Malvin chloride

The effects of catechin, epicatechin, procyanidin B2, caffeic acid, / -coumaric acid, myricetrin, and quercetrin on the color intensity and stability of malvidin 3-glucoside at a molar ratio of 1 1 under conditions similar to red wine were evaluated. " Flavan 3-ols appeared to have the lowest protective effects and flavonols the highest strong color changes were visually perceptible. " In the complexation of malvin chloride and natural polyphenols, flavonol glycosides by far exerted the best protector effect. ... 

Compounds 1 = 4-hydroxycoumarin 2 = umbelliferon 3 = 4-methyl-esculetin 4 = isopimpinellin 5 = esculin 6 = flavone 7 = a-naphtoflavone 8 = kaempferol 9 = quercetin 10 = isoquercitrin 11 = robinetin 12 = robinin 13 = myricetin 14 = luteolin 7-O-glucoside 15 = rutin 16 = hes-peretin 17 = hespiridin 18 = naringin 19 = pelargonin chloride 20 = polargonin chloride 21 = malvin chloride. 

Thompson KM, Spirito M, Griffith WP. Mechanism of bleaching by peroxides. Part 4—kinetics of bleaching of malvin chloride by hydrogen-peroxide at low pH and its catalysis by transition metal-salts. J Chem Soc Farad Trans 1996 92 2535. 

Fig. 1.4 represents the UV-visible spectra of a pH 1 aqueous solution containing malvin chloride with ferric chloride in excess. Three characteristic features had emerged from that experiment (1) the equilibrium state is reached only after 17 h (25 °C) (2) two isosbestic points appear at 284 and 362 nm and (3) during the kinetic course, the flavylium... 

Fig. 1.4 Time evolution of the UV-visible absorption of malvin chloride at pH 1, in the presence of an excess of ferric chloride (George et al., 1999).

Fig. 1.6 H NMR spectra of malvin chloride at 25 °C (a) pure malvin chloride, (b) malvin with ferric chloride after 1 h, and (c) at equilibrium after a full day. Symbols indicate the different forms (see Fig. 1.3) ( ) flavylium cation, ( /°) hemiketal, (A) 5-retrochalcone, ( ) Z-retrochalcone, and ( ) Z-chalcone-iron complex.

FIGURE 6 Absorption spectra recorded immediately after dissolving an anthocyanin (malvin chloride) in buffers of pH 2, 6, and 10. The absorption peaks at pH 6 and 10 disappeared within 1 to 3 hr. (Adapted from Brouillard, R. (1982). In Anthocyanins as Food Colors (P. Markakis, ed.). Academic Press, New York.]... 

Malvin (primulidin, malvidin 3,S-di-0-glucoside). C29H350n , Mr 655.59, mp. of the chloride 165 °C (decomp.), reddish brown prisms and needles with green luster. Widespread occurrence as flower pigments. Lit Karrer, No. 1749ff. Phytochemistry 33, 1227 (1993). -[CAS 16727-30-3 (chloride)]... 

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