TRANSACTIONS OF SECTION B. 



619 



II. Di-Naphthacridines, 

 The following formulsB represent all the possible di-naphthacridines :- 



/3N/3 



a C a 

 (Reed) 



iSNa 



oC 3 

 (Ullmann) 



;3Cj8 

 (Senier and Goodwin) 



(Unknown) 



I 



Co 



(Strohbach) 



The notation adopted is, I think, more convenient than either that of Graebe, 

 adopted by Ullmann, or that of Strohbach, adopted by Mohlau. The numbering 

 is taken from Mohlau and Haase. 



The naphthacridines are obtained by methods analogous to the acridines, 

 including especially the aldehyde and the methylenediiodide reactions with 

 naphthylamines. The naphthacridine of Reed and that just announced by 

 Ullmann, both obtained originally by the use of formaldehyde, I have prepared 

 by the methylenediiodide method. There is every reason to hope that the two 

 unknown types of this group of acridines or derivatives of them will soon be 

 discovered. 



