Conformational behaviour of some tachykinin C-terminal heptapeptides.

The conformational behaviour of substance P, physalaemin and eledoisin C-terminal heptapeptides was investigated using empirical energy calculations. Although the conformational distributions of the three heptapeptides are somewhat different, they have a few common low energy conformations. Some of them, which satisfy the structure-activity relationships, may fit the well known SP-P receptors.