Amino methyl imidazoles of Formula I are provided: ##STR00001## wherein R, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 are defined herein.Such compounds are ligands of C5a receptors. Preferred compounds of Formula I bind to C5a receptors with high affinity and exhibit neutral antagonist or inverse agonist activity at C5a receptors. This invention also relates to pharmaceutical compositions comprising such compounds. It further relates to the use of such compounds in treating a variety of inflammatory, cardiovascular, and immune system disorders. Additionally, this invention provides labeled amino methyl imidazoles compounds, which are useful as probes for the localization of C5a receptors.