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Updated: May 18, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Synthesis of quinolinomorphinan derivatives as highly selective δ opioid receptor ligands
Yoshihiro Ida1, Ayaka Matsubara, Toru Nemoto
1School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan.
Abstract:
We have reported previously the novel δ opioid agonist KNT-127 which showed high affinity and selectivity for the δ receptor. Moreover, the analgesic effect of subcutaneously administered KNT-127 was more potent than that of a prototypical δ agonist (-)-TAN-67 in the acetic acid writhing test. This study of the structure-activity relationship of KNT-127 derivatives focused on the introduction of substituents onto the 5'-, 6'-, 7'- or 8'-position of the quinoline ring and revealed that many derivatives with 5'- or 8'-substituents showed high affinities and selectivities for the δ receptor. Especially, SYK-153 with an 8'-OH group showed the highest affinity and the most balanced and highest selectivity for the δ receptor among the synthesized compounds.
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