Sinapyl aldehyde

Foumand, D. Cathala, B. Lapierre, C. Initial steps of the peroxidase-catalyzed polymerization of coniferyl alcohol and/or sinapyl aldehyde capillary zone electrophoresis study of pH effect. Phytochemistry 2003, 62, 139-146. 

Santalum album L. S. myrtifolium Roxb. S. verum L. Tan Xian (Sandalwood) (heartwood) Alpha-santalol, beta-santalol, alpha-santalene, beta-santalene, santene, alpha-santenone, alpha-santenol, santalone, santalic acid, teresantalic, isovaleraldehyde, teresantalol, tricycloekasantal, santalin, deoxysantalin, sinapyl aldehyde, caniferyl aldehyde, syringic aldehyde.33 Treat stomachache. 

Pomar, F., Merino, F., and Ros Barcelo, A., 2002, CMinked coniferyl and sinapyl aldehydes in lignifying cell walls are the main targets of the Wiesner (phloroglucinol-HCl) reaction, Protoplasma 220 17-28. 

By contrast, the 3D structural analysis of a bona fide CAD has been reported only for the Arabidopsis AtCAD4 and AtCAD5, as two other reports of putative CADs from Saccharomyces cerevisiae and Populus tremuloides (aspen) are not currently considered as CADs proper. Saccharomyces cerevisiae does not produce metabolites in the phenylpropanoid pathway, thereby making it unclear as to why this specific metabolic role was being contemplated. In addition, the putative sinapyl aldehyde dehydrogenase (SAD) from aspen was not established to have the specific function claimed (see Davin etal and Anterola and Lewis " for a full discussion). 

Other cinnamic acids also produce aldehydes, but they have no significance as odour-active substances. By analogy, coumaralde-hyde is produced from 4-coumaric acid, caffeoyl aldehyde from caffeic acid, conifer aldehyde (also known as ferulyl aldehyde) from ferulic acid, 5-hydroxyconifer aldehyde from 5-hydroxyferulic acid and sinapyl aldehyde from sinapic acid. These aldehydes can be reduced to the corresponding alcohols, with which they play a role as the building units of lignin biosynthesis. 

Lignin has a complex structure that varies with the source, growing conditions, etc. This complex and varied structure is typical of many plant-derived macromolecules. Lignin is generally considered as being formed from three different phenylpropanoid alcohols— coniferyl, coumaryl, and sinapyl alcohols, which are synthesized from phenylalanine via various cinnamic acid derivatives and commercially is sometimes treated as being composed of a Cg repeat unit where the superstructure contains aromatic and aliphatic alcohols and ethers, and aliphatic aldehydes and vinyl units. 

The key intermediate for this synthesis was an aromatic aldehyde, linked with sinapyl alcohol (156) through a dioxane bridge. The aldehyde 166, on treatment with the appropriate phosphonium salt, yielded the desired stilbene. The essential steps of the preparation of the intermediate are summarized below. 

Cycloaddition of orf/io-quinone 162 with ferf-butyldimethylsilyl ether of sinapyl alcohol (163) yielded the 1,4-dioxane-linked adduct 164, as shown in Scheme 10b, but no regioisomer was detected. The ketal group in 164 was removed under acidic conditions and the derived ketone, a trans-cis mixmre in the ratio of 2 1, on treatment with alkali, yielded the frans-isomer, 165, in a good yield. The ketone 165 was converted to the key intermediate aldehyde 166 through the iodoform reaction, esterification, LAH reduction, and oxidation with Dess-Martin periodinane after protection of the hydroxy groups by MOM groups (Scheme 10b). 

The main monolignols are coniferyl, sinapyl, and p-coumaryl alcohols. Cinnamic aldehydes and acids that are biogenetic precursors to the monolignol can also take part in the biosynthesis. This chapter is concerned with the topological aspects of the structnral organisation of lignin. 

Lignin accounts for about 17%-28% of dry weight of grapevines (20% on average in vine shoots [119]). It possesses a three-dimensional amorphous structure resulting from the polymerization of coniferyl, sinapyl, and p-coumaryl alcohol units (Figure 4.9), that is typical of hardwood [120], and its degradation produces low-molecular mass phenolic alcohols, aldehydes, ketones, and acids [121,122], as well... 

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