| Title:  Corynanthine CAS Registry Number:  483-10-3 CAS Name:  (16b,17a)-17-Hydroxyyohimban-16-carboxylic acid methyl ester Additional Names:  rauhimbine Molecular Formula:  C21H26N2O3 Molecular Weight:  354.44 Percent Composition:  C 71.16%, H 7.39%, N 7.90%, O 13.54% Literature References:  From bark of Pseudocinchona africana Chev., Corynanthe johimbe K. Schum., Rubiaceae and Rauwolfia serpentina (L.) Benth., Apocynaceae:  Raymond-Hamet, Compt. Rend. 212, 305 (1941); Jorio, Ann. Chim. Farm. 1939, 50, C.A. 33, 93069 (1939); Le Hir et al., Ann. Pharm. Fr. 11, 546 (1953); Hofmann, Helv. Chim. Acta 37, 314 (1954).  Identity with rauhimbine:  idem, ibid. 849.  Structure and stereochemistry:  Janot et al., Bull. Soc. Chim. Fr. 1952, 1085; 1961, 637. Properties:  Stout prisms from acetone, dec 225-226°.  [a]D19 -85° (c = 0.5 in pyridine).  uv max (methanol):  226, 283, 290 nm (log e 4.56, 3.87, 3.79).  Practically insol in water or petr ether.  Sol in 40 parts of boiling chloroform, in 60 parts of boiling benzene, in 20 parts of boiling ethyl acetate, in 5 parts of boiling alcohol. Optical Rotation:  [a]D19 -85° (c = 0.5 in pyridine) Absorption maximum:  uv max (methanol):  226, 283, 290 nm (log e 4.56, 3.87, 3.79)   Derivative Type:  O,N-Dibutyrylcorynanthine hydrochloride  Literature References:  Prepn:  Reiser et al., US 2975183 (1961 to Chemische Werke Albert). Properties:  Crystals from benzene, mp 208-210°. Melting point:  mp 208-210°   Derivative Type:  O,N-Dipropionylcorynanthine hydrochloride  Literature References:  Prepn:  Reiser et al., loc. cit. Properties:  Crystals from isopropanol, mp 236-237°. Melting point:  mp 236-237°   |