52 SECTIONAL ADDRESSES 
and an example of the methods adopted may be schematically indicated 
in the case of malvin. 
MeO MeO 
Acog’ coc! CHAN: Aco co-cHN,  HCO.H 
MeO MeO 
MeO FtOH MeO 
AcO CO: CHEO-CHO Mn... es Aco¢ CO-CH,OH 
MeO MeO 
Hy 
Bromoacetoglucose, 
Ag,CO, 
Bromoacetoglucose 
HO /\.0H 
OM 
CHO KOH in MeCN wae 
for 
HO 
HO/\OH A | 
HCl in CH, 
CHO EtAc mis 
(AcO),:C,H,O-O O-C,H,O(OAc),4 
.-_s. —__~ 
rg Cl 
pee 
IE O OMe 
. va HO 1s < oH 
acetylated hydrolysis Ba(OH), | OMe 
malvin SE EnEEEEEEEEEEEEEEEEE O-C,H,,0;° 
chloride HsO, tcl  C,8:{0;-0 
(XXV) 
The anthocyanins can be characterised and qualitatively distinguished 
by their distribution between immiscible solvents, and in the case of 
disaccharides the use of n-butyl alcohol is convenient (demonstration). 
Acylated anthocyanins occur in all the anthocyanidin series ; thus, on 
hydrolysis, delphinin, the pigment of species of delphinium, furnishes 
p-hydroxybenzoic acid as well as glucose and delphinidin. 
Many other delphinidin derivatives are acylated by means of p-hydroxy- 
cinnamic acid, probably attached to the sugar hydroxyls, and pelargonin 
and cyanin also occur in acylated forms. ‘These so-called complex antho- 
cyanins are characterised by high distribution numbers ; they are usually 
acylated 3 : 5-dimonosides, but in the delphinidin series, gentianin and 
violanin appear to be p-hydroxycinnamates of delphinidin monoglucoside 
and rhamnoglucoside respectively (Karrer). There is also some evidence 
of another type of depside anthocyanin in which the acyl group is directly 
attached to the anthocyanidin molecule and the glucoside group is borne 
by the hydroxyl of the acid residue. 
e 
OAc 
CO OMe 
