Title: Rhynchophylline
CAS Registry Number: 76-66-4
CAS Name: (7b,16E,20a)-16,17-Didehydro-17-methoxy-2-oxocorynoxan-16-carboxylic acid methyl ester
Additional Names: rhyncophylline; mitrinermine
Molecular Formula: C22H28N2O4
Molecular Weight: 384.47
Percent Composition: C 68.73%, H 7.34%, N 7.29%, O 16.65%
Literature References: From stems and roots of Uncaria rynchophylla Miq. [Ourouparia rynchophylla (Miq.)] Matsum, Rubiaceae: Kondo et al., J. Pharm. Soc. Jpn. 48, 54 (1928); from Mitragyna rotundifolia (Roxb.), Rubiaceae: Barger et al., J. Org. Chem. 4, 418 (1939). Structure: Seaton, Marion, Can. J. Chem. 35, 1102 (1957); 38, 1035 (1960). Stereochemistry: Nozoye, Chem. Pharm. Bull. 6, 309 (1958); Ban, Oishi, Tetrahedron Lett. 1961, 791; eidem, Chem. Pharm. Bull. 11, 441, 446, 451 (1963). Partial synthesis: Finch, Taylor, J. Am. Chem. Soc. 84, 1318, 3871 (1962). Total synthesis: Ban et al., Tetrahedron Lett. 1972, 2113.
Properties: Crystals from methanol, mp 216°; dl-form reported as colorless pillars from ethyl acetate-ether, mp 197-199° (Ban et al., loc. cit.). [a]D13 -14.7° (c = 2.5 in chloroform). pKa 6.4. uv max: 245, 280 nm (log e 4.24, 3.15). Sol in chloroform; moderately sol in acetone, alcohol, benzene; sparingly sol in ether, ethyl acetate. Practically insol in petr ether.
Melting point: mp 216°; mp 197-199° (Ban et al., loc. cit.)
pKa: pKa 6.4
Optical Rotation: [a]D13 -14.7° (c = 2.5 in chloroform)
Absorption maximum: uv max: 245, 280 nm (log e 4.24, 3.15) |