. Sci. USA 80:6667-6670, 1983; M. H. el Kouni, N. J. Messier, and S. Cha, Biochem. Pharmacol. 36:3815-3821, 1987) was examined in vivo in
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3. Total synthesis of certain 2-, 6-mono- and 2,6-disubstituted-tubercidin derivatives. Synthesis of tubercidin via the sodium salt glycosylation procedure.
Direct glycosylation of the sodium salt of 4,6-dichloro- or 4,6-dibromo-2-methylthiopyrrolo[2,3-d]pyrimidine with 2,3,5-tri-O-benzoyl-D-ribofuranosyl bromide gave good yield of the corresponding N7-glycosylated pyrrolo [2,3-d]pyrimidine. The intermediate 4-amino-6-chloro-2-methylthio-7-beta-D-ribofuranosylpyrrolo[2,3-d] pyrimidine provided a new synthetic ro
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4. Halogenation of tubercidin by N-halosuccinimides. A direct route to 5-bromotubercidin, a reversible inhibitor of RNA synthesis in eukaryotic cells.
Tubercidin may be directly brominated by reaction with N-bromosuccinimide in DMF to give 5-bromotubercidin, a reversible inhibitor of RNA synthesis. When buffered with potassium acetate the major product is 6-bromotubercidin. 5,6-Dibromotubercidin is formed in minor amounts under both conditions. N-Chlorosuccinimide and tubercidin give 5-chlorotubercidin and
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5. Antirhinovirus activity of purine nucleoside analogs.
A wide variety of purine nucleoside (mainly tubercidin and adenosine) analogs, which had previously been shown to inhibit the replication of a broad spectrum of RNA viruses, were evaluated for their antirhinovirus activity in human diploid (WI-38) fibroblasts. Tubercidin, 5-(1-hydroxyethyl)tubercidin, 5-(2-buten-1-yl)tubercidin, toyocamycin, and sangivamycin
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6. Combination therapy of schistosomiasis by tubercidin and nitrobenzylthioinosine 5'-monophosphate.
Nitrobenzylthioinosine 5'-monophosphate (NBMPR-P) inhibits the transport of nucleosides, including tubercidin, in mammalian systems but not in Schistosoma mansoni. Administration of NBMPR-P with high doses of tubercidin (lethal doses if injected alone) by intraperitoneal injection into S. mansoni-infected mice was highly toxic to the parasite but not to the
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7. Genetic analysis of nucleoside transport in Leishmania donovani.
Genetic dissection of nucleoside transport in Leishmania donovani indicates that the insect vector form of these parasites possesses two biochemically distinct nucleoside transport systems. The first transports inosine, guanosine, and formycin B, and the second transports pyrimidine nucleosides and the adenosine analogs, formycin A and tubercidin. Adenosine
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8. Poly(adenylic acids) containing the antibiotic tubercidin -- base pairing and hydrolysis by nuclease S1.
Poly(adenylic acids) containing the antibiotic tubercidin (7-deazaadenosine) form double strands with poly(uridylic acid) by Watson-Crick base pairing. The stability of these complexes is enhanced by an increasing adenosine content of the polymers. Whereas poly(tubercidylic acid) can bind only one poly(U) chain, the copolymers of adenylic and tubercidylic ac
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9. BIOLOGICAL AND BIOCHEMICAL PROPERTIES OF THE ANALOGUE ANTIBIOTIC TUBERCIDIN
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10. Adenosine kinase-deficient mutant of Neurospora crassa.
Tubercidin-resistant mutant strains of Neurospora crassa were isolated, and at least one appeared to be deficient in adenosine kinase. No significant differences in [8-14C]adenosine labeling of purine nucleotides or nucleosides were found between the wild type and the adenosine kinase-deficient strains.
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11. Xylotubercidin against herpes simplex virus type 2 in mice.
Of a series of newly synthesized derivatives of the pyrrolo[2,3-d]pyrimidine nucleosides tubercidin, toyocamycin, and sangivamycin, the xylosyl analog of tubercidin, xylotubercidin, exhibited the greatest potency and selectivity against herpes simplex virus type 2 (HSV-2) in vitro. At dosage regimens that were not toxic for the host, xylotubercidin proved ef
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12. Formycin B-resistant mutants of Chinese hamster ovary cells: novel genetic and biochemical phenotype affecting adenosine kinase.
Stable mutants which are approximately three- and eightfold resistant to the pyrazolopyrimidine nucleosides formycin A and formycin B (FomR) have been selected in a single step from mutagenized Chinese hamster ovary cells. In cell extracts, the two FomR mutants which were examined were both found to contain no measurable activity of the enzyme adenosine kina