Title: Xanthopterin
CAS Registry Number: 119-44-8
CAS Name: 2-Amino-1,5-dihydro-4,6-pteridinedione
Additional Names: 2-amino-4,6-pteridinediol; 2-amino-4,6-dihydroxypteridine; 2-amino-4,6-dihydroxypyrimido[4,5-b]pyrazine
Molecular Formula: C6H5N5O2
Molecular Weight: 179.14
Percent Composition: C 40.23%, H 2.81%, N 39.09%, O 17.86%
Literature References: Pigment first found in wings of butterflies. Widely distributed in insects and in animals. Has been separated from urine and from the crab. Isoln and structure: Schöpf, Becker, Ann. 507, 266 (1933); 524, 55, 126 (1936); Schöpf, Kottler, Ann. 539, 128 (1939); Wieland, Purrmann, Ann. 544, 163 (1940). See also Fukushima, Shiota, J. Biol. Chem. 247, 4549 (1972). Synthesis: Purrmann, Ann. 546, 98 (1940); 548, 284 (1941); Koschara, Z. Physiol. Chem. 277, 159 (1943); Totter, J. Biol. Chem. 154, 105 (1944); Elion et al., J. Am. Chem. Soc. 71, 741 (1949); Koschara, DE 859471 (1952 to Bayer), C.A. 52, 10222f (1958); Stuart, Wood, J. Chem. Soc. 1963, 4186. Facile synthesis: Taylor, Jacobi, J. Am. Chem. Soc. 95, 4455 (1973); Taylor et al., J. Org. Chem. 40, 2341 (1975). Exhibits tumor inhibitory properties.
Derivative Type: Monohydrate
Properties: Orange-yellow crystals, sinters around 360°, decomp above 410°. Practically insol in water. Freely sol in dil NH4OH and NaOH giving yellow solns and in 2N HCl giving colorless solns. uv max at pH 11: 255, 390 nm (E1%1cm 0.92, 0.355). Can be converted by yeast into folic acid.
Absorption maximum: uv max at pH 11: 255, 390 nm (E1%1cm 0.92, 0.355)
Xanthosine Xanthoxyletin Xanthoxylin Xanthurenic Acid Xanthyletin

CAS number 119-44-8 N
PubChem 8397
ChemSpider 8091 YesY
UNII V66551EU1R YesY
Jmol-3D images Image 1
Molecular formula C6H5N5O2
 N (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Xanthopterin is a yellow, crystalline solid[1] that occurs mainly in the wings of butterflies and in the urine of mammals.[1] Small microorganisms convert it into folic acid.[2] It is the end product of a non-conjugated pteridine compound[3] and inhibits the growth of lymphocytes produced by concanavalin.[3] High levels of the chemical were found in patients with liver disease and hemolysis, the latter increasing levels by 35%.[4][5]

It has been suggested that the Oriental hornet uses xanthopterin as a light-harvesting molecule to transform light into electrical energy, which may explain why the insects are more active when light intensity is greater. Although no explicit biochemical mechanism has been determined for this animal light-to-energy conversion system, it remains an active and important area of scientific research (Plotkin et al., Naturwissenschaften (2010) 97:1067–1076).[6]