New Dimeric Compounds of Avenanthramide Phytoalexin in Oats
摘要:
[GRAPHICS]Avenanthramide B is an oat phytoalexin produced in response to pathogen attack and elicitation. We found the formation of new dimers (1-5) of avenanthramide B in elicited oat leaves. The dimers were synthesized by a reaction of peroxidase and avenanthramide B in the presence of hydrogen peroxide. The structures of 1-5 were determined by spectroscopic analyses, chemical derivatization, and N-15 labeling. Compound 1 was a dehydrodimer of avenanthramide B with a bisbutane lactam skeleton, while 2-4 were monohydrated dehydrodimers with butane lactam structures. Compound 5 was also a monohydrated dehydrodimer but with a tetrahydrofuran structure. All the compounds were classified into lignanamides that were formed by an 8 '-8 ' coupling reaction between two avenanthramide B units.
Avenanthramides in Oats (<i>Avena sativa</i> L.) and Structure−Antioxidant Activity Relationships
作者:Katarina Bratt、Kerstin Sunnerheim、Susanne Bryngelsson、Amelie Fagerlund、Lars Engman、Rolf E. Andersson、Lena H. Dimberg
DOI:10.1021/jf020544f
日期:2003.1.1
Eight avenanthramides, amides of anthranilic acid (1) and 5-hydroxyanthranilic acid (2), respectively, and the four cinnamic acids p-coumaric (p), caffeic (c), ferulic (f), and sinapic (s) acid, were synthesized for identification in oat extracts and for structure-antioxidant activity studies. Three compounds (2p, 2c, and 2f) were found in oat extracts. As assessed by the reactivity toward 1,1-dip
The phytoalexins of oat leaves: 4-3,1-benzoxazin-4-ones or amides?
作者:Leslie Crombie、Jayshree Mistry
DOI:10.1016/0040-4039(90)80150-k
日期:1990.1
Synthetic evidence is presented that the major phytoalexin of oat leaves is not the 4-H-3,1-benzoxazin-4-one previously reported, but the corresponding amide. Other oat and carnation phytoalexins are prepared.
Antimikrobiell wirksame Verbindungen zur Behandlung von Mundgeruch
申请人:Symrise GmbH & Co. KG
公开号:EP1886662A1
公开(公告)日:2008-02-13
Die Erfindung betrifft primär bestimmte Verwendungen einer Verbindung der Formel 1 oder von Mischungen aus zwei oder mehr unterschiedlichen Verbindungen der Formel 1, insbesondere zur Herstellung eines antimikrobiell wirkenden Mittels und Mittels gegen Mundgeruch sowie entsprechende Verfahren. Ferner betrifft die Erfindung bestimmte Produkte, insbesondere Mundhygieneprodukte, umfassend oder bestehend aus einer Verbindung der Formel 1 oder einer Mischung aus zwei oder mehreren unterschiedlichen Verbindungen der Formel 1
wobei für die Reste der Verbindung der Formel 1 bzw. jeder Verbindung der Formel 1 in der Mischung in der vorliegenden Beschreibung definiert sind.
Sensory-directed fractionation of extracts prepared from oat flour (Avena sativa L.) followed by LC-TOF-MS, LCMS/MS, and 1D/2D-NMR experiments revealed avenanthramides and saponins as the key phytochemicals contributing to the typical astringent and bitter off-taste of oat. Besides avenacosides A and B, two previously unreported bitter-tasting bidesmosidic saponins were identified, namely, 3-(O-alpha-L-rhamnopyranosyl(1 -> 2)-[beta-D-glucopyranosyl(1 -> 3)-beta-D-glucopyranosyl(1 -> 4)]-beta-D-glucopyranosid)-26-O-beta-D-glucopyranosyl-(25R)-furost-5-ene-3 beta,22,26-triol, and 3-(O-alpha-L-rhamnopyranosyl (1 -> 2)-[beta-D-glucopyranosyl(1 -> 4)]-beta-D-glucopyranosid)-26-O-beta-D-glucopyranosyl-(25R)-furost-5-ene-3 beta,22,26-triol. Depending on the chemical structure of the saponins and avenanthramides, sensory studies revealed human orosensory recognition thresholds of these phytochemicals to range between 3 and 170 mu mol/L.