Neopterin

• D-( )- neopterin
• 6 - ( D -erythro -1 ,2,3- trihydroxypropyl ) pterin
• 2 -amino-6 -[( 1S, ​​2R) - 1,2,3- trihydroxypropyl ] - 1 H- pteridin -4-one

• 670-65-5 (mixture of isomers )
• 2009-64-5 (1S, 2R)
• 2277-43-2 (1R, 2S)

Pale yellow crystals

Fixed

Attention

Template: Infobox chemical / molecular formula search available

Neopterin is a signal messenger that special body's immune system cells ( macrophages) is formed.

Chemistry

Neopterin was first isolated in 1889 by Sir Frederick Gowland Hopkins from urine, however, the structure could only be cleared up much later.

From dolls of the honey bee ( Apis mellifera) a new substance from the class of pteridines was purified by chromatography among other pteridine derivatives in tiny isolated yield, for which Heinz Rembold the name suggested neopterin (Greek neo = new). Rembold also recognized the correct structural formula, and proved it by synthesis.

Neopterin contains two carbon atoms with unequal substituents and thus two chiral centers. There are therefore four stereoisomers of the molecule. For the substance of the honey bee, the D- erythro configuration was proved. First, only the D -erythro- form of the absolute configuration of (1S, 2R) was designated as neopterin. Was later found that this enantiomer (1R, 2S )-form (L -erythro- form) in the human and primate urine in addition to the D -erythro- form.

Biochemical importance

Neopterin was long regarded as a precursor of the biosynthesis of biopterin. Later they came to the conclusion that the formation of neopterin might be a side channel of biopterin synthesis, branching from the Dihydroneopterintriphosphat. Biosynthetically produced neopterin as all other natural pteridines from guanosine triphosphate. This is converted with the help of the enzyme GTP cyclohydrolase I in Dihydroneopterintriphosphat from which the alcohol 7,8- dihydroneopterin and its dehydration product, neopterin, can be formed. This was, for example, in treating Dihydroneopterintriphosphat with iodine and alkaline phosphatase.

Neopterin is an indicator of activation of the cellular defense and an indication that the body runs out of an illness. And autoimmune disorders of the neopterin level is increased, as activated T - lymphocytes distribute among other interferon -y which activate macrophages. The pteridine (see pyrimidine ) can be determined in urine, blood and cerebrospinal fluid. In the normal state, the proportion of the blood serum is less than 10 nmol / l

Neopterin is one of the best prognostic marker in patients with HIV infection, with cardiovascular risk and in various malignant tumors.

The neopterin is determined by: