6462. Neopterin

Nomenclature

CAS number: 670-65-5
2-Amino-6-(1,2,3-trihydroxypropyl)-4(3H)-pteridinone; 1-(2-amino-4-hydroxy-6-pteridinyl)-1,2,3-propanetriol; 6-(1′,2′,3′-trihydroxy)pterin; Crithidia factor.
C9H11N5O4; mol wt 253.21.
C 42.69%, H 4.38%, N 27.66%, O 25.27%.

Description and references

Precursor in the biosynthesis of biopterin, q.v. Of the four possible isomers, d-erythro, l-erythro, d-threo, l-threo, two have been found in nature: the d-erythro form, to which the term neopterin originally referred; first isolated from the pupae of bees: Rembold, Buschmann, Ann. 662, 72 (1963); the l-threo form, found to be the growth factor for the protozoan Crithidia fasciculata and isolatable from cell-free extracts of Serratia indica: Kobashi, Iwai, Agric. Biol. Chem. 35, 47 (1971); 36, 1685, 1695 (1972). Both natural forms found in human urine: Fukushima, Shiota, J. Biol. Chem. 247, 4549 (1972). Early synthetic studies and structure: Rembold, Buschmann, Ber. 96, 1406 (1963). Synthesis of l-(-)-form: Viscontini, Provenzale, Helv. Chim. Acta 51, 1495 (1968). Synthesis of natural d-neopterin: Viscontini et al., ibid. 53, 1202 (1970).

Chemical structure

Derivative

d-erythro-Form.

Nomenclature

CAS number: 2009-64-5

Properties

[α]D25 +45 ± 3° (c = 0.3 in 0.1N HCl).

Derivative

l-erythro-Form.

Properties

[α]D25 -44 ± 3° (c = 0.3 in 0.1N HCl).

Derivative

d-threo-Form.

Properties

[α]D25 -92 ± 3° (c = 0.3 in 0.1N HCl).

Derivative

l-threo-Form.

Properties

Pale yellow, spiny crystals. [α]D25 +97 ± 3° (c = 0.3 in 0.1N HCl). uv max in 0.1N NaOH: 255, 363 nm (ε 20,900, 7050); in 0.1N HCl: 248, 323 nm (ε 11,200, 7880). Strong blue fluorescence in neutral or alkaline soln; weak fluorescence in acidic soln.