X-ray structure determination of tryptamine hydrochloride

Molecular characteristics of biogenic monoamines and their analogs

Until recently there has been very limited information concerning the molecular geometry and conformation of biogenic monoamines and this lack of knowledge has seriously hampered efforts to unravel the structure—function relationships at the molecular level. Nevertheless, several theories have been proposed regarding interaction between the monoamines and their receptor sites. This is especially true for the neurohumoral transmitters dopamine, noradrenaline (norepinephrine) and serotonin (5-hydroxytryptamine), the target areas of which seem to be specific not only in the sense of chemical structure but also from the steric point of view. The well-known differences in biological activity due to chiralty illustrate the importance of the three-dimensional architecture of the molecules and indicate also the presence of stereospecific receptor sites. A detailed knowledge of the conformation of the biogenic monoamines would not only elucidate the requirements upon a natural or synthetic monoamine for proper function but also give indirect information about the geometry of the receptor sites.