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Updated: Jul 17, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Novel 4-(6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolin-2-yl)methylbenzofuran derivatives as selective
Koji Hagihara1, Hajime Kashima, Kyoichiro Iida
1Pharmaceutical Research Center, Kyowa Hakko Kogyo Co. Ltd., 1188 Shimotogari, Nagaizumi-cho, Sunto-gun, Shizuoka 411-8731, Japan. koji.hagihara@kyowa.co.jp
Abstract:
The synthesis of a series of 4-(6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolin-2-yl)methyl-2-arylbenzofuran and 4-(6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolin-2-yl)methylbenzofuran-2-carboxamide derivatives as novel alpha(2C)-adrenergic receptor antagonists are described. Their affinity at three different human alpha(2)-adrenergic receptors is reported, and some of these compounds exhibited high affinity for the alpha(2C)-adrenergic receptor with high subtype selectivity. Among them, compound 10e has been found to show the anti-L-dopa-induced dyskinetic activity in marmosets. The structure-activity relationship of these compounds is also discussed.
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