^^oL. 12 (i953) biochimica et biophysica acta 75 



THE REACTION OF THE CARCINOGENIC DIBENZCARBAZOLES AND 

 DIBENZACRIDINES WITH PURINES AND NUCLEIC ACID 



by 



J. BOOTH AND E. BOYLAND 

 The Chester Beatty Research Institute, Royal Cancer Hospital, London, S.PF.3 {England) 



Polycyclic compounds without polar groups are only slightly soluble in water and 

 the solubilities usually decrease with increase in molecular size. The solubility of such 

 substances is however much greater in the presence of caffeine (Brock, Druckrey and 

 Hamperl^). Weil-Malherbe- measured the solubility of a number of hydrocarbons in 

 many different purine solutions and found that the efficiency of purines as solubilising 

 agents increased with increasing oxidation and N-methylation, 1:3:7: g-tetramethyluric 

 acid being the most efficient purine examined. 



H . 



J 



54 654 



Carbazole Acridine 



CHo CHo 



O I ' O I ' 



I II } I II >=o 



O^^N^'^N'^ 0*='"^N^'^N 



I I I 



CHj Crij CHg 



Caffeine 1:3:7: 9-Tetramethyluric acid 



The increased solubilities may be due to the formation of molecular compounds or 

 complexes, and well-defined crystalline compounds containing one molecule of pyrene 

 and one molecule of tetramethyluric acid, and containing one molecule of 3:4-benz- 

 pyrene and two molecules of tetramethyluric acid were prepared by Weil-Malherbe^. 



The solubilities of carcinogenic aromatic amines such as 2-naphthylamine, 2- 

 aminofluorene, 2-anthramine, 4-aminostilbene, 4-aminoazobenzene and benzidme in 

 water are also greatly increased by the addition of caffeine or tetramethyluric acid 

 (Neish^). 



This work has been extended to the dibenzocarbazoles which had been shown to be 

 carcinogenic by Boyland and Brues^, 1:2-6:7- and 3 : 4-6 : 7-dibenzacridines which are 

 known to be carcinogenic (Barry, Cook, Haslewood, Hewett, Hieger and Kenna- 

 way^) and i : 2-8 : 9-dibenzacridine which is being tested by Lacassagne (personal 

 communication) . 



References p. 8y. 



