1 84 BIOCHEMICAL SYSTEMATICS 



(7) Gynocardoside (the structure has not been completely 

 established, in particular the positioning of three OH 

 groups attached to the aglycone) is from Gynocardium 

 and Pangium (family Flacourtiaceae). 



CH2OH 



C< {C5H5(OH)3 



OH 

 Positions of (OH) groups are doubtful. 



In the second series, the nitrile group is attached to the glycosidic 

 group. 



(8) Lotusoside (lotusin) is from Lotus arabicus. 



C11H21O10 — CH — O 



C=N 



HO 







Although the formula above had been accepted for many 

 years, work by Doporto et al. (1955) has established rather conclu- 

 sively that the "flavone" portion is incorrectly identified. These 

 investigators obtained some of the original samples and identified 

 the components as a mixture of quercetin and kaempferol (flavonols). 



The authors did not discuss lotusin itself, only the flavonol 

 degradation products. If both these flavonols are derived from lotusin 

 itself, then there must be two different lotusins present. Apparently 

 more work is needed on the intact cyanogen. 



The list of cyanogenetic compounds above agrees essentially 

 with that of Gibbs (1954) except for two compounds, hiptagin and 

 karakin, which Dillemann described as "pseudo-cyanogenetic" 

 heterosides, and a third, macrozamoside, derived from several 

 cycads including Macrozamia spiralis. Another substance, cycasin 

 found in Cycas revoluta, consists of the same parent substance as 

 macrozamin but is esterified with glucose (Nishidi et al., 1960). These 

 substances do not liberate HON in hydrolysis with dilute HCl unless 

 first treated with sodium hydroxide solution, then acidified. They are 

 called pseudo-cyanogenetic substances by Lythgoe and Riggs (1949). 

 According to these authors (see also Langley et al., 1951, who were 

 studying macrozamin, the substance responsible for the condition 

 known as "wobbles" or "staggers" in Australian livestock) it is a 



