Chemical structure and biological activity 



Table 4 



The Xu values of the most active growth promoters between the A^ values 

 of the most active growth inhibitors 



Growth substances 



Indole-3-acetonitrile 



CHjCN 



Indole-3-acetic 

 acid 



CHjCOOH 



2:'»-Dichlorophen- 

 oxyacetic acid 



CI 



2:t:5-Trichlorophen- 

 oxyacetic acid 



CI ■ 



Cl< >0CH2C00H 



CI 



oi-Naphthylacetic 

 acid 



CHjCOOH 



2:3:6-Trichlorobenzoic 

 acid 



CI 



OCH2COOH 



CI 



a a 



COOH 



Figure 8. Molecular models of six of the most important growth-promoting substances. 



150 



