Covalent anthocyanin-flavonol complexes from the violet-blue flowers of Allium 'Blue Perfume'.

Three covalent anthocyanin-flavonol complexes (pigments 1-3) were extracted from the violet-blue flower of Allium 'Blue Perfume' with 5% acetic acid-MeOH solution, in which pigment 1 was the dominant pigment. These three pigments are based on delphinidin 3-glucoside as their deacylanthocyanin and were acylated with malonyl kaempferol 3-sophoroside-7-glucosiduronic acid or malonyl-kaempferol 3-p-coumaroyl-tetraglycoside-7-glucosiduronic acid in addition to acylation with acetic acid. By spectroscopic and chemical methods, the structures of these three pigments 1-3 were determined to be: pigment 1, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-β-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-(3(III)-O-(β-glucopyranosyl(V))-β-glucopyranosyl(III))-4(II)-O-(trans-p-coumaroyl)-6(II)-O-(β-glucopyranosyl(IV))-β-glucopyranoside(II))-7-O-(β-glucosiduronic acid(VI)))) malonate; pigment 2, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-β-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-β-glucopyranosyl(III))-β-glucopyranoside(II))-7-O-(β-glucosiduronic acid(VI)))); and pigment 3, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-β-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-(3(III)-O-(β-glucopyranosyl(V))-β-glucopyranosyl(III))-4(II)-O-(cis-p-coumaroyl)-6(II)-O-(β-glucopyranosyl(IV))-β-glucopyranoside(II))-7-O-(β-glucosiduronic acid(VI)))) malonate.

The blue anthocyanin pigments from the blue flowers of Heliophila coronopifolia L. (Brassicaceae).

Six acylated delphinidin glycosides (pigments 1-6) and one acylated kaempferol glycoside (pigment 9) were isolated from the blue flowers of cape stock (Heliophila coronopifolia) in Brassicaceae along with two known acylated cyanidin glycosides (pigments 7 and 8). Pigments 1-8, based on 3-sambubioside-5-glucosides of delphinidin and cyanidin, were acylated with hydroxycinnamic acids at 3-glycosyl residues of anthocyanidins. Using spectroscopic and chemical methods, the structures of pigments 1, 2, 5, and 6 were determined to be: delphinidin 3-O-[2-O-(β-xylopyranosyl)-6-O-(acyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which acyl moieties were, respectively, cis-p-coumaric acid for pigment 1, trans-caffeic acid for pigment 2, trans-p-coumaric acid for pigment 5 (a main pigment) and trans-ferulic acid for pigment 6, respectively.

An unusual acylated malvidin 3-glucoside from flowers of Impatiens textori Miq. (Balsaminaceae).

Acylated malvidin 3-glucoside was isolated from the purple flowers of Impatiens textori Miq. as a major anthocyanin component along with malvidin 3-(6''-malonyl-glucoside). Its structure was elucidated to be malvidin 3-O-[6-O-(3-hydroxy-3-methylglutaryl)-beta-glucopyranoside] by chemical and spectroscopic methods.

Tetra-acylated cyanidin 3-sophoroside-5-glucosides from the flowers of Iberis umbellata L. (Cruciferae).

The structures of 11 acylated cyanidin 3-sophoroside-5-glucosides (pigments 1-11), isolated from the flowers of Iberis umbellata cultivars (Cruciferae), were elucidated by chemical and spectroscopic methods. Pigments 1-11 were acylated with malonic acid, p-coumaric acid, ferulic acid, sinapic acid and/or glucosylhydroxycinnamic acids. Pigments 1-11 were classified into four groups by the substitution patterns of the linear acylated residues at the 3-position of the cyanidin.

7-O-Methylated anthocyanidin glycosides from Catharanthus roseus.

Anthocyanins were isolated from orange-red flowers of Catharanthus roseus cv 'Equator Deep Apricot', and identified as rosinidin 3-O-[6-O-(alpha-rhamnopyranosyl)-beta-galactopyranoside] (1), and also 7-O-methylcyanidin 3-O-[6-O-(alpha-rhamnopyranosyl)-beta-galactopyranoside] (2) by chemical and spectroscopic methods. Pigment 1 was found to be a major anthocyanin in the flowers of this cultivar. By contrast, the distribution of rosinidin glycosides is very limited in plants, and reported only in the flowers of Primula.

Triacylated cyanidin 3-(3X-glucosylsambubioside)-5-glucosides from the flowers of Malcolmia maritima.

Three acylated cyanidin 3-(3(X)-glucosylsambubioside)-5-glucosides (1-3) and one non-acylated cyanidin 3-(3(X)-glucosylsambubioside)-5-glucoside (4) were isolated from the purple-violet or violet flowers and purple stems of Malcolmia maritima (L.) R. Br (the Cruciferae), and their structures were determined by chemical and spectroscopic methods.

Structure of anthocyanin from the blue petals of Phacelia campanularia and its blue flower color development.

The dicaffeoyl anthocyanin, phacelianin, was isolated from blue petals of Phacelia campanularia. Its structure was determined to be 3-O-(6-O-(4'-O-(6-O-(4'-O-beta-d-glucopyranosyl-(E)-caffeoyl)-beta-d-glucopyranosyl)-(E)-caffeoyl)-beta-d-glucopyranosyl)-5-O-(6-O-malonyl-beta-d-glucopyranosyl)delphinidin. The CD of the blue petals of the phacelia showed a strong negative Cotton effect and that of the suspension of the colored protoplasts was the same, indicating that the chromophores of phacelianin may stack intermolecularly in an anti-clockwise stacking manner in the blue-colored vacuoles.

Acylated peonidin glycosides from duskish mutant flowers of Ipomoea nil.

Five acylated peonidin glycosides were isolated from the pale gray-purple flowers of a duskish mutant in the Japanese morning glory (Ipomoea nil or Pharbitis nil) as major pigments, along with a known anthocyanin, Heavenly Blue Anthocyanin (HBA). Three of these were based on peonidin 3-sophoroside and two on peonidin 3-sophoroside-5-glucoside as their deacylanthocyanins; both deacylanthocyanins were acylated with caffeic acid and/or glucosylcaffeic acids. By spectroscopic and chemical methods, the structures of the former three pigments were determined to be 3-O-[2-O-(6-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-beta-D-glucopyranoside], 3-O-[2-O-(6-O-(3-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(4-O-(6-O-(3-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-trans-caffeoyl)-beta-glucopyranoside], and 3-O-[2-O-(6-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(4-O-(6-O-(3-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranoside] of peonidin.

Spontaneous mutations of the flavonoid 3'-hydroxylase gene conferring reddish flowers in the three morning glory species.

Among the Ipomoea plants, both Ipomoea nil and Ipomoea tricolor display bright blue flowers, and Ipomoea purpurea exhibits dark purple flowers. While all of these flowers contain cyanidin-based anthocyanin pigments, the mutants of I. nil, I.

Acylated anthocyanins from the blue-violet flowers of Anemone coronaria.

Five polyacylated anthocyanins were isolated from blue-violet flowers of Anemone coronaria 'St. Brigid'. They were identified as delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]-3'-O-[beta-D-glucuronopyranoside], and its demalonylated form, delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(2-O-tartaryl)malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]-3'-O-[beta-D-glucuronopyranoside], and its cyanidin analog as well as delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(2-O-(tartaryl)malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside].