THE ALUMNI JOURNAL. 



35 



RELATIONSHIP BETWEEN THE CHEMICAL CONSTITUTION AND THE PHYSI= 

 OLOQICAL ACTION OF THE NEWER SYNTHETIC REHEDIES. 



Delivered at the meeting of the Alumni Association, January loth, 1894. 



By VIRGIL COBLENTZ, A.M., Ph.G., Ph.D. 



Professor of Theory and Practice of Pharmacy, Director of the Pharmaceutical Laboratory. 



{Contimied from page jo.) 



T^HE question of relationship between 

 ^ physiological action and chemical 

 constitution has often been considered, 

 but never has it received the careful and 

 systematic study, that has of late years 

 been bestowed upon it. This has been 

 brought about by the vast number of 

 organic syntheses, for among these pro- 

 ducts, many valuable medicinal remedies 

 have been discovered. From the time of 

 its discovery in 1820, quinine has held 

 the field as an antipyretic ' ' par excel 

 lence. ' ' The labors of Koenigs, Skraup, 

 Hesse and others, have lent much to the 

 explanation of its constitution. Its oxy- 

 dation by means of CrOj have shown it to 

 be a derivative of chinolin, inasmuch as it 

 yielded ox3^-methyl-chinolin-carboxylic- 



00 FT 

 acid C9H5N<^j-.^^|t On heating with 



alkalies they obtained chinolin and deriv- 

 atives of same. By action of HNO;,, the 

 chinolin molecule was more thoroughly 

 split up, yielding pyridin-carboxylic 

 acids. With this relationship between 

 quinine and chinolin established, the 

 medicinal properties of the latter mother 

 substance were studied. Donat first 

 pointed out its antiseptic properties, later 

 such salts as the tartrate and salicjdate 

 found application as febrifuges. In 1882 

 under the name of " Kairin," O. Fischer 

 introduced the first synthetic substitute 

 for quinine, consisting of the following 

 chinolin derivatives ; the hydrochloride 

 of oxy - chinolin - methyl - tetra - hj^drur 

 (Kairin- M) and the hydrochloride of oxy- 

 chinolin-ethyl-tertahydrur (Kairin- A). 



This opened a new era in synthetic 

 antipyretics. Two j^ears later Knorr 

 followed with his discovery of antipyrin, 

 obtained by methylating the condensa- 

 tions product of phenyl-hydrazin with 

 aceto-acetic-ether. This was quickly fol- 

 lowed by Skraups Thallin a tetra-hydro- 

 p-chin-anisol. A close examination of 

 these antipyretics will show that they all 

 contain a N united under similar condi- 

 tions, this plays a most important part, in 

 consequence of its affinity for other 

 elements, and lends a basic character to 

 the bodies in question. Such syntheses 

 are of equal value to both the chemist 

 and physician, the}- demonstrate to the 

 chemist that the sj^stematic analysis 

 yields valuable conclusions, which furnish 

 the key to an unlimited variet}^ of possi- 

 bilities, while it assures the physician of 

 a still further improvement of the thera- 

 peutic value of already valuable remedies. 

 Since these discoveries, it has been the 

 earnest labor of pharmacologists to trace, 

 if possible, a definite relationship that 

 might exist between certain chemical 

 groups or groupings of different bodies, 

 and their physiological action ; their 

 efforts have been rewarded bj^ some 

 valuable discoveries, although as yet, 

 comparative little progress has been 

 made, it does not shut out future possi- 

 bilities. The time will come when our 

 knowledge concerning this subject, will 

 be so advanced that the chemist will be 

 able to construct compounds to meet the 

 most exacting requirements of modern 

 medicine. 



