THE FLAVONES OF RHUS 
dissolved in a small volume of hot alcohol, filtered, and fractionally 
precipitated with water. The fractions were separately dried and 
acetylated by heating for an hour with anhydrous sodium acetate and 
acetic anhydride. The reaction mixture was poured into water and 
after twenty-four hours the precipitated acetyl fisetin was filtered 
off and purified by recrystallization from alcohol. The acetyl deriva- 
tive formed a mat of silk-like colorless needles, insoluble in water, 
insoluble in cold, and sparingly soluble in hot alcohol, and easily 
soluble in warm glacial acetic acid. Since the several fractions had 
the same melting point, 199-200.5° C. (uncorrected), they were com- 
bined and again purified by recrystallization. The purified acetyl 
fisetin, derived from R. typhina, gave a yield of 61.66 percent of 
fisetin by hydrolysis, agreeing satisfactorily with the theoretical yield 
of 62.99 percent from Ci5H606(C2H30)4. Had the formula of the 
acetyl compound been Ci5H506(C2H30)5 theory would have required 
57.66 percent flavone; if Ci5H706(C2H30)3, 69.41 percent. The 
hydrolysis was carried out in acetic acid solution, with sulphuric 
acid. The recovered flavone was precipitated by the addition of 
water. The acetyl fisetin derived from both species had the same 
melting point, and since combustions of the recovered flavone were 
made for both, it was deemed sufficient to make combustions of the 
acetyl fisetin from one source only.* The results are given in Table I. 
Table I 
Combustions of Acetyl Derivative of Fisetin from Wood of Rhus typhina 
Sample 
Arithmetic mean of three determination; 
Weighted mean 
Required for Ci5H606(C2H30)4 
Weight 
CO2 
H2O 
c, % 
H, % 
0, % 
.1225 
.1054 
.2046 
.2724 
.2372 
.4600 
.0418 
.0382 
.0724 
60.64 
61.37 
61.31 
61.10 
3.82 
4.06 
3-96 
3-94 
3-95 
3-96 
35-54 
34-57 
34-73 
34- 96 
34.91 
35- 25 
61.14 
60.79 
The pure fisetin was of a pale lemon yellow color, insoluble in cold 
water, very sparingly soluble in hot water, readily in alcohol and ace- 
tone. It was removed from aqueous or very dilute alcoholic solutions 
by acetic ether or ether, but after drying dissolved in ether only with 
difficulty. It was insoluble in benzene and chloroform. With ferric 
chloride it gave an olive-green coloration, with lead acetate an orange- 
red precipitate, with ammonia and other alkalies an intensification of 
