Opioid Receptor Control

N-terminally acetylated Endomorphin-1 is a modified Endomorphin-1.

Moguisteine???(BBR-2173) is an antitussive compound but has no significant affinity for opiate receptors.

(S)-Laudanosine is an alkaloid that can be found in poppies and is the S-enantiomer of Laudanosine. Laudanosine acts on the central nervous system and cardiovascular system, inhibiting low-affinity GABA receptors with an IC₅₀ value of 10 μM, and can cause seizures, hypotension, and bradycardia. Additionally, Laudanosine exerts analgesic effects by competitively binding to the opioid Mu-1 receptor (K_i = 2.7 μM).

Bilaid B (compound 2a) is a tetrapeptide. Bilaid B resembles opioid peptides albeit with a unique, alternating LDLD amino acid configuration. .

AH-8533 is a opioid agent.

Kentsin (Thr-Pro-Arg-Lys), a contraceptive tetrapeptide, is originally extracted from hamster embryos. Kentsin prevents the maturation of Graafian follicles and consequently inhibits ovulation, without binding to opioid receptors. Kentsin has opiate properties on gastrointestinal motility.

Isopaynantheine (3-Isopaynantheine), an alkaloid, is an opioid. Isopaynantheine has antinociceptive activity in mice.