Ritsuko Hara

Floral anthocyanins in wild taxa of Petunia (Solanaceae)

The flowers of 20 native taxa of Petunia (Solanaceae) were investigated by HPLC for the occurrence of anthocyanins. The investigation revealed the presence of at least 24 anthocyanins in their flowers, of which 18 known anthocyanins isolated from the flowers of P. exserta, P. guarapuavensis, P. integrifolia, P. occidentalis, and P. reitzii were fully identified by chemical and spectral methods to be 3-glucoside of delphinidin; 3-rutinosides of cyanidin, delphinidin, and petunidin; 3-rutinoside-5-glucosides, 3-trans and -cis-p-coumaroylrutinoside-5-glucosides, and 3-trans-caffeoylrutinoside-5-glucosides of delphinidin, petunidin, and malvidin; and 3-transcaffeoylglucosyl-trans-(caffeoyl or p-coumaroyl) rutinoside-5-glucosides of malvidin. Six novel anthocyanins were isolated from the flowers of P. occidentalis, and their structures were identified to be 3-glucosyl p-coumaroylrutinoside-5-glucosides and 3-glucosylcaffeoylrutinosides of petunidin and malvidin, and also 3-caffeoylglucosylcaffeoylrutinoside-5-glucoside and 3-caffeoylglucosyl p-coumaroylrutinoside-5-glucoside of petunidin. Out of the six pigments, petunidin 3-glucosyl p-coumaroylrutinoside-5-glucoside was unambiguously determined by spectral methods to be petunidin 3-O-[6-O-(4-O-(4-O-(β-d-glucopyranosyl)-trans-p-coumaroyl)-α-l-rhamnopyranosyl)-β-d-glucopyranoside]- 5-O-[β-d-glucopyranoside]. The 20 native taxa of Petunia could be placed into four groups (A, B, C, and D) with one further into five subgroups (D1–D5) regarding their constituents and contents of major anthocyanins and also their pigment biosynthesis with respect to the blocks or inhibitors of the hydroxylation, glucosylation, and acylation reactions in them. The use of anthocyanins as taxonomic markers in the genus Petunia is discussed in relation to the flower colour and possible pollination vectors.

A total synthesis of manzamine C and its geometrical isomer

Abstract Manzamine C (1) has been synthesized from silyloxyscetylene (3) along the line: 4→5→8→18→1. The overall yields is 21%. Thr β-carboline segment (11) was obtained by the Bischler-Napieralski reaction of 14 followed by dehydregenation. By the similar procedure, the trans isomer 2 and dihydromanzamine C (21) have been synthesized.

Differences in the floral anthocyanin content of red petunias and Petunia exserta.

In order to resolve a conflict between previous papers regarding the floral anthocyanins of red flowers of Petunia exserta, a naturally occurring species, the HPLC profile of this species was compared with that of commercial red garden petunias. Both HPLC profiles extremely superficially resemble each other in terms of relative amounts and retention times of the major anthocyanins. However, co-elution on HPLC of the mixed sample resulted in clear separation of the components. Three major anthocyanins in red petunias were determined to be cyanidin 3-sophoroside, cyanidin 3-glucoside and peonidin 3-glucoside, which exhibited similar behaviors on HPLC to delphinidin 3-glucoside. delphinidin-3-rutinoside and petunidin 3-rutinoside, respectively, the major floral anthocyanins of P. exserta.

Acylated cyanidin glycosides in the red-purple flowers of Phalaenopsis

Abstract Four acylated anthocyanins were isolated from the red-purple flowers of Phalaenopsis hybrid cultivars as major anthocyanins and their distribution was investigated in the flowers of five species; P. equestris, P. intermedia, P. leucorrhoda, P. sanderiana and P. schilleriana cultivar ‘Pink Butterfly’. These four pigments were based on cyanidin 3,7,3′-triglucoside as their deacylanthocyanin, which was acylated with two molecules of hydroxycinnamic acid and/or one molecule of malonic acid. Two anthocyanins were characterized as cyanidin 3-O-[6-O-( malonyl )-β- d -glucopyranoside ]-7,3′-O-di-[6-O-(trans- sinapyl )-β- d -glucopyranoside ] and its demalonyl derivative by spectral and chemical methods.

Acylated delphinidin 3-rutinoside-5-glucosides in the flowers of Petunia reitzii.

Two acylated anthocyanins were isolated from selected individuals of Petunia reitzii, and identified to be delphinidin 3-O-[6-O-(4-O-(4-O-(6-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-tr ans-p-coumaroyl)-alpha-L-rhamnopyranosyl)-beta-D-glucopyranoside]- 5-O-[beta-D-glucopyranoside] and delphinidin 3-O-[6-O-(4-O-(4-O-(beta-D-glucopyranosyl)-trans-p-coumaroyl)-alph a-L-rhamnopyranosyl)-beta-D-glucopyranoside]-5-O-[beta-D-glucopyranoside ]. Nine known anthocyanins were also identified.

Acylated Peonidin 3-Rutinoside-5-glucosides from Commercial Petunia Cultivars with Pink Flowers

Two new acylated peonidin glycosides and three known acylated or non-acylated peonidin glycosides were identified in the flowers of 17 commercial pink petunias: peonidin 3-O-[6-O-(4-O-(4-O-(6-O-(trans-caffeoyl)-β-D-glucopyranosyl)-trans-p-coumaroyl)-α-L-rhamnopyranosyl)-β-D-glucopyranoside]-5-O-[β-D-glucopyranoside], peonidin 3-O-[6-O-(4-O-(4-O-(β-D-glucopyranosyl)-trans-p-coumaroyl)-α-L-rhamnopyranosyl)-β-D-glucopyranoside]-5-O-[β-D-glucopyranoside], peonidin 3-p-coumaroylrutinoside-5-glucoside, peonidin 3-caffeoylrutinoside-5-glucoside, and peonidin 3-rutinoside-5-glucoside.

Acylated malvidin 3-rutinosides in dusky violet flowers of Petunia integrifolia subsp. inflata

Abstract A new acylated anthocyanin was isolated from a strain of Petunia integrifolia subsp. inflata with dusky violet flowers (B1204d), and identified as malvidin 3- O -[6- O -(4- O -(4- O -(6- O -( trans -caffeoyl)- β - d -glucopyranosyl)- trans - p -coumaroyl)- α - l -rhamnopyranosyl)- β - d -glucopyranoside] as a major pigment. Also, two known pigments were found in these flowers, and determined to be malvidin 3-caffeoylrutinoside and 3- p -coumaroylrutinoside.