Acylated anthocyanins from the violet-blue flowers of Orychophragonus violaceus

Three acylated cyanidin 3-sambubioside-5-glucosides (1-3) were isolated from the violet-blue flowers of Orychophragonus violaceus, and their structures were determined by chemical and spectroscopic methods. Two of those acylated anthocyanins (1 and 3) were cyanidin 3-O-[2-O-(2-O-(4-O-(6-O-(4-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-xylopyranosyl)-6-O-(4-O-(beta-D-glucopyranosyl)-trans-acyl)-beta-D-glucopyranoside]-5-O-(6-O-malonyl-beta-D-glucopyranoside)s, in which the acyl groups were p-coumaric acid for 1, and sinapic acid for 3, respectively. The last anthocyanin 2 was cyanidin 3-O-[2-O-(2-O-(4-O-(6-O-(4-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glucopyranosyl)-trans-caffeoyl)-beta-D-xylopyranosyl)-6-O-(4-O-(beta-D-glucopyranosyl)-trans-feruloyl)-beta-D-glucopyranoside]-5-O-beta-D-glucopyranoside. In these flowers, the anthocyanins 2 and 3 were present as dominant pigments, and 1 was obtained in rather small amounts.     

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. In the flowers of this plant, pigment 1 was determined to be cyanidin 3-O-[2-O-(2-O-(trans-sinapoyl)-3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-6-O-(trans-p-coumaroyl)-beta-D-glucopyranoside]-5-O-[6-O-(malonyl)-(beta-D-glucopyranoside) as a major pigment, and a minor pigment 2 was determined to be the cis-p-coumaroyl isomer of pigment 1. In the stems, pigment 3 was determined to be cyanidin 3-O-[2-O-(2-O-(trans-sinapoyl)-3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-6-O-(trans-p-coumaroyl)-beta-d-glucopyranoside]-5-O-(beta-D-glucopyranoside) as a major anthocyanin, and also a non-acylated anthocyanin, cyanidin 3-O-[2-O-(3-O-(beta-D-glucopyranosyl)-beta-D-xylopyranosyl)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside) was determined to be a minor pigment (pigment 4). In this study, it was established that the acylation-enzymes of malonic acid has important roles for the acylation of 5-glucose residues of these anthocyanins in the flower-tissues of M. maritima; however, the similar enzymatic reactions seemed to be inhibited or lacking in the stem-tissues.     

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. The structures of the latter two pigments were also confirmed as 3-O-[2-O-(6-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-beta-D-glucopyranoside]-5-O-beta-D-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]-5-O-beta-D-glucopyranoside of peonidin. The mutation affecting glycosylation and acylation in anthocyanin biosynthesis of Japanese morning glory was discussed.     

Anthocyanins from flowers of the orchids Dracula chimaera and D. cordobae

The main anthocyanins from flowers of the orchids Dracula chimaera and D. cordobae were isolated from a purified methanolic extract by preparative HPLC. Their structures were determined to be cyanidin 3-O-(6"-O-malonyl-beta-glucopyranoside), cyanidin 3-O-(6"-O-alpha-rhamnopyranosyl-beta-glucopyranoside), cyanidin 3-O-beta-glucopyranoside, peonidin 3-O-(6"-O-alpha-rhamnopyranosyl-beta-glucopyranoside) and peonidin 3-O-(6"-O-malonyl-beta-glucopyranoside). The structure determinations were mainly based on extensive use of 2D and 1D NMR spectroscopy, UV-vis spectroscopy and MS. The anthocyanin contents of species belonging to the subtribe Pleurothallidinae including genus Dracula Luer (Orchidaceae) have previously not been determined. The high content of anthocyanin rutinosides found in D. chimaera and D. cordobae (78 and 28% of the total anthocyanin content, respectively) differs from previously analysed orchid species, in which glucose is found as the only anthocyanin sugar moiety.     

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. Pigment 2 was found in smaller concentrations, but its aglycone, 7-O-methylcyanidin, has been reported only once before, from the fruit of mango.     

