254 H. G. SMITH AND J. READ. 
In its general physical and chemical behaviour, this 
secretion of Alphitonia excelsa shows.a marked resemblance. 
to fustin, a glucoside of fisetin, melting at 218 — 219°, which 
was first isolated from the wood of young fustic, Rhus 
cotinus, L., by Schmid (Ber., 1886, 19, 1734). Fisetin itself, 
the yellow colouring matter of young fustic, had been 
extracted and characterised many years previously by 
Chevreul, who called it “fustin’’ (Legons de Chimie appli- 
quées a la teinture, A. II, p. 150). Later, fisetin was 
shown by A. G, Perkin (Trans. Chem. Soc., 1897, 71, 1194) 
to occur in the wood of Rhodosphacra rodanthema, Engl. 
—the yellow cedar of New South Wales—both in the free 
State and in the form of a supposed glucoside, melting at 
215—217°, and corresponding to the formula CsgHs0Q01.. 
Owing to its unusual resistance to hydrolysis, the complete 
diagnosis of this substance has been attended with consider- 
able difficulty, and some doubt still exists concerning the 
identity of the substance from Rhodosphacra rodanthema, ° 
melting at 215—217°, with the fustin from Rhus cotinus, 
melting at 218—219°. Perkin (loc. cit., p. 1197) originally 
considered the substances to be probably distinct, but more 
recently mention has been made of the possibility of their 
identity (Perkin and Everest, The Natural Organic Colour- 
ing Matters, 1918, p. 186). 
It was surmised by Schmid that fustin yielded rhamnose 
on hydrolysis, and Perkin accordingly suggested the formula 
CssH26O14 for this substance, the hydrolysis being thus 
represented by the following equation :— 
OseH26O14 + 4H2ZO = 2 OisHi0O6 + CeHi40c. 
This formula requires C = 63°34, and H = 3°81 per cent., 
whilst Schmid obtained OC = 62°70; 62°77, and H = 4°35; 
4°54 per cent. Perkin’s values, O =60°21, and H = 4°00 
per cent., correspond more closely with OseH30O016. The 
hydrolysis would then be represented as below:— 
Cse6Ha0O1g + 2H,O = 2 O15Hi0Og + OgHis0c. 
