RING SUBSTITUTIONAL REQUIREMENT FOR BIOLOGICAL ACTIVITY OF 5-ARYL-3-ALKOXY-(2E,4E)-2,4-PENTADIENOIC ACIDS AS NEW GROWTH REGULATORS. THEORETICAL TREATMENT

A new hypothesis of plant hormones is proposed to predict, in a simple way, the strength of activity of 5- aryl-3-alkoxy-(2e,4e)-2,4-pentadienoic acids as new plant growth regulators from the value of total dipole moment (tdm) in the molecule under investigation using am1 semi-empirical quantum mechanical methods. the validity of this hypothesis is checked by comparisons with experimental results obtained by other investigations. good agreement between experimental and calculated values is observed.