Hebei Kaiyou Biological Technology Co, Ltd

U-47700, street name pinky or pink, is an opioid analgesic rndrug developed by a team at Upjohn in the 1970sthat acts as a selective agonist rnof the µ-opioid receptor with a Kd value of 5.3 nM compared to 910 nM for the rnκ-opioid receptorand has around 7.5 x the potency of morphine in animal rnmodels

U-47700 is a structural isomer of the earlier opioid rnAH-7921and the result of a great deal of work elucidating the quantitative rnstructure–activity relationship of the scaffold. Upjohn looked for the key rnmoieties which gave the greatest activityand posted over a dozen patents on rnrelated compounds, each optimizing one moiety until they discovered that U-47700 rnwas the most active.

U-47700 became the lead compound of selective kappa-opioid rnreceptor ligands such as U-50488, U-51754 (containing a single methylene spacer rndifference) and U-69,593, which share very similar structures. Although not used rnmedically, the selective kappa ligands are used in research.