Phytotropins: Conformational requirements for the abolition of the root geotropic response

Abstract

Compounds of the phytotropin class have been assessed for possible conformational requirements with respect to their ability to aftect the root geotropic response. It is shown that part of the molecule may need to adopt a planar configuration, and evidence is adduced which indicates that the remainder of the molecule may also have conformational requirements which need further definition. It is suggested that molecules which favour a conformation such that the aromatic ring which bears the carboxyl function is out of plane with the remainder of the molecule may have activity. Coplanarity of the carboxyl group with the ring to which it is attached is not a prerequisite for activity.