Decarboxylated arginine. Found in pollen of Ambrosia artemisifolia L., Compositae, in ergot, in sponges, in herring sperm, in octopus muscle: F. W. Heyl, J. Am. Chem. Soc. 41, 670 (1919); A. Kossel, Z. Physiol. Chem. 66, 257 (1910); J. L. Irvin, D. W. Wilson, J. Biol. Chem. 127, 565 (1939). Prepn of salts: DE 463576 (1928 to Schering-Kahlbaum AG). Synthesis: A. Kossel, Z. Physiol. Chem. 68, 170 (1910); K. Odo, J. Chem. Soc. Jpn. 67, 132 (1946); K. Dose, Ber. 90, 1251 (1957). Use as marker for tumor cells: F. S. Steven et al., Anticancer Res. 9, 247 (1989); F. S. Steven et al., J. Enzyme Inhib. 4, 63 (1990).