7-Arylidenenaltrexones as Selective δ<sub>1</sub> Opioid Receptor Antagonists
作者:Shigenori Ohkawa、Philip S. Portoghese
DOI:10.1021/jm980384s
日期:1998.10.1
A series of 7-arylidinenaltrexones (2a-m) related to the prototypical delta(1)-selective antagonist, 7-benzylidenenaltrexone 1 (BNTX), have been synthesized in an effort to develop more selective ligands. Testing in smooth muscle preparations revealed that members of the series exhibited varying degrees of selectively for delta receptors, with the o-methoxy (2e) and o-chloro (2j) congeners being most potent and most selective (Ke similar to 0.8 nm). Evaluation of 1, 2e, and 2f sc in mice using the tail-flick procedure indicated that they are selective delta(1) opioid receptor antagonists in the lower dose range. At high doses these ligands, including BNTX, exhibited decreased delta(1) selectivity due to increases in the ED50 ratios of [D-Ser(2),Leu(5)]enkephalin-Thr(6) and morphine. It is concluded that 2e and 2f possess in vivo selectivity similar to that of BNTX, but are less potent as delta(1) antagonists.
Antitrichomonal activity of δ opioid receptor antagonists, 7-benzylidenenaltrexone derivatives
The 7-benzylidenenaltrexone (BNTX) derivatives 2a–v, 3a–c, 13a–c, and 14a were synthesized from naltrexone (1) and evaluated for their antitrichomonal activity. The structure-activity-relationship studies found that 4-iodo-BNTX (2g) showed the highest activity (IC50 = 10.5 µM) and the affinity for the opioid receptor was less important for antitrichomonal activity against Trichomonas vaginalis. The