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The major red color component from Carthamus tinctorius was efficiently isolated by a modified new method of traditional procedure and column chromatographic technique. After removing yellow pigments by washing Carthamus flowers with water and methanol, the red pigment was extracted with 0.5 M Na₂CO₃, and precipitated with aqueous citrate. The pigment was further isolated and purified with cellulose adsorption and Sephadex LH-20 column chromatography. The purified red pigment was decomposed at about 300℃, and its R_f value on silica gel in BAW(n-BuOH : HOAc : H₂O=4 : 1 : 5) was 0.56. UV/Vis spectrum of the red pigment showed λ_(max) at 519, 372, 311, 244 ㎚ and its IR spectrum showed wide and strong absorption near 3400 cm(-2) indicating characteristic hydroxyl groups. ¹H and ^(13)C NMR spectra showed that it contained two enolized β-triketone, two p-hydroxycinnamoyl moieties, a methine, and two glucosyl moieties. On the basis of spectroscopic evidences, the chemical structure of the red pigment was identified as 6-β-D-glucopyranosyl-2-[[3-β-D-glucopyranosyl-2,3,4-trihydroxy-5-[3´-(4$quot;-hydroxyphenyl)-1´-oxo-2´-propenyl]-6-oxo-1,4-cyclohexadien-1-yl]methylene]-5,6-dihydroxy-4-[3´-(4$quot;-hydroxyphenyl)-1´-oxo-2´-propenyl]-4-cyclohexene-1,3-dione, carthamin.
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