Two triacylated and tetraglucosylated anthocyanins from Ipomoea asarifolia flowers

Two triacylated and tetraglucosylated anthocyanins derived from cyanidin were isolated from the flowers of Ipomoea asarifolia and their structures elucidated using chemical, GC, MS and NMR methods (1H and 13C, TOCSY-1D, DQF-COSY, DIFFNOE and HMBC). These complex pigments were found to consist of cyanidin 3-O-[2-O-(6-O-E-caffeoyl-beta-D-glucopyranosyl)]-[6-O-[4-O-(6-O-E-3,5-dihydroxycinnamoyl-beta-D-glucopyranosyl)-E-caffeoyl]-beta-D-glucopyranosyl]-5-O-beta-D-glucopyranoside and cyanidin 3-O-[2-O-(6-O-E-p-coumaroyl-beta-D-glucopyranosyl)]-[6-O-[4-O-(6-O-E-p-coumaroyl-beta-D-glucopyranosyl)-E-caffeoyl]-beta-D-glucopyranosyl]-5-O-beta-D-glucopyranoside.     

Glucuronide triterpene saponins from Bersama engleriana

Five 3-O-glucuronide triterpene saponins (1-5) were isolated from the stem bark of Bersama engleriana Gurke along with two known saponins, polyscias saponin C and aralia saponin 15, and one major C-glycoside xanthone, mangiferin. The structures of the saponins were established mainly by means of spectroscopic methods (one- and two-dimensional NMR spectroscopy as well as FAB-, HRESI-mass spectrometry) as 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-betulinic acid (1), 3-O-[beta-D-glucopyranosyl-(1-->2)-[beta-D-galactopyranosyl-(1-->3)]-beta-D-glucuronopyranosyl]-oleanolic acid (2), 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucuronopyranosyl]-28-O-[beta-D-xylopyranosyl-(1-->6)-beta-d-glucopyranosyl]-oleanolic acid (3), 3-O-[beta-D-galactopyranosyl-(1-->3)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl]-oleanolic acid (4), and 3-O-[beta-d-glucopyranosyl-(1-->3)-beta-D-galactopyranosyl-(1-->3)-beta-D-glucuronopyranosyl]-28-O-[beta-d-xylopyranosyl-(1-->6)-beta-D-glucopyranosyl]-oleanolic acid (5).     

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].     

Further saponins from Meryta lanceolata

Five new oleanane-type saponins along with 11 known ones were isolated from the leaves and stems of Meryta lanceolata. The new saponins were characterised by spectroscopic analysis including FAMS, 1 and 2D NMR experiments and the results of hydrolysis as 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucuronopyranosyl] hederagenin 28-O-[alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranosyl] ester, 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucuronopyranosyl] oleanolic acid 28-O-[alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranosyl]ester, 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucuronopyranosyl] oleanolic acid 28-O-[alpha-l-rhamnopyranosyl-(1-->4)-beta-d-6-O-acetyl glucopyranosyl-(1-->6)-beta-d-glucopyranosyl]ester, 3-O-[beta-d-glucopyranosyl-(1-->3)-beta-d-glucopyranosyl-(1-->3)-alpha-l-arabinopyranosyl] oleanolic acid 28-O-[alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranosyl] ester and 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucuronopyranosyl] hederagenin, respectively.     

Acylated anthocyanins from leaves of Oxalis triangularis

The novel anthocyanins, malvidin 3-O-(6-O-(4-O-malonyl-alpha-rhamnopyranosyl)-beta-glucopyranoside)-5-O-beta-glucopyranoside (2), malvidin 3-O-(6-O-alpha-rhamnopyranosyl-beta-glucopyranoside)-5-O-(6-O-malonyl-beta-glucopyranoside) (3), malvidin 3-O-(6-O-(4-O-malonyl-alpha-rhamnopyranosyl)-beta-glucopyranoside)-5-O-(6-O-malonyl-beta-glucopyranoside) (4), malvidin 3-O-(6-O-(4-O-malonyl-alpha-rhamnopyranosyl)-beta-glucopyranoside) (5) and malvidin 3-O-(6-O-(Z)-p-coumaroyl-beta-glucopyranoside)-5-O-beta-glucopyranoside (6), in addition to the 3-O-(6-O-alpha-rhamnopyranosyl-beta-glucopyranoside)-5-O-beta-glucopyranoside (1) and the 3-O-(6-O-(E)-p-coumaroyl-beta-glucopyranoside)-5-O-beta-glucopyranoside (7) of malvidin have been isolated from purple leaves of Oxalis triangularis A. St.-Hil. In pigments 2, 4 and 5 a malonyl unit is linked to the rhamnose 4-position, which has not been reported previously for any anthocyanin before. The identifications were mainly based on 2D NMR spectroscopy and electrospray MS.     

