Title: Limonin
CAS Registry Number: 1180-71-8
CAS Name: Limonoic acid di-d-lactone
Synonyms: 8-(3-furyl)decahydro-2,2,4a,8a-tetramethyl-11
H,13
H-oxireno[
d]pyrano[4¢,3¢:3,3a]isobenzofuro[5,4-
f][2]benzopyran-4,6,13(2
H,5a
H)-trione; limonoic acid 3,19:16,17-dilactone
Molecular Formula: C26H30O8
Molecular Weight: 470.51
Percent Composition: C 66.37%, H 6.43%, O 27.20%
Literature References: Tetracyclic triterpenoid; bitter principle of citrus fruits. Isoln: Bernays,
Ann. 40, 317 (1841). Improved isoln and purification: P. G. Pifferi
et al., Ital. J. Food Sci. 5, 269 (1993). Structure: A. Melera
et al., Helv. Chim. Acta 40, 1420 (1957). Stereochemistry: D. Arigoni
et al., Experientia 16, 41 (1960); S. Arnott
et al., ibid. 49. Partial synthesis: C. Lüthy
et al., Helv. Chim. Acta 57, 1060 (1974). HPLC determn in citrus juice: W. W. Widmer,
J. Agric. Food Chem. 39, 1472 (1991). Review of chemistry: V. P. Maier
et al., ACS Symp. Ser. 143, 63-82 (1980); and removal of juice bitterness: R. F. H. Dekker,
Aust. J. Biotechnol. 2, 65 (1988).
Properties: Bitter crystals from methylene chloride + isopropanol or acetic acid, mp 298°. [a]D -128° (c = 1.21 in acetone). uv max: 207, 285 nm (e 7000, 38). Slightly sol in water, ether; sol in alcohol, glacial acetic acid.
Melting point: mp 298°
Optical Rotation: [a]D -128° (c = 1.21 in acetone)
Absorption maximum: uv max: 207, 285 nm (e 7000, 38)