The Acridines

The Acridines. Their Preparation, Physical, Chemical, and Biological Properties and Uses. By Adrien Albert, D.Sc., Ph.D., B.Sc., F.R. l.C. (Pp. 381. £3 lOs.) London: Edward Arnold. 1951. Professor Albert has collected the many important original contributions made by himself and his coworkers on the synthesis, physical chemistry, and antiseptic properties of aminoacridine compounds, and the relations between physicochemical characters and antibacterial action. In addition, he has produced a monograph dealing with practically everything that is known of the chemistry, biological properties, and medical applicationis of members of the acridine series. The work is divided into four parts, concerned respectively with preparative methods, physical and chemical properties, biological properties and uses, and other uses, this last including such varied topics as the use of acridines in dyeing, relations between colour and chemical constitution, the use of acridines in analytical work, their fluorescence, and, in certain instances, chemiluminescence. An appendix is devoted to the manipulation and purification of acridine compounds. The first attempts at medical applications were those of Auclert (1888), who found that chrysaniline had a certain, although unreliable, analgesic effect and when taken internially was mydriatic, and of Mannaberg, who tested chrysaniline derivatives for antimalarial action but found this unreliable. Ehrlich, in connexion with his studies on chemotherapy of trypanosomiasis, commissioned Benda to prepare trypaflavin, a quaternary diamino-acridine derivative, which proved to be highly effective against T. brucei in mice. Then Browning and Gilmour showed that this compound, later known as acriflavine, and its precursor, proflavine, were powerfully inhibitory toward both Gram-positive and Gramnegative bacteria in a medium such as peptone water, and also that, contrary to most of the powerful antiseptics then known, they were not reduced in their antiseptic potency by the presence of blood serum. In the war of 1914-18, when sepsis was so serious a problem, these substances were widely used in wound dressings. They proved to be powerful in combating local infections and relatively innocuous to the tissues, although prolonged application interfered with healing. Albert introduced "aminacrine " (5-aminoacridine), w&hich has all the desirable properties of the class and is practically colourless. He showed that the antibacterial action of members of the group is highly correlated with their basicity, and has also emphasized that solutions of salts applied to the tissues should not have an acid pH. The aminoacridines have enjoyed a long term of clinical use as antibacterials, and it is noted that in 1946-7 the annual production was 20 tons in England and 14tons in Australia. It is of interest, too, that mepacrine, the valuable quinine substitute, is an acridine derivative. The chemical sections are on the preparation and properties of acridines, acridans, acridones, and their derivatives. The preparative section is notable for clarity and detail of statement and for frequent critical appraisal of the procedures described. This book is stated to be the first devoted solely to the acridines; it is well documented, and an excellent authorreference index is supplied. References are run in the text and are also set in many of the 99 tables in which textual matter is summarized and extended. The exposition is most stimulating, and those interested in any aspect of the subject will find a rich store of information.