Results 201 to 210 of about 8,569 (252)
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1984
Publisher Summary This chapter covers the recent developments, synthetic approaches, and biochemical aspects of pteridines and folates.. The numbering system follows the IUPAC rules; however, the central C=C bond may be substituted. The 2,4(1H, H)-pteridinediones derivatives are called “lumazines.” Reduced compounds are indicated by the prefixes ...
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Publisher Summary This chapter covers the recent developments, synthetic approaches, and biochemical aspects of pteridines and folates.. The numbering system follows the IUPAC rules; however, the central C=C bond may be substituted. The 2,4(1H, H)-pteridinediones derivatives are called “lumazines.” Reduced compounds are indicated by the prefixes ...
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A prototype solid phase synthesis of pteridines and related heterocyclic compounds.
Organic and biomolecular chemistry, 2003The development of a versatile solid phase synthesis of bicyclic polyaza heterocycles including pteridines, purines, and deazapurines is described. The strategy comprises the linking of a pre-formed pyrimidine through a thioether at the 2 or 4 position ...
C. Gibson +2 more
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Syntheses of highly functionalised 6-substituted pteridines.
Organic and biomolecular chemistry, 2003Methods for the synthesis of polyfunctional 6-substituted pteridines from the corresponding 6-aldehydes are described. Alkene, ester, ketone, amide, cyano, oxime, bromo, methoxy and dihydroxy functional groups have all been introduced principally through
D. Guiney, C. Gibson, C. Suckling
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The biosynthesis of pteridines. Part V. The synthesis of riboflavin from pteridine precursors
Journal of the Chemical Society C: Organic, 1968The synthesis and reactions of various 8-substituted lumazine derivatives are described. In particular, it is shown that these compounds readily undergo hydration, and that the resulting carbinol-amines can take part in reactions which involve ring-opening in the pyrazine ring.
Thomas Rowan, H. C. S. Wood
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Pteridines. 51. A new and unequivocal route to C-6 carbon-substituted pterins and pteridines
, 1987Reaction de bromo-6 amino-3 pyrazinecarbonitriles-2 avec des composes acetyleniques (A) en presence de complexes de Pd(II) et Cu(I): obtention des derives alcyne-1yl-6 qui sont cyclises avec la guanidine en diamino-2,4 alcyne-1yl-6 pteridines; hydrolyse ...
E. Taylor, P. Ray
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7-Substituted pterins. A new class of mammalian pteridines.
Journal of Biological Chemistry, 1990Three novel pteridines have been isolated from the urine of patients with a new variant of 6-(L-erythro-1',2'-dihydroxypropyl)-5,6,7,8-tetrahydropterin (tetrahydrobiopterin) deficiency, showing hyperphenylalaninemia.
H. Curtius +6 more
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The Monosubstituted Pteridines
Nature, 1954THE synthesis of a wide variety of monosubstituted pteridines was begun in this Department in 1949, in order to provide less complex pteridines than occur in Nature. We are using the new material to investigate the connexion between constitution and physico-chemical properties (particularly solubility, ionization constants, stability to hydrolysis ...
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Journal of the Chemical Society C: Organic, 1968
Pteridine-2-thiol was reduced by sodium borohydride to the 3,4-dihydro-derivative. Pteridine-2-thiol also reacted readily with sodium hydrogen sulphite and the following potentially carbanionic (‘Michael’) reagents; acetylacetone, ethyl acetoacetate, dimedone, and phloroglucinol.
John J. McCormack, Adrien Albert
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Pteridine-2-thiol was reduced by sodium borohydride to the 3,4-dihydro-derivative. Pteridine-2-thiol also reacted readily with sodium hydrogen sulphite and the following potentially carbanionic (‘Michael’) reagents; acetylacetone, ethyl acetoacetate, dimedone, and phloroglucinol.
John J. McCormack, Adrien Albert
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[55] Chromatographic analysis of pteridines
1980Publisher Summary This chapter discusses the chromatographic analysis of pteridines. Pteridines are present in almost all types of biological tissues. Tetrahydrobiopterin is of interest to many investigators because of its probable role as a cofactor in vivo in mediating several mixed-function oxygenases.
Jon C. Nixon, Takeshi Fukushima
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