Ryan and Walsh — Studies in the Diflavone Group. 195 



group which contain two ehromophore radicals symmetrically placed in the 

 molecule : — 



,N : N . Y 

 X 

 \N : N . Y 



it has been concluded by von Kostanecki, Lampe, and Milobedzcka [Ber. 43 

 (1910), p. 2163], that curcumin also contains two ehromophores symmetrically 



placed in the molecule : — 



,CO . CH : CH . Y 

 X 

 N)0 . CH : CH . Y 



Curcumin, inasmuch as it is a j3-diketone, is also a mordant dye (Werner. 

 Ber. 41 (1908), p. 1057). 



It is generally held (c.f. von Kostanecki, Lampe, and Milobedzcka 

 (loc. cit.)) that the auxochromic character of the hydroxyl radical in the 

 " vanillin rest " is not very marked, and if this is true, the dimethylether of 

 curcumin should not, as a dye, differ very markedly from curcumin, nor should 

 the tinctorial character of diveratrylidene-diacetoresorcinol differ very much 

 from that of curcumin, if the former substance is a mordant dye. 



Experiments showed, however, that diveratrylidene-diacetoresorcinol is 

 not a direct dye, and its tinctorial effects on samples of wool mordanted with 

 alumina, tin salt, iron salt, and chrome salt respectively are so slightly 

 marked that the substance can scarcely be regarded as a mordant dye. 



Experimental. 



Diacetoresorcinol, which was obtained by the action of zinc chloride on 

 resorcinol-diacetate, was converted by means of dimethyl sulphate and 

 potash into diacetoresorcinol-dimethyleter, following the method already 

 described by Kyan and O'Neill (Proc. Royal Irish Acad., 1915, B, p. 48). It 

 condensed readily with veratric aldehyde in the presence of alcoholic sodium 

 hydroxide to form diveratrylidene-diacetoresorcinol-dimethylether. 



(1) Diveratrylidene-Diacetoresorcinol-Dimethylether. 



OCH 3 OCH 3 



CH 3 0/\ CH 3 0/\OCH 3 /\OCH 3 



\/CH : CH . CO\/CO . CH : CH\/ 



1 c.c. of 50 per cent, sodium hydrate was added to a hot solution of 

 2 grams of diacetoresorcinol dimethylether and 2 grams of veratric aldehyde 

 in 20 c.cs. of alcohol. On warming the mixture for a short time on the 



