Conjugated enynes as nonaromatic catechol bioisosteres: Synthesis, bindingexperiments, and computational studies of novel dopamine receptor agonistsrecognizing preferentially the D-3 subtype
H. Hubner et al., Conjugated enynes as nonaromatic catechol bioisosteres: Synthesis, bindingexperiments, and computational studies of novel dopamine receptor agonistsrecognizing preferentially the D-3 subtype, J MED CHEM, 43(4), 2000, pp. 756-762
To evaluate nonaromatic catechol bioisosteres, the conformationally restrai
ned enynes 1 and enediynes 2 were synthesized via palladium-catalyzed coupl
ing as the key reaction step. Subsequent receptor binding studies at the do
pamine receptor subtypes D-1, D-2 long, D-2 short, D-3, and D-4 showed high
ly interesting binding profiles for the enynes la and 1b when compared to d
opamine. At the guanine nucleotide-sensitive high-affinity binding site of
the Da receptor, the target compound 1b (K-i = 5.2 nM) was 10-fold more pot
ent than dopamine but less potent at the D-2 and D-4 subtypes. In contrast
to dopamine the agonists la and Ib showed strong selectivity for the recept
ors of the D-2 family (D-2-D-4) As far as We know, this study represents th
e first report on nonaromatic dopamine agonists. Comparison of molecular el
ectrostatic potentials, derived from semiempirical molecular orbital calcul
ations, and lipophilicity maps was performed.