966) and NK-κB (docking score = −9.274) compared to acetylsalicylic acid 3 (docking score for COX-2 = −5.412; for NK-κB = −5.525) [13]. Furthermore, salicylates Cyclopamine nmr exhibit other biological activities, including anticancer and anti-proliferation [12]. The significance of β-d-salicin 1 molecule may encourage further understanding into its cross-biological function. Therefore, the aim of this article is to explore the mechanistic biosynthetic pathways of β-d-salicin 1, its metabolism and discuss the genetic cross-talk between pants and humans. β-d-Salicin 1 or
2-(hydroxymethyl) phenyl-O-β-d-glucopyranoside is the first phenolic glycoside discovered in nature with a molecular mass of 286.27782 g/mol. Its IUPAC name is (2R,3S,4S,5R,6S)-2-(hydroxymethyl)-6-[2-(hydroxymethyl) phenoxy]oxane-3,4,5-triol. β-d-Glucose 4 moiety of β-d-salicin 1
contributes to all five chiral carbon centres. The chemical structure of β-d-salicin 1 encompasses β-d-glucose 4 and 2-hydroxybenzyl alcohol, or salicyl alcohol 5. β-d-Salicin 1 contains seven oxygen atoms, as H-bond acceptor and five hydroxyl groups, as H-bond donors. It 1 also possesses nine rotational selleck chemical bonds that control its conformational structure. In addition, the β-d-glucose 4 and salicyl alcohol 5 moieties are bonded by β-1,1′-d-glycosidic bond. These chemical features contribute to the polarity of β-d-salicin 1. Therefore, the extraction of β-d-salicin 1 requires a polar solvent system, such as boiling water and ethyl alcohol. In addition, the presence of d-glucose 4 moiety contributes to the enhancement of physcochemical properties of β-d-salicin 1. Although there have been long-standing biotic and abiotic interests in β-d-salicin 1, no defined biosynthetic pathway, genes or enzymes have been illustrated in the literature [14] and [15]. Nonetheless, adapting the biotechnological approach and utilising leave tissues and radio labelled precursors have elucidated some biosynthetic
aspects of β-d-salicin 1 in Salix and Populous [16] and [17]. It reveals that the biosynthesis of β-d-salicin 1 is associated with phenylpropanoid pathway that starts with l-phenylalanine 6 ( Scheme 1). Using radiolabled precursors indicate that the biosynthesis of β-d-salicin 1 encompasses five steps: deamination, ortho-hydroxylation, VAV2 β-oxidation, C2 unite elimination and glucosylation [7] and [16]. l-Phenylalanine 6 is available in plants and readily biotransforms into trans cinnamic acid 7 by phenylalanine ammonialyase (PAL) [18]. Thereby, plants produce a large number of organic compounds via this biotransformation [19]. The catalysis of l-phenylalanine 6 involves deamination of the amino group of α-amino acid. The mechanism of this biotransformation involves the formation of an enzyme-substrate complex, generating a carbonium ion intermediate which subsequently induces the elimination of the 3-pro-S proton giving trans-cinnamic acid 7 in a stereospecific manner ( Scheme 2).