Somnifericin is a natural product for research related to life sciences.

Men 10376 is a selective tachykinin NK-2 receptor antagonist, with a Ki of 4.4 μM for rat small intestine NK-2 receptor.

[Met5]-Enkephalin, amide is an agonist for δ opioid receptors as well as putative ζ (zeta) opioid receptors.Met-enkephalin circulates in several forms, some of which may be derived from proteins other than proenkephalin A, and plasma levels of both free native, and peptidase-derivable Met-enkephalin are modulated physiologically.