. Carotenoids. Carotenoids; Carotenoids. 138 CAROTENOID HYDROCARBONS OF KNOWN CONSTITUTION X CHq CHo \V -CH CH3 CH3 CH3 CH3 C II I I I /\ CH-C=CHCH=CH- C=CHCH=CHCH=C- CH=CHCH=C- CH=CH- C CHj HoC* C CHo \/ CHj For the properties and reactions of mutatochrome see p. '^-Carotene oxide' = Mutatochrome Dihydroxy-^-carotene C4oH5g02*: CHo CHo CHo CHo C OH CH3 CH3 CH3 CH, C /\/ I I I r /\ CHa C-CH=CH-C=CHCH=CH-C=CHCH=CHCH=C-CH=CHCH=C-CH=CH-C CHjj CH, C-OH H,C-C CH, CH2I Dihydroxy-j5-carotene ? CHj CH3 Dihydroxy-j3-carotene is formed during the careful oxidation of j3-carotene with aqueous N
. Carotenoids. Carotenoids; Carotenoids. 138 CAROTENOID HYDROCARBONS OF KNOWN CONSTITUTION X CHq CHo \V -CH CH3 CH3 CH3 CH3 C II I I I /\ CH-C=CHCH=CH- C=CHCH=CHCH=C- CH=CHCH=C- CH=CH- C CHj HoC* C CHo \/ CHj For the properties and reactions of mutatochrome see p. '^-Carotene oxide' = Mutatochrome Dihydroxy-^-carotene C4oH5g02*: CHo CHo CHo CHo C OH CH3 CH3 CH3 CH, C /\/ I I I r /\ CHa C-CH=CH-C=CHCH=CH-C=CHCH=CHCH=C-CH=CHCH=C-CH=CH-C CHjj CH, C-OH H,C-C CH, CH2I Dihydroxy-j5-carotene ? CHj CH3 Dihydroxy-j3-carotene is formed during the careful oxidation of j3-carotene with aqueous N-chromic acid ( atoms O). It crystalhses from a mixture of petrol and methanol in orange-red needles, 184° (Kuhn and Brock- MANN^^^). Dihydroxy-j3-carotene is easily adsorbed on aluminium oxide from benzene solution, but it is not adsorbed on calcium carbonate. (The lack of adsorption on calcium carbonate is unexpected for a compound assumed to contain two hydroxyl groups). Dihydroxy-^-carotene is easily soluble in benzene, chloroform and carbon disulphide, sparingly soluble in petrol, and insoluble in alcohols. On partition between petroleum ether and 90% methanol, it is found almost entirely in the upper layer. (The insolubility in alcohols and the epiphasic character of the compound are irreconcilable with the proposed formula). Solvent: Absorption maxima: Carbon disulphide 508 475 446 m/^ Chloroform 487 456 429 m^i Petrol 478 448 420 m^ Hexane 476 446 419 m/i Benzene 489 457 428 m/i Dihydroxy-j3-carotene shows vitamin A activity. Concerning the molecular formula of dihydroxy-^-carotene see R. Kuhn and H. Brockmann, Ber. 6y (1934) 1408 and Ann. 516 (1935) 99. References p. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Karrer, Paul, 1889-1971; Jucker, Ernst, 1918-. New York, Elsevier P
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