Triterpenoid saponins with N-acetyl sugar from the bark of Albizia procera

Three (1,2,4) and one known (3) triterpenoid saponins were isolated from the bark of Albizia procera. The saponins were characterized as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl] echinocystic acid (1), 3-O-[alpha-L-arabinopyranosyl-(1-->2)-beta-D-fucopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl] echinocystic acid (2) and 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl] acacic acid lactone (4). Their structures were elucidated by 1D and 2D NMR experiments, FABMS as well as chemical means. Saponins 1 and 3 exhibited cytotoxicity against HEPG2 cell line with IC50 9.13 microg/ml and 10 microg/ml, respectively.     

27-Nor-triterpenoid glycosides from Mitragyna inermis

From the bark of Mitragyna inermis, two 27-nor-triterpenoid glycosides, named inermiside I (1) and II (2), were isolated and their structures determined based on extensive 2D-NMR and MS spectral analysis as 6-deoxy-beta-D-glucopyranosyl-[3-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]-pyrocincholate and 6-deoxy-beta-D-glucopyranosyl-pyrocincholate, respectively. In addition, the known quinovic acid (6), 3-O-[beta-D-glucopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl]-quinovoic acid (3),beta-D-glucopyranosyl-[3-O-(beta-D-glucopyranosyl)]-quinoviate (4) and cytotoxic 3-O-(beta-D-6-deoxy-glucopyranosyl)-quinovic acid (5) were also isolated.     

Triterpenoid saponins from Oreopanax guatemalensis

Seven oleanane-type saponins were isolated from the leaves and stems of Oreopanax guatemalensis, together with ten known saponins of lupane and oleanane types. The new saponins were respectively characterized as 3-O-alpha-L-arabinopyranosyl echinocystic acid 28-O-[alpha- L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester, 3-O-beta-D-glucopyranosyl 3beta-hydroxy olean-11,13(18)-dien-28-oic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta- D-glucopyranosyl]ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl]3beta-hydroxy olean-11,13(18)-dien-28-oic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]3beta, 23 dihydroxy olean-18-en-28-oic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-6-O-acetyl glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl] hederagenin 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-[beta-D-xylopyranosyl-(1-->2 )-]beta-D-glucopyranosyl]ester, 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl]hederagenin 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-[beta-D-glucopyranosyl-(1-->2)-]beta-D-glucopyranosyl] ester and 3-O-[alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl] hederagenin 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-[alpha-L-arabinofuranosyl-(1-->2)]-beta-D-glucopyranosyl] ester. The structures were determined by spectral analyses. The NMR assignments were made by means of HOHAHA, 1H-1H COSY, HMQC, HMBC spectra and NOE difference studies.     

Isolation and structure elucidation of flavonoid and phenolic acid glycosides from pericarp of hot pepper fruit Capsicum annuum L

Hot pepper fruits (Capsicum annuum L.) var. Bronowicka Ostra have been studied with regard to content of flavonoids and other phenolics. Nine compounds were isolated from pericarp of pepper fruits by preparative HPLC. Their structures were identified by chromatographic (analytical HPLC) and spectroscopic (UV, NMR) techniques. Two of the identified compounds, trans-p-ferulylalcohol-4-O-(6-(2-methyl-3-hydroxypropionyl) glucopyranoside and luteolin-7-O-(2-apiofuranosyl-4-glucopyranosyl-6-malonyl)-glucopyranoside were found for the first time in the plant kingdom. Additionally compounds: trans-p-feruloyl-beta-D-glucopyranoside, trans-p-sinapoyl-beta- D-glucopyranoside, quercetin 3-O-alpha-L-rhamnopyranoside-7-O-beta-D-glucopyranoside, luteolin 6-C-beta-D-glucopyranoside-8-C-alpha-L-arabinopyranoside, apigenin 6-C-beta-D-glucopyranoside-8-C-alpha-L-arabinopyranoside and luteolin 7-O-[2-(beta-D-apiofuranosyl)-beta-D-glucopyranoside] were found for the first time in pepper fruit Capsicum annuum L.     

Acetylated flavonol diglucosides from Meconopsis quintuplinervia

Four acetylated flavonol diglucosides, quercetin 3-O-[2'-O-acetyl-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranoside], quercetin 3-O-[2',6'-O-diacetyl-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranoside], isorhamnetin 3-O-[2'-O-acetyl-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranoside], and quercetin 3-O-[2'-O-acetyl-alpha-l-arabinopyranosyl-(1-->6)-beta-d-glucopyranoside], together with five known flavonol glycosides quercetin 3-O-beta-d-glucopyranoside, kaempferol 3-O-beta-d-glucopyranoside, quercetin 3-O-[beta-d-galactopyranosyl-(1-->6)-glucopyranoside], isorhamnetin 3-O-[beta-d-galactopyranosyl-(1-->6)-beta-d-glucopyranoside], and kaempferol 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucopyranoside] have been isolated from Meconopsis quintuplinervia. Their structures were determined using chemical and spectroscopic methods including HRFABMS, (1)H-(1)H COSY, HSQC and HMBC experiments.     

