several other compounds , both agonists and antagonists , have been examined , and it is concluded that ( i ) the nmda receptor reacts preferentially with substances in a relatively extended configuration , ( ii ) the glutamate/quisqualate receptor prefers folded molecules and ( iii ) the distance separating the amino group from the distal anionic function is the critical one determining receptor preference .
C0021966
i
C0003075
anionic