N-Ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) is a dopamine-receptor antagonist.Neuroscience Letters 1992, 137(2), p.265

EEDQ is also a highly specific reagent for carboxyl groups. It enables the coupling of acylamino acids with amino acid esters in high yield and without racemization.https://www.bachem.com/

It is also an irreversible dopamine transporter (DAT) blocker in vitro, though it is ineffective in vivo.

References