Preparation, crystal and molecular structure, and evaluation of plant growth regulating activity of guanidinoalkanephosphinates and phosphonates

A series of previously unknown α-guanidinoalkanephosphonous, α- and β-guanidinoalkanephosphonic acids has been prepared in order to study their structures and biological activity. Aminoalkanephosphonous and phosphonic acids have been converted into their guanidino derivatives by means of S-methylisothiourea hydroiodide or cyanamide amidination. The crystal and molecular structures of three guanidino acids have been determined by single-crystal X-ray diffraction. The plant growth regulating activity of all synthesized guanidinoalkanephosphinates and phosphonates has been evaluated on Lepidium sativum. © 1995 John Wiley & Sons, Inc.