The absolute configuration of 1-(3',4'-dihydroxycinnamoyl)cyclopentane-2,3-diol from the amazonian tree Chimarrhis turbinata.
An antioxidant, 1-(3',4'-dihydroxycinnamoyl)cyclopentane-2,3-diol [or (E)-2,3-dihydroxycyclopentyl-3-(3',4'-dihydroxyphenyl)acrylate (1)], and two known trans- and cis-chlorogenic acid methyl esters were isolated from the ethanolic extract of the leaves of Chimarrhis turbinata. The relative configuration of 1 was determined by NMR and by comparison of the circular dichroic spectrum (CD) with those of the enantiomers of synthetic 3',4'-dimethoxycinnamoyl analogues. The absolute configuration of one of the synthetic enantiomers was determined using the CD exciton chirality method. This established the structure of naturally occurring 1 as (E)-2,3-dihydroxycyclopentyl-3-(3',4'-dihydroxyphenyl)acrylate.
Cardoso
Carmen Lucia
CL
NuBBE, Núcleo de Biossíntese, Bioensaios e Ecofisologia de Produtos Naturais, Instituto de Química, Universidade Estadual Paulista (UNESP), C.P. 355, 14800-900, Araraquara-SP, Brazil.
Bolzani
Vanderlan da Silva
Vda S
Silva
Dulce Helena Siqueira
DH
Ishii
Hideki
H
Berova
Nina
N
Nakanishi
Koji
K
D000975:Antioxidants / Q000737:chemistry*; D003517:Cyclopentanes / Q000737:chemistry*; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D014197:Trees / Q000737:chemistry*
C513458:1-(3',4'-dihydroxycinnamoyl)cyclopentane-2,3-diol; D000975:Antioxidants; D003517:Cyclopentanes