| Title:  Droxidopa CAS Registry Number:  23651-95-8 CAS Name:  threo-b,3-Dihydroxy-L-tyrosine Additional Names:  L-threo-3-(3,4-dihydroxyphenyl)serine;  (-)-(2S,3R)-2-amino-3-hydroxy-3-(3,4-dihydroxyphenyl)propionic acid;  threo-dopaserine;  L-threo-DOPS;  L-DOPS Manufacturers' Codes:  SM-5688 Trademarks:  Dops (Sumitomo) Molecular Formula:  C9H11NO5 Molecular Weight:  213.19 Percent Composition:  C 50.70%, H 5.20%, N 6.57%, O 37.52% Literature References:  Synthetic amino acid precursor of norepinephrine, q.v.  Prepn of racemate:  K. W. Rosenmund, H. Dornsaft, Ber. 52B, 1734 (1919).  Separation and resolution of diastereomers:  B. Hegedüs et al., Helv. Chim. Acta 58, 147 (1975); B. Hegedüs, A. Krasso, US 3920728 (1975 to Hoffmann-La Roche).  Improved process for production:  N. Ohashi et al., US 4319040 (1982 to Sumitomo).  Pharmacology of stereoisomers:  G. Bartholini et al., J. Pharmacol. Exp. Ther. 193, 523 (1975).  Clinical pharmacology of L-threo-form and clinical evaluation in familial amyloid polyneuropathy (FAP):  T. Suzuki et al., Eur. J. Clin. Pharmacol. 17, 429 (1980).  Reversed-phase chromatography determn in plasma and urine:  F. Boomsma et al., J. Chromatogr. 427, 219 (1988).  Pharmacokinetics in FAP:  T. Suzuki et al., Eur. J. Clin. Pharmacol. 23, 463 (1982); in parkinsonism:  T. Suzuki et al., Neurology 34, 1446 (1984).  Metabolism to norepinephrine:  T. Suzuki et al., Life Sci. 36, 435 (1985).  Clinical studies in Parkinson's disease:  N. Ogawa et al., J. Med. 16, 525 (1985); H. Narabayashi et al., Adv. Neurol. 45, 593 (1986). Properties:  Crystals from ethanol and ether, mp 232-235° (dec).  [a]D20 -39° (c = 1 in 1N aq HCl).  Also cited as crystals from water and L-ascorbic acid, mp 229-232° (dec) (Ohashi).  [a]D20 -42.0° (c = 1 in 1N aq HCl). Melting point:  mp 232-235° (dec); mp 229-232° (dec) (Ohashi) Optical Rotation:  [a]D20 -39° (c = 1 in 1N aq HCl); [a]D20 -42.0° (c = 1 in 1N aq HCl) Therap-Cat:  Antiparkinsonian. Keywords:  Antiparkinsonian.  |