Results 211 to 220 of about 8,420 (250)
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Polarographic Study of Pteridines
Journal of Pharmaceutical Sciences, 1966The electronegativity of the half-wave potentials of a series of pteridine congeners was found to be related to the substituent groups. The 2,4,7-triaminopteridines, 7-substituted 4-amino-2-aryl-6-pteridinecarboxarnides, and 4,7-diamino-2-aryl-6-pteridinecarboxamides were characterized, in that order, by decreasingly lower electronegative half-wave ...
M, Lapidus, M E, Rosenthale
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Nature, 1948
ALTHOUGH many derivatives of pteridine, both natural and synthetic, are known, the parent substance pteridine (I) does not appear to have been described. This substance has now been prepared by the condensation of 4 : 5-diaminopyrimidine with glyoxal bisulphite.
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ALTHOUGH many derivatives of pteridine, both natural and synthetic, are known, the parent substance pteridine (I) does not appear to have been described. This substance has now been prepared by the condensation of 4 : 5-diaminopyrimidine with glyoxal bisulphite.
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Pteridines and affective disorders
Acta Neuropsychiatrica, 2002The pteridine tetrahydrobiopterin (BH4) is an essential cofactor in the biosynthesis of dopamine, (nor)epinephrine, serotonin and nitric oxide (NO). Furthermore, BH4 has a direct influence on release mechanisms of these neurotransmitters and on serotonin receptor binding activityimmunology.
Hoekstra, R (Rosa), Fekkes, Durk
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A New Synthesis of Pteridines.
ChemInform, 2006AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Ming Xu, Andrea Vasella
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Pteridines as Pigments in Amphibians
Science, 1964Extracts of brightly colored skins from nine amphibian species were analyzed chromatographically. In yellow skin in which xanthophores predominated, relatively large quantities of sepiapterin were found, while in red skin which was laden with erythrophores, three drosopterins were most prevalent.
M, OBIKA, J T, BAGNARA
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Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 1975
Summary Over the pH range 1–12, pteridine is reduced at the dropping mercury electrode (DME) and pyrolytic graphite electrode (PGE) by way of three polarographic or voltammetric processes. The first, least negative process, is a reversible 2 e -2H + reduction of pteridine to 5,8-dihydropteridine.
David L. McAllister, Glenn Dryhurst
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Summary Over the pH range 1–12, pteridine is reduced at the dropping mercury electrode (DME) and pyrolytic graphite electrode (PGE) by way of three polarographic or voltammetric processes. The first, least negative process, is a reversible 2 e -2H + reduction of pteridine to 5,8-dihydropteridine.
David L. McAllister, Glenn Dryhurst
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Nature, 1949
THERE is a growing biological interest in derivatives of pteridine (I: R1, R2, R3, R4 = H) as a source of antagonists for folic acid (I: R1 = OH; R2 = NH2 ; R4 = H; R3 = CH2.NH.C6H4.CO.NHCH(COOH): CH2CH2COOH-p), since this vitamin plays an important part in the growth of certain bacteria and normal and malignant tissue.
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THERE is a growing biological interest in derivatives of pteridine (I: R1, R2, R3, R4 = H) as a source of antagonists for folic acid (I: R1 = OH; R2 = NH2 ; R4 = H; R3 = CH2.NH.C6H4.CO.NHCH(COOH): CH2CH2COOH-p), since this vitamin plays an important part in the growth of certain bacteria and normal and malignant tissue.
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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.
T, Rowan, H C, Wood
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Pteridines. IX. Some pteridine isomers of triamterene
Journal of Medicinal Chemistry, 1968J, Weinstock, R Y, Dunoff
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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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