4807. Hydroquinine
Nomenclature
CAS number: 522-66-7
(8α,9R)-10,11-Dihydro-6′-methoxycinchonan-9-ol; dihydroquinine. C20H26N2O2; mol wt 326.43.
C 73.59%, H 8.03%, N 8.58%, O 9.80%.
Description and references
An alkaloid of cinchona, found in quinine sulfate mother liquors. Stereoisomeric with hydroquinidine, q.v. Usually prepd by careful hydrogenation of quinine: Heidelberger, Jacobs, J. Am. Chem. Soc. 41, 819 (1919). Total synthesis: Rabe et al., Ber. 64B, 2487 (1931). Synthesis of isomers: Rubtsov, J. Gen. Chem. USSR 9, 1493 (1939), C.A. 34, 2850 (1940); ibid. 13, 593, 702 (1943), C.A. 39, 705 (1945). LC determn in quinine beverages: L. P. Valenti, J. Assoc. Off. Anal. Chem. 68, 782 (1985).
Properties
Needles from ether or benzene, mp 172°. [α]D18 142° (alc); [α]D20 236° (c = 0.82 in 0.1N H2SO4). pK1 = 5.33. Freely sol in acetone, alcohol, chloroform, ether, petr ether; fairly sol in ammonia water. Almost insol in water (290 mg/l).Derivative
Hydrochloride hemihydrate.C20H27ClN2O2.H2O; mol wt 371.90.
C 64.59%, H 7.59%, Cl 9.53%, N 7.53%, O 10.76%.
Properties
Prisms from water, mp 208° (Heidelberger). [α]D21 124° (c = 1.1). pH of 0.005 molar soln 5.85. Freely sol in water, alcohol, methanol, acetone. Almost insol in ether. Crystallizes also with 2 mols H2O. Infrared spectrum: J. Suszko, Z. Dega-Szafran, Bull. Acad. Pol. Sci. Ser. Sci. Chim. 12, 607 (1964), C.A. 62, 7819b (1965).Therapeutic Category
Depigmentor.
Keywords
Depigmentor