Phyto-pharmacological Study of Isomers 35 



11 (1971) 



A phyto-pharmacological study of some isomers. 

 By DAVID I. MACHT 



[From the Pharmacological Laboratory, Johns Hopkins Uni- 

 versity, Baltimore, Md.] 



A phyto-pharmacological study was carried out much in the 

 same way as the effects of cocaine were studied by Macht and 

 Livingston. The influence of a number of isomeric drugs was 

 studied on the roots of lupinus albus. The following structural 

 chemical isomers were examined : normal propyl alcohol and 

 isopropyl alcohol, primary butyl alcohol and secondary butyl 

 alcohol; primary amyl alcohol and secondary amyl alcohol. It 

 was found in every case that the normal or primary alcohols were 

 more toxic to the growth of the lupine than the corresponding 

 secondary alcohols. 



The following stereo-isomers were examined : laevogyrous 

 camphor, dextrogyrous camphor and optically inactive camphor ; 

 quinin and quinidin; cinchonin and cinchonidin. It was found 

 that laevogyrous camphor was more toxic than the dextro variety, 

 while the inactive camphor produced an effect equivalent to the 

 mean of the other two. Quinin (sulphate) which is laevogyrous 

 was found to be more toxic than quinidin (sulphate) which is its 

 dextrogyrous isomer. In the same way cinchonidin (sulphate) 

 which is laevogyrous was more toxic than cinchonin (sulphate) 

 which is its dextrogyrous isomer. 



The difference in toxicity between the various forms of cam- 

 phor is also illustrated by the effect of solutions of these drugs 

 on the growth of moulds and bacteria. Aqueous solutions of the 

 three varieties of camphor were made and exposed to the air. It 

 was found that the dextro-camphor solution very soon became 

 cloudy. The solution of inactive camphor became contaminated 

 with bacteria and moulds some time later, while the solution of 

 laevogyrous camphor remained clear for a very long time. The 

 relative toxicity of both the primary and secondary alcohols and 

 the various stereo-isomers which were studied corresponds to 

 the relative toxicity of the same drugs for animals tissues as 

 studied by the author. 



