15076-00-3Relevant articles and documents
Efficient and versatile synthesis of 5-O-acylquinic acids with a direct esterification using a p-methoxybenzyl quinate as a key intermediate
Oyama, Kin-Ichi,Watanabe, Noriyuki,Yamada, Tomomi,Suzuki, Masako,Sekiguchi, Yukiko,Kondo, Tadao,Yoshida, Kumi
, p. 3120 - 3130 (2015)
An efficient and versatile synthesis of 5-O-acylquinic acids from commercially available (-)-quinic acid was accomplished. We designed p-methoxybenzyl quinate as a key intermediate, and two problems, the esterification of the sterically hindered 5-OH group for the concise divergent synthesis and the low yield of the final deprotection step, were solved. For the first problem, we improved Tanabe's method, TsCl/NMI-mediated esterification using free carboxylic acids, by the addition of i-Pr2NEt. For the second problem, we established a TFA- or BCl3/C6HMe5-catalyzed deprotection reaction for the final deprotection step. 5-O-Acylquinic acids were synthesized in seven steps with 45-60% overall yield.
Synthesis of designed acylquinic acid derivatives involved in blue color development of hydrangea and their co-pigmentation effect
Toyama-Kato, Yuki,Kondo, Tadao,Yoshida, Kumi
, p. 239 - 254 (2008/03/12)
The blue sepal color of hydrangea may be developed by an unstable stipramolecular metal-complex pigment composed of delphinidin 3-glucoside (1), 5-O-caffeoylquinic acid (2) and 5-O-p-coumaroylquinic acid (3) as co-pigments and Al3+ in aqueous s
Essential structure of co-pigment for blue sepal-color development of hydrangea
Kondo, Tadao,Toyama-Kato, Yuki,Yoshida, Kumi
, p. 6645 - 6649 (2007/10/03)
Blue sepal-color of Hydrangea macrophylla might be due to a supramolecular metal-complex pigment consisting of delphinidin 3-glucoside (1), co-pigments (5-O-caffeoylquinic acid (2), and/or 5-O-p-coumaroylquinic acid (3)) and Al 3+ in an aqueous
