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Published on: September 20, 2016
Design and synthesis of KNT-127, a δ-opioid receptor agonist effective by systemic administration
Hiroshi Nagase1, Toru Nemoto, Ayaka Matsubara
1School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan. nagaseh@pharm.kitasato-u.ac.jp
Abstract:
We have reported previously the novel δ-opioid agonist, SN-28, which was more potent in in vitro assays than the prototype δ-agonists, TAN-67 and SNC-80. However, when administered by subcutaneous injection, this compound showed no analgesic effect at dosages greater than 30mg/kg in the acetic acid writhing test. We speculated that SN-28 was not effective in the test because the presence of the charged ammonium groups prevented its penetration through the blood-brain barrier. On the basis of our proposal, we designed the novel δ-agonist, KNT-127, which was effective with systemic administration.
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