780. Arginine

Nomenclature

CAS number: 74-79-3
l-Arginine; Arg; R; 2-amino-5-guanidinovaleric acid; (S)-2-amino-5-[(aminoiminomethyl)amino]pentanoic acid.
C6H14N4O2; mol wt 174.20.
C 41.37%, H 8.10%, N 32.16%, O 18.37%.

Description and references

An essential amino acid for human development. Precursor for nitric oxide, q.v. Isoln from etiolated lupine seedlings: E. Schulze, E. Steiger, Ber. 19, 1177 (1886). Early chemistry and biochemistry: Amino Acids and Proteins, D. M. Greenberg, Ed. (Charles C. Thomas, Springfield, IL, 1951) 950 pp., passim; J. P. Greenstein, M. Winitz, Chemistry of the Amino Acids vols 1-3 (John Wiley and Sons, Inc., New York, 1961) pp. 1841-1855, passim. Quick isoln from gelatin: R. M. Kothari, J. Chromatogr. 90, 359 (1974). Fluorometric determn in serum: T. Miura et al., Anal. Biochem. 139, 432 (1984). Review of biosynthesis: M. E. Jones, Adv. Enzyme Regul. 9, 19-49 (1970). Review of biochemistry, physiology and therapeutic implication: A. Barbul, J. Parenter. Enteral Nutr. 10, 227-238 (1986). Review of immune function: idem, Nutrition 6, 53-62 (1990). Review of arginine:nitric oxide pathway: S. Moncada, A. Higgs, N. Engl. J. Med. 329, 2002-2012 (1993); R. M. J. Palmer, Curr. Opin. Nephrol. Hypertens. 2, 122-128 (1993). Review of structural role in proteins: C. L. Borders et al., Protein Sci. 3, 541-548 (1994). Review of role in health and renal disease: A. A. Reyes et al., Am. J. Physiol. 267, F331-F346 (1994).

Chemical structure

Properties

Prisms containing 2 mol H2O from water; anhydrous monoclinic plates from 66% alcohol. The dihydrate becomes anhydr at 105°, browns at 230°. Dec 244°. [α]D20 +26.9° (c = 1.65 in 6.0N HCl); [α]D20 +12.5° (c = 3.5 in water); [α]D20 +11.8° (c = 0.87 in 0.5N NaOH). pK1 2.17; pK2 9.04; pK3 12.48. Absorption spectrum: Castille, Ruppol, Bull. Soc. Chim. Biol. 10, 643 (1928); Chem. Zentralbl. II, 622 (1928). The satd aq soln contains 15% (w/w) at 21°. Freely sol in water; sparingly sol in alc. Insol in ether. Strongly alkaline, its aq solns absorb CO2 from the air.

Derivative

Hydrochloride.

Nomenclature

CAS number: 1119-34-2
R-Gene (Pharmacia & Upjohn).
C6H14N4O2.HCl; mol wt 210.66.
C 34.21%, H 7.18%, N 26.60%, O 15.19%, Cl 16.83%.

Properties

Plates, prisms from alc. Sinters at 218°, solidifies again at 225°. Dec 235°. [α]D20 +12.0° (c = 4). [α]D21 +21.9° (c = 12 in dil HCl). Freely sol in water, slightly sol in hot alc.

Therapeutic Category

Ammonia detoxicant (hepatic failure); diagnostic aid (pituitary function).

Keywords

Diagnostic Aid