Solution and crystal structure of cytisine, a quinolizidine alkaloid

The solution and crystal structure of the alkaloid cytisine has been studied using n.m.r. techniques and X-ray crystallography respectively. 1H and 13C relaxation parameters and coupling constants have been used to (i) study the motion of cytisine in solution and (ii) measure interatomic distance and dihedral angles. Agreement, within experimental error, has been found between the solution and crystal parameters.