2009-64-5

off-white to yellow solid

Precursor in the biosynthesis of Biopterin. First isolated from the pupae of bees.

Neopterin is a pyrazino-pyrimidine compound derived from GTP that represents an intermediate product in the synthetic pathway of biopterin and is an essential cofactor in neurotransmitter synthesis. Neopterin is released from macrophages upon immune stimulation with interferon-γ from activated T cells. It is routinely used as a biochemical tool to screen for and monitor the progression of certain diseases accompanied by hyperimmune stimulation.

D-(+)-Neopterin is a pteridine derivative, naturally found in Dictyostelium discoideum. It is found in significant amounts in the urine of cancer patients.

Pterin cofactor; precursor of BH4 (tetrahydrobiopterin).

Store at -20°C

Purification is as for biopterin. Also purify it on a Dowex-1 x 8 (formate form) column and elute with 0.03M ammonium formate buffer pH 8.0 then pH 7.2. The fluorescent neopterin fraction is evaporated under reduced pressure, leaving neopterin and ammonium formate (the latter sublimes out at high vacuum) behind. Stir the residue for 24hours with EtOH, collect the solid and recrystallise it from H2O. [Viscontini et al. Helv Chim Acta 53 1202 1970, cf Wachter et al. Eds Neopterin W de Gruyter, Berlin 1992, ISBN 9783110117905, Beilstein 26 IV 4038.]

[1] RONG-SEN SHEN  Yixian Z  Aftab Alam. Inhibition of GTP cyclohydrolase I by pterins[J]. Biochimica et biophysica acta. General subjects, 1988, 965 1: Pages 9-15. DOI: 10.1016/0304-4165(88)90144-4
[2] C HUBER. Immune response-associated production of neopterin. Release from macrophages primarily under control of interferon-gamma.[J]. Journal of Experimental Medicine, 1984, 160 1: 310-316. DOI: 10.1084/jem.160.1.310