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. In a weakly acidic aqueous solution, phacelianin displayed the same blue color and negative Cotton effect in CD as those of the petals. However, blue-black colored precipitates gradually formed without metal ions. A very small amount of Al(3+) or Fe(3+) may be required to stabilize the blue solution. Phacelianin may take both an inter- and intramolecular stacking form and shows the blue petal color by molecular association and the co-existence of a small amount of metal ions. We also isolated a major anthocyanin from the blue petals of Evolvulus pilosus and revised the structure identical to phacelianin.     

Saponins and acylated saponins from Dizygotheca kerchoveana

Four new triterpenoid saponins were isolated from the leaves and stem of branches of Dizygotheca kerchoveana along with seven known ones. The new saponins were respectively characterized as 3-O-[beta-D-glucopyranosyl-(1-->3)]-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl echinocystic acid, 3-O-[beta-D-glucopyranosyl-(1-->3)]-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl echinocystic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester, 3-O-[beta-D-3-O-trans-p-coumaroyl-glucopyranosyl-(1-->3)]-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl echinocystic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester and 3-O-[beta-d-3-O-cis-p-coumaroyl-glucopyranosyl-(1-->3)]-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl echinocystic acid 28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester. Their structures were elucidated by 1D and 2D NMR experiments, FAB-MS as well as chemical means.     

Acylated anthocyanins from red radish (Raphanus sativus L.)

Twelve acylated anthocyanins were isolated from the red radish (Raphanus sativus L.) and their structures were determined by spectroscopic analyses. Six of these were identified as pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-beta-D-glucopyranosyl]-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-caffeoyl-2-O-(6-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-p-coumaroyl-2-O-(6-(E)-caffeoyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-(6-(E)-caffeoyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-p-coumaroyl-2-O-(6-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), and pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-(2-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside).     

Acetylated glucuronide triterpene bidesmosidic saponins from Symplocos glomerata

Nine new bidesmosidic 3-O-glucuronide oleanane triterpenoid saponins were isolated from the stem bark of Symplocos glomerata King along with two known saponins, salsoloside C and copteroside E, and two major lignans, (-)-pinoresinol and (-)-pinoresinol-4'-O-beta-D-glucopyranoside. The structures of the new saponins were established using one- and two-dimensional NMR spectroscopy and mass spectrometry as, 3-O-[beta-D-xylopyranosyl(1-->4)-[2-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[beta-D-xylopyranosyl(1-->4)-[3-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[beta-D-xylopyranosyl (1-->4)-[2,3-O-diacetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[alpha-L-arabinopyranosyl(1-->4)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[alpha-L-arabinopyranosyl (1-->4)-[2-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[[beta-D-xylopyranosyl (1-->2)]-[beta-D-xylopyranosyl (1-->4)]-[3-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[[beta-D-glucopyranosyl (1-->2)]-[beta-D-xylopyranosyl (1-->4)]-[3-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[[beta-D-glucopyranosyl (1-->2)]-[alpha-L-arabinofuranosyl (1-->4)]-[3-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, and 3beta-O-[beta-D-xylopyranosyl(1-->4)-[2-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-morolic acid. The EtOH and EtOAc extracts of the stem bark showed no cytotoxic activity. At a concentration of 370 microg/ml, the saponin mixture showed haemolytic activity and caused 50% haemolysis of a 10% suspension of sheep erythrocytes.     

Components of protocyanin, a blue pigment from the blue flowers of Centaurea cyanus

The components involved in the formation of protocyanin, a stable blue complex pigment from the blue cornflower, Centaurea cyanus, were investigated. Reconstruction experiments using highly purified anthocyanin [centaurocyanin, cyanidin 3-O-(6-O-succinylglucoside)-5-O-glucoside], flavone glycoside [apigenin 7-O-glucuronide-4'-O-(6-O-malonylglucoside)] and metals, Fe and Mg, showed the presence of another factor essential for the formation of protocyanin. The unknown factor was revealed to be Ca. Reconstructed protocyanin using anthocyanin, flavone, Fe, Mg, and Ca was identical with protocyanin from nature in UV-Vis and CD spectra, and was isolated as crystals for the first time. In addition, substitution of the metal components in protocyanin with other metals was also examined.