The syntheses of seven novel synthetic analogues of the naturally occurring insecticide ryanodine are described. These, and other synthetic and naturally occurring analogues, have been used to characterise the selectivity of a monoclonal antibody which has been produced by immunisation with 9hydroxy-21-(4-azidobenzyloxy)-9-epiryanodine photo-conjugated to keyhole limpet haemocyanin. The antibody binds [3H]ryanodine with a dissociation constant of 0É37 nM. The speciÐcity of this antibody in terms of its ability to recognise 11 natural and synthetic analogues of ryanodine has been determined by [3H]ryanodine displacement and shown to be similar (for a partially overlapping set of analogues) to that determined earlier for a rabbit polyclonal antibody (Kahl, S. D., et al., Anal. Biochem., 218 (1994) 55È62). The selectivity of the antibodies is shown to be related to that of the sarcoplasmic reticulum Ca2r elease channel from rabbit skeletal muscle, both for this set of ryanodine analogues and for three structurally dissimilar, low-molecular-weight compounds identiÐed by high-throughput screening. The advantages of these antibody models of the Ca2`release channel for screening are illustrated by their superior performance in a homogeneous binding assay.
1998 Society of Chemical ( Industry