Bradycardic effects of clonidine

Alkylation of clonidine (133) with allyl bromide gave alinidine (138) [167] and with 2-chlorotetrahydropyran piclonidine (139) [168]. Preliminary clinical trials of alinidine demonstrated a bradycardic effect mediated through direct action on the atrial sinus [167], The slow and economic heart rate was thought to be desirable in the management of coronary heart disease [169]. Piclonidine is less potent than clonidine, but it does not evoke hypertensive episodes or cause sedation [168,170,171]. 

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