2, 3-Dihydrobenzofuran Analogues of Hallucinogenic Phenethylamines

David E. Nichols, Scott E. Snyder, Robert Oberlender, Michael P. Johnson, Xuemei Huang

Research output: Contribution to journalArticle

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Abstract

Two 2,3-dihydrobenzofuran analogues of hallucinogenic amphetamines were prepared and evaluated for activity in the two-lever drug-discrimination paradigm in rats trained to discriminate saline from LSD tartrate (0.08 mg/kg) and for the ability to displace [125I]-(R)-DOI ([125I]-(R)-1-(2, 5-dimethoxy-4-iodophenyl)-2-aminopropane) from rat cortical homogenate 5-HT2 receptors. The compounds, l-(5-methoxy-2, 3-dihydrobenzofuran-4-yl)-2-aminopropane (6a) and its 7-brominated analogue 6b, possessed activity comparable to their conformationally flexible counterparts 1 -(2, 5-dimethoxyphenyl)-2-aminopropane (3) and its 4-bromo derivative DOB (5), respectively. The results suggest that the dihydrofuran ring in 6a and 6b models the active conformation of the 5-methoxy groups in 3 and 5. Free energy of binding, derived from radioligand displacement KA values, indicated that addition of the bromine in either series contributes 2.4-3.2 kcal/mol of binding energy. On the basis of surface area of the bromine atom, this value is 2-3 times higher than would be expected on the basis of hydrophobic binding. Thus, hydrophobicity of the para substituent alone cannot account for the dramatic enhancement of hallucinogenic activity. Although this substituent may play a minor role in orienting the conformation of the 5-methoxy group in derivatives such as 4 and 5, there appears to be some other, as yet unknown, critical receptor interaction.

Original languageEnglish (US)
Pages (from-to)276-281
Number of pages6
JournalJournal of Medicinal Chemistry
Volume34
Issue number1
DOIs
StatePublished - Jan 1 1991

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Phenethylamines
Bromine
Amphetamines
Lysergic Acid Diethylamide
Hydrophobic and Hydrophilic Interactions
Pharmaceutical Preparations
coumaran
4-iodo-2,5-dimethoxyphenylisopropylamine
tartaric acid
2,5-dimethoxyamphetamine

All Science Journal Classification (ASJC) codes

  • Molecular Medicine
  • Drug Discovery

Cite this

Nichols, David E. ; Snyder, Scott E. ; Oberlender, Robert ; Johnson, Michael P. ; Huang, Xuemei. / 2, 3-Dihydrobenzofuran Analogues of Hallucinogenic Phenethylamines. In: Journal of Medicinal Chemistry. 1991 ; Vol. 34, No. 1. pp. 276-281.
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2, 3-Dihydrobenzofuran Analogues of Hallucinogenic Phenethylamines. / Nichols, David E.; Snyder, Scott E.; Oberlender, Robert; Johnson, Michael P.; Huang, Xuemei.

In: Journal of Medicinal Chemistry, Vol. 34, No. 1, 01.01.1991, p. 276-281.

Research output: Contribution to journalArticle

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