Title: Gambogic Acid
CAS Registry Number: 2752-65-0
CAS Name: (2Z)-2-Methyl-4-[(1R,3aS,5S,11R,14aS)-3a,4,5,7-tetrahydro-8-hydroxy-3,3,11-trimethyl-13-(3-methyl-2-butenyl)-11-(4-methyl-3-pentenyl)-7,15-dioxo-1,5-methano-1H,3H,11H-furo[3,4-g]pyrano[3,2-b]xanthen-1-yl]-2-butenoic acid
Molecular Formula: C38H44O8
Molecular Weight: 628.75
Percent Composition: C 72.59%, H 7.05%, O 20.36%
Literature References: Principal acidic component of gamboge from the latex of Garcinia hanburyi Hook. f., Guttiferae: Amorosa, Lipparini, Ann. Chim. (Rome) 45, 977 (1955). Structure: Ollis et al., Tetrahedron 21, 1453 (1965); Ahmed et al., J. Chem. Soc. C 1966, 772.
Properties: Golden, friable mass. [a]D20 -685° (methanol). uv max (ethanol): 217, 280, 291, 362 nm (e 26000, 16700, 17000, 14900).
Optical Rotation: [a]D20 -685° (methanol)
Absorption maximum: uv max (ethanol): 217, 280, 291, 362 nm (e 26000, 16700, 17000, 14900)
Derivative Type: Methyl ester monomethyl ether
Molecular Formula: C40H48O8
Molecular Weight: 656.80
Percent Composition: C 73.15%, H 7.37%, O 19.49%
Properties: Yellow prisms from methanol, mp 130-131°. [a]D22 -560° (c = 0.7 in chloroform). uv max (ethanol): 224, 299 nm (e 36000, 13600).
Melting point: mp 130-131°
Optical Rotation: [a]D22 -560° (c = 0.7 in chloroform)
Absorption maximum: uv max (ethanol): 224, 299 nm (e 36000, 13600)
Derivative Type: Pyridine salt
Molecular Formula: C43H49NO8
Molecular Weight: 707.85
Percent Composition: C 72.96%, H 6.98%, N 1.98%, O 18.08%
Properties: Orange needles from ether + petr ether, mp 147-149°. [a]D -550° (chloroform). uv max (ethanol): 291.5, 359.5 nm (e 22300, 18100).
Melting point: mp 147-149°
Optical Rotation: [a]D -550° (chloroform)
Absorption maximum: uv max (ethanol): 291.5, 359.5 nm (e 22300, 18100)
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