Receptors, once considered a class of opioid receptors, are now regarded as a unique class of receptors that contain binding sites for a wide range of ligands, including the drug 1-N(2 ,6 -dimethylmorpholino)3-(4-t-butylpropylamine) (fenpropimorph), a yeast sterol isomerase inhibitor. Because fenpropimorph has high-binding affinity to the -1 receptor, we have synthesized a series of fenpropimor...