Design, synthesis and biological activity of some tetraamines related to methoctramine and 4-DAMP

Three novel tetraamines (1–3) related to methoctramine were designed, and their biological profiles at muscarinic receptor subtypes were assessed by binding assays. It turned out that the constrained analogue spirotramine (3, FC 15–94) of 4-DAMP has an affinity profile better than that of pirenzepine owing to a high affinity for muscarinic M1 receptors and a significantly lower affinity for the M2, M3 and M4 subtypes.