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ChemInform Abstract: PTERIDINES, LXXV. SYNTHESIS AND PROPERTIES OF BIOPTERIN AND BIOPTERIN ANALOGS
Chemischer Informationsdienst, 1985AbstractAus dem Desoxy‐arabinose‐hydrazon (II) und den Diaminen ( l) werden Biopterin ( 111a), dessen Dimethyl‐Derivat (IIIc) und Biolumazin (IIIb) hergestellt.
M. KAPPEL, R. MENGEL, W. PFLEIDERER
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Journal of the Chemical Society C: Organic, 1969
An unambiguous synthesis of biopterin [2-amino-6-(L-erythro-1,2-dihydroxypropyl)pteridin-4-(3H)-one] is described; based on an improved synthesis of L-neopterin. The synthesis yields biopterin, a naturally occurring pteridine, in a pure, crystalline form without recourse to chromatography. D-Biopterin and D-neopterin are also described.
K. J. M. Andrews +2 more
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An unambiguous synthesis of biopterin [2-amino-6-(L-erythro-1,2-dihydroxypropyl)pteridin-4-(3H)-one] is described; based on an improved synthesis of L-neopterin. The synthesis yields biopterin, a naturally occurring pteridine, in a pure, crystalline form without recourse to chromatography. D-Biopterin and D-neopterin are also described.
K. J. M. Andrews +2 more
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Screening for Biopterin Disorders in PKU
Pediatrics, 1980It is now recognized (Pediatrics 65:806, 1980) that a small proportion of cases of phenylketonuria (PKU) may be due to abnormalities in the metabolism of biopterin. These cases do not respond to the restriction of dietary phenylalanine, but may be benefited by neurotransmitter replacement therapy. A specific diagnosis is therefore desirable.
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Biopterin cofactor and monoamine-synthesizing monooxygenases
Neurochemistry International, 1983The activities of three pterin-requiring monooxygenases, phenylalanine hydroxylase, tyrosine hydroxylase and tryptophan hydroxylase, are regulated by the level of the pterin cofactor, (6R)- l -erythro- tetrahydrobiopterin , which is synthesized from guanosine triphosphate (GTP).
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Quantitation of total biopterin and tetrahydrobiopterin in plasma
Clinical Biochemistry, 2007To develop a reliable method for the determination of tetrahydrobiopterin and total biopterin in plasma.Modifications include blood collection and handling procedures.Collection of blood in the presence of 0.1% (w/v) dithiothreitol and waiting for 2-3 h before centrifugation are optimal for adequate quantitation of both pterins.For a reliable ...
Fekkes, Durk, Kooijman, Ans
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Biopterin metabolism in patients with malignant syndrome
Parkinsonism & Related Disorders, 2003We examined the autopsied brains of two parkinsonian patients who had malignant syndrome (MS). Neopterin and biopterin contents, and GTP cyclohydrolase I activity were measured in various region of the brain. We found relatively higher GTP cyclohydrolase I activities in the hypothalamus compared with other regions of the brain from patients with MS ...
H. Ichinose +7 more
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Pteridine, LXXV. Synthese und Eigenschaften von Biopterin und Biopterin‐Analogen
Liebigs Annalen der Chemie, 1984AbstractDie Synthese von Biopterin (6), seinem 2‐N,N‐Dimethyl‐ (8) und 4‐ Thioxo‐Derivat (19) sowie von Biolumazin (7) wird beschrieben. Durch Umsetzung von Biopterin mit α‐Acetoxyisobuttersäurechlorid läß sich die Seitenkette zu 6‐(L‐threo‐2‐Acetoxy‐1‐chlorpropyl)pterin (10) modifizieren, das als Ausgangsmaterial fär weitere Derivatisierungen dienen ...
Mathias Kappel +2 more
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Biopterin Synthesis Defects: Problems in Diagnosis
Pediatrics, 1984Hyperphenylalaninemia due to a biopterin synthesis defect was detected in an infant with decreased biopterin and increased neopterin levels in plasma and urine. Tetrahydrobiopterin (BH4) administration normalized plasma phenylalanine levels. CSF biopterin and neurotransmitter metabolite levels were normal and with the infant's normal growth and ...
G, Hoganson +7 more
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Urinary levels of neopterin and biopterin in Autism
Neuroscience Letters, 1998The pterins, neopterin and biopterin, occur naturally in body fluids including urine. It is well established that increased neopterin levels are associated with activation of the cellular immune system and that reduced biopterins are essential for neurotransmitter synthesis.
S, Messahel +5 more
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Biosynthesis of biopterin in Ascaris lumbricoides suum
Biochimica et Biophysica Acta (BBA) - General Subjects, 1980In in vivo experiments, radioactivity from [U-14C]GTP was incorporated into biopterin, and, in fact, all carbon atoms of biopterin synthesized in Ascaris lumbricoides suum originated from GTP. Biopterin was also biosynthesized in homogenates of tissue fluid and muscles of Ascaris lumbricoides suum.
H, Otsuka, K, Sugiura, M, Goto
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