The composition of a flavonoid complex from Larix wood (Pinaceae). The stereochemistry of dihydroquercetin

Stereospecific high‐performance liquid chromatography of taxifolin, applications in pharmacokinetics, and determination in tu fu ling (Rhizoma smilacis glabrae) and apple (Malus × domestica)

“…When the pure (2R3R)-(+) enantiomer was analyzed, it also eluted around 82 min, confirming that the taxifolin-3-O-rhamnoside has this configurational state. Based on literature information (Kolesnik et al, 2007), and comparing our CD data obtained with published work (Baderschneider and Winterhalter, 2001;Lee et al, 2003;Li et al, 2002;Morimura et al, 2006;Sakushima et al, 2002), we were able to identify the enantiomers of taxifolin which typically eluted in the following order: (2S3R)-(+) (~68 min), (2S3S)-(−) (73 min), (2R3R)-(+) (82 min) and (2R3S)-(−) (126 min) [ Fig. 2(b)].…”

“…Identification or separation of the four taxifolin enantiomers has only been attained when taxifolin is glycosylated (Chen et al, 2007;Nonaka et al, 1987). Identification of the four taxifolin enantiomers was reported by Kielhmann and Slade, and Kolesnik et al, but enantio-isolation was not accomplished by Kielhmann and Slade (Kiehlmann and Slade, 2003) and no chromatographic or stereospecific data has been made available by Kolesnik et al (Kolesnik et al, 2007).…”

“…Racemic taxifolin has been previously identified in several plants using an array of analytical methods including liquid chromatography (LC; Chen et al, 2007;Geodakyan et al, 1992;Haraguchi et al, 1996), gas chromatography (Willfor et al, 2003), nuclear magnetic resonance (NMR) spectrometry (Exarchou et al, 2003), circular dichroism (CD; Nonaka et al, 1987), and mass spectrometry (MS; Prati et al, 2007). Few studies have examined the chiral nature of taxifolin using LC (Japón-Luján and Luque de Castro, 2007;Lepri et al, 1997;Ng et al, 2002;Ohmura et al, 2002) and NMR spectrometry (Kolesnik et al, 2007;Kolesnikov and Gins, 2001;Lundgren and Theander, 1988). Ng et al acknowledged the importance of developing methods to recognize taxifolin enantiomers in natural products, but failed to achieve total separation of taxifolin enantiomers using a methylated β-cyclodextrin chiral stationary phase in LC (Ng et al, 2002).…”

“…Ng et al acknowledged the importance of developing methods to recognize taxifolin enantiomers in natural products, but failed to achieve total separation of taxifolin enantiomers using a methylated β-cyclodextrin chiral stationary phase in LC (Ng et al, 2002). The available studies that have considered enantio-separation of taxifolin did not separate the four enantiomers, but only two enantiomers (Japón-Luján and Luque de Castro, 2007;Kiehlmann and Edmond, 1995;Kolesnik et al, 2007;Lepri et al, 1997;Lundgren and Theander, 1988;Ohmura et al, 2002). Studies with taxifolin glycosides have accomplished the enantio-separation or identification of one (Lundgren and Theander, 1988;Yi et al, 1998), two (Chen et al, 2007;Hosoi et al, 2006) or four (Nonaka et al, 1987) of its enantiomers via HPLC (Chen et al, 2007), NMR spectrometry (Hosoi et al, 2006;Lundgren and Theander, 1988;Nonaka et al, 1987;Yi et al, 1998), CD (Nonaka et al, 1987) and MS (Du et al, 2005).…”