175205-14-8Relevant articles and documents
1-[2-methoxy-5-(3-phenylpropyl)]-2-aminopropane unexpectedly shows 5-HT2A serotonin receptor affinity and antagonist character
Rangisetty,Dukat,Dowd,Herrick-Davis,DuPre,Gadepalli,Teitler,Kelley,Sharif,Glennon
, p. 3283 - 3291 (2007/10/03)
Certain phenylethylamines, such as 1-(4-bromo-2,5-dimethoxyphenyl)-2-aminopropane (DOB; 1a), are high-affinity 5-HT2 agonists. Previous structure - affinity studies have concluded that both the 2,5-dimethoxy substitution pattern and the nature of substituents at the 4-position are important determinants of high affinity. We recently demonstrated that replacement of the bromo group of DOB with a 3-(phenyl)propyl substituent results in retention of affinity and that, counter to established structure - affinity relationships, the 2,5-dimethoxy substitution pattern is no longer a requirement for the binding. The present investigation extends these findings by examining a series of analogues, 3, lacking a 5-methoxy group. It was additionally found that shifting the phenylalkyl substituent from the 4- to the 5-position (e.g., 4i) also results in retention of affinity. For example, 1-(2-methoxy-5-(3-phenylpropyl)-2-aminopropane (6; the α-methyl derivative of 4i) binds at 5-HT2A receptors with high affinity (Ki = 13 nM) and possesses 5-HT2A antagonist character. Thus, not only is the 2,5-dimethoxy substitution pattern not a requirement for the binding of certain phenylethylamines at 5-HT2A receptors, the presence of a 4-position substituent (previously thought to serve as a modulator of affinity of DOB-like agents) is also not required. Striking differences in the 5-HT2A binding requirements of the present compounds as compared to DOB-like agents suggest multiple substituent-dependent modes of binding.