Methyl cyclohexanecarboxylate is an endogenous metabolite and used as a material for chemical synthesis.

N3-Ph-NHS ester is a noncleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs).

Porcine dynorphin A (1-13) is a potent, endogenous κ opioid receptor agonist and is antinociceptive at physiological concentrations. Exposure to dynorphin A (1-13) causes acute increases in [Ca2+]i in individual neurons similar to increases seen with acute NMDA treatment.