8 - Hydroxy Geraniol, 8 - Hydroxyl Neroli, 8 - Hydroxy-linalool And Its Derivatives Of The Preparation And Characterization Of Damascus Rose In Several Chemical Ingredients

Monoterpenes have two prenyl units in structure, containing 10 carbon atoms. They are the main components of plant volatile oil. According to the skeleton structures, monoterpenes can be divided into two types:acyclic type and cyclic-type. Oxygen-containing monoterpene derivatives, such as 8-hydroxygeraniol,8-hydroxynerol and 8-hydroxylinalool, etc. have strong biological activity and are rich in aroma, they are the important materials of pharmaceutical, cosmetic and food industries. Moreover,8-hydroxygeraniol is not only a key intermediate of monoterpene biosynthesis, but also plays a critical role in the biosynthetic pathway for the monoterpene-indole alkaloids, such as reserpine and camptothecin which have wide ranges of medicinal values. In this study we synthesized three oxygen-containing acyclic monoterpene derivatives by oxidation of geraniol, nerol and linalool with SeO2/ter-buty hydroperoxide, then reduction with NaBH4. 8-hydroxygeraniol, 8-hydroxynerol and 8-hydroxylinalool were obtained by this strategy. The acetylated and benzoylated derivatives of these alcohols were prepared by respective acetylation and benzoylation. Furthermore, all these compounds were characterized by GC-EI-MS and LC-ESI-MS respectively and the results showed that only in ESI-MS, the signals of molecular ions of these compounds were able to be clearly observed. This effort provides a useful tool for the study of biosynthesis of monoterpenoids in plants.Rose (Rosa) belongs to the family of the Rosaceae and is planted world widely, mainly in the northern hemispheric countries, such as Bulgaria, Turkey, Morocco, France, Russia, etc. It is also cultivated in our country. There are many kinds of roses among which Rosa damascena contains abundant monoterpenes. What we used in this study is the R. damascena planted in Weinan, Shaanxi Province. The flowers of plant were extrcated with organic solvents, isolated with solica gel chromatography and the fractions that might contain the oxidized acyclic monoterpenes, eg.8-hydroxygeraniol,8-hydroxynerol and 8-hydroxylinalool, were analysed with GC-MS to find out where they located. In the course of the study, two more compounds were also purified and elucidated. The work has not only provided a new method for the determination of the main aromatic components of Rosa damascena, but also built up an important foundation for the study of biosynthesis of monoterpenoids in the plant...