298 SCIENCE PROGRESS 



hydroxyl group, this body must be regarded as a tri-sub- 

 stituted phenanthrene of the formula : 



(CH 3 0),C, 4 H 7 OH 



When oxidised with a mixture of glacial acetic acid and 

 chromic acid, acetylthebaol is converted into a compound 

 which possesses the formula C 18 H 14 6 and exhibits all the 

 properties of a quinone. This body has been designated 

 acetylthebaolquinone and yields thebaolquinone on saponifica- 

 tion (cf. p. 285) : 



CH 3 0\ CH 3 0\ 



>(C„H 7 )0 . OC . CH 3 -> >(C, 4 H 5 2 )0 . OC . CH S -> 



CH.O/ CH 3 0/ 



Acetylthebaol Acetylthebaolquinone 



CH 3 0\ 

 -> XC M H 6 0,).OH 



CH 3 0/ 



Thebaolquinone 



Thebaolquinone exhibits the characteristic reaction of an 

 ortho-diketone in that it combines with ortho-diamines, in 

 view ol which fact, as also on account of its other properties, 

 it must be a tri-substituted phenanthraquinone. None of the 

 substituting radicles in thebaol can therefore be attached to the 

 " bridge " atoms of the phenanthrene complex, for any groups 

 so attached would necessarily have disappeared in the process 

 ol oxidation. An insight into the position of the methoxyl 

 groups in thebaolquinone is given by the oxidation of that 

 body with permanganate. Under this treatment an acid of 

 the formula C 9 H 8 5 and identical with o-methoxyphthalic 

 acid has been obtained, from which it follows that the two 

 methoxyl groups in thebaolquinone cannot both be bound to the 

 same ring. 



Pschorr, Seydel, and Stohrer 1 have recently synthesised 

 thebaol and have proved that that body is a 3, 6-dimethoxy- 

 4-hydroxyphenanthrene of the formula : 



CH a O 



HO 



CHsO 



1 Ber. 35, 4400. 



