Chemical Diversity of Plant Cyanogenic Glycosides: An Overview of Reported Natural Products.

Christian Zidorn,Meri Yulvianti

doi:10.3390/molecules26030719

Christian Zidorn, Meri Yulvianti

Open Access

https://doi.org/10.3390/molecules26030719

Copy DOI

Abstract

Cyanogenic glycosides are an important and widespread class of plant natural products, which are however structurally less diverse than many other classes of natural products. So far, 112 naturally occurring cyanogenic glycosides have been described in the phytochemical literature. Currently, these unique compounds have been reported from more than 2500 plant species. Natural cyanogenic glycosides show variations regarding both the aglycone and the sugar part of the molecules. The predominant sugar moiety is glucose but many substitution patterns of this glucose moiety exist in nature. Regarding the aglycone moiety, four different basic classes can be distinguished, aliphatic, cyclic, aromatic, and heterocyclic aglycones. Our overview covers all cyanogenic glycosides isolated from plants and includes 33 compounds with a non-cyclic aglycone, 20 cyclopentane derivatives, 55 natural products with an aromatic aglycone, and four dihydropyridone derivatives. In the following sections, we will provide an overview about the chemical diversity known so far and mention the first source from which the respective compounds had been isolated. This review will serve as a first reference for researchers trying to find new cyanogenic glycosides and highlights some gaps in the knowledge about the exact structures of already described compounds.

Highlights

Received: 1 January 2021Like many other plant natural products, cyanogenic glycosides serve as defense agents against herbivores, in this case by releasing toxic hydrogen cyanide after tissue damage.Some plant species are deadly for humans due to their high content of cyanogenic glycosides
To the best of our knowledge, the latest addition to the list of naturally occurring cyanogenic glycosides is prunasin methacrylate (71), which was isolated from Centaurea microcarpa Coss. & Durieu ex Batt. & Trab. (Asteraceae) in 2018 [3]
The keyword “cyanogenic glycosides” was used to search the literature for references to this particular group of compounds; in this way, we found numerous articles, book chapters, and seminar proceedings, some dating back to the 19th century

Summary

Introduction

Some plant species are deadly for humans due to their high content of cyanogenic glycosides. For other species, used as staple foods, the content of cyanogenic glycosides requires special modes of preparation in order to detoxify the plants before human consumption. For a third group of plants, the moderate content (or the additional/consumption in moderate amounts) of cyanogenic glycoside makes them highly praised aroma plants (such as almonds in the production of marzipan). The first cyanogenic glycoside that was isolated from a plant source was amygdalin (65) which was obtained from bitter almonds [Prunus dulcis (Mill.) D.Webb var. To the best of our knowledge, the latest addition to the list of naturally occurring cyanogenic glycosides is prunasin methacrylate (71), which was isolated from Centaurea microcarpa Coss. To the best of our knowledge, the latest addition to the list of naturally occurring cyanogenic glycosides is prunasin methacrylate (71), which was isolated from Centaurea microcarpa Coss. & Durieu ex Batt. & Trab. (Asteraceae) in 2018 [3]

Methods

Results

Conclusion