著者

福井 祐子 田中 良和 久住 高章 岩下 孝 益田 勝吉 野本 享資

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

vol.42, pp.55-60, 2000

被引用文献数

1

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Rose breeders have failed to make blue roses. This has been attributed to the lack of blue pigment in the petals. We revealed that mauve rose such as "M'me.Violet" and "Lavande" contain a small amount of blue pigment other than a red anthocyanin, cyanidin 3,5-diglucoside. The major blue pigment of the rose named Rosacyanin A and the minor red one was named Rosacyanin B. The structures of these pigments were elucidated. A high-resolution mass spectrometry showed that Rosacyanin B had the molecular weight of 419.0409 and molecular formula of C_<22>H_<11>O_9. The NMR data showed that Rosacyanin B had an extremely unique structure whose C-1 position of gallic acid is bound to the C-4 position of cyanidin by C-C bond formation. (Fig.2) Rosacyanin A has λ max 590nm (MeOH) of the ultraviolet and visible absorption spectrum, and a molecular formula of C_<56>H_<37>O_<31> which is calculated from the molecular weight of 1205.1319 obtained from high-resolution mass spectrometry. As a result of the observation of the isotope shift by the DH exchange of the solvent using a coaxial sample tube in ^<13>C NMR, it was found that the 3-position of flavylium of Rosacyanin B is bonded to the hexahydroxydiphenoyl part of Tellimagrandin II which is a kind of ellagitannin with ether linkage. (Fig.4) To our knowledge, this is the first report of the compound whose gallic acid binds to C-4 position of polyhydroxyflavylium. The only similar compound which binds gallic acid to catechin was obtained from Burkea africana and Peltophorum africanum. The dream of blue roses will come true if we can accumulate Rosacyanin A in rose petals.

著者

岩下 孝

出版者

公益社団法人 日本化学会

雑誌

日本化学会誌(化学と工業化学) (ISSN:03694577)

巻号頁・発行日

vol.1986, no.11, pp.1601-1603, 1986-11-10 (Released:2011-05-30)

参考文献数

1

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The specific line-broadening effects caused by the addition of a small amount of acid were noted for some 'H-NMR of stemotinine [1] and isostemotinine [2]. The molecular structure of [1] has recently been established by X-ray analysis, we could correlate the line-broadening effect with the stereochemistry of the spiro-lactone moieties of [1] and [2]. Since line-broadening was found to be induced by partial salt formation of the tertiary amino group, it may be widely observed with other alkaloids and may afford a versatile supplementary tool for the stereochemical study of alkaloids.

著者

岩下 孝 関谷 紀子

出版者

(財)サントリー生物有機科学研究所

雑誌

基盤研究(C)

巻号頁・発行日

1996

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膜タンパク質に^<19>F固体NMR法を適用して構造解析を行うためにフッ素化トリプトファンのバクテリオロドプシンへの取込み実験を計画した。バクテリオロドプシンには8個のトリプトファンしか含まれていないが、化学シフトの重なりが予想されるので分散性を期待して4-F、5-F、6-F-トリプトファンについて取込み実験を行い、それぞれのトリプトファンが標識されたフッ素化バクテリオロドプシンを得た。その中で6-F-トリプトファンを含むバクテリオロドプシンはスクロースグラジエントやMALDI-TOF MSの挙動からタンパク質と膜との複合的な構造に根本的な違いがある可能性が示唆された。そこで、これら3種のF-トリプトファン含有バクテリオロドプシンのX線回折実験およびCDスペクトルの測定を行ったところ、6-F-トリプトファンを含むバクテリオロドプシンについてはX線回折像が全く得られず、またCDスペクトルからも非結晶性であることが明かとなった。タンパク質内での核間距離の測定を目指してレチナールクロモフォアのシクロヘキセニル部分をCF3基を持つベンゼン環に置換した合成レチナールを調製し、5-F-トリプトファンを含むオプシンとの再構成を行った。トリプトファンのインドール環上にあるフッ素と天然レチナールと置き換えた合成レチナールのCF3基との間に双極子-双極子相互作用による磁化移動が起こるかどうか実験を行った。1次元RFDR実験と2次元CP_EXCY実験によって磁化移動が起っていることが示唆されたので、2次元MELODRAMA実験を行ったところ、両者の化学シフトが交差する位置にダイアゴナルピークとは逆位相のクロスピークを観測し磁化移動が起っていることを確認した。

著者

福井 祐子 岩下 孝 浅見 純生 野中 裕司 前田 満 橋本 文雄 木曽 良信

出版者

天然有機化合物討論会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

no.50, pp.475-480, 2008-09-01

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Oolong tea is a semi-fermented tea, which has been manufactured from leaves of Camellia sinensis (L) O. Kuntze, same as non-fermented Japanese or Chinese green teas. Major components of fresh tea leaves are caffeine and catechins such as epigallocatechin-3-O-gallete (EGCG). During the fermentation process, polyphenol oxidase (PPO) in tea leaves oxidizes the catechins into theasinensin and oolongtheanin. In addition, oolonghomobisflavans are known as condensation products of catechins by heat treatment. The aim of this study is to quantify these minor polymerized polyphenols by LC-MS/MS, and address their biological activities. Quantification of polyphenols by LC-MS/MS Theasinensin (TSN), oolongtheanin gallate (OTNG), and oolonghomobisflavan (OHBF) were synthesized from EGCG. Two new trimers and tetramers of oolonghomobisflavan were synthesized along the previous synthesis method of OHBF, and then their structures were determined by MS and NMR spectroscopy. Quantification of these compounds was performed by LC-MS/MS in the mode of multiple reaction monitoring (MRM). Compounds other than TSN-A were of small quantities in oolong tea leaves. Quantification of polymerized polyphenols was not performed with HPLC UV monitoring, but by LC-MS/MS method. Nine kinds of oolong teas in different fermentation levels were extracted and analyzed. The very small amount of trimers and tetramers of OHBF were included in "Black oolong tea", therefore, it was necessary to make concentrated solutions of these by column separation, and quantified the real amount by analyzing them. Biological activities of polymerized polyphenols Pancreatic lipase inhibitory activity of oolong tea polymerized polyphenols (OTPP) and some catechin dimmers have been already reported. In this study, new trimers and tetramers also exhibited strong inhibitory activity. Besides OTPP, the polymerized polyphenols, TSN, OTNG, and OHBF also have α-glucosidase inhibitory activity. These results suggest that oolong tea prevents the elevations of triglyceride in blood from meal fat, as well as inhibit the absorption of sugars derived from carbohydrates.