Pentamorphone was developed as a highly potent opioid with rapid onset and short duration of action that has been reported to produce analgesia with limited depression of ventilation. Pentamorphone participated in a clinical trial for the management of postoperative pain. However, no acute cardiorespiratory changes were observed. The drug was ineffective for treating acute postoperative pain after major surgery. In addition, was shown that pentamorphone, 10 micrograms/kg, does not seem to offer any significant advantage over opioids currently used for anesthesia in patients undergoing elective coronary artery bypass grafting (CABG). That is why its further development was discontinued.

Tomelukast (previously known as LY171883), an orally active antagonist of the CysLT1 receptor (leukotriene D4), which was investigated to treat asthma, but this study was discontinued because of adverse gastrointestinal effect.

Endothal (also known as Endothall), a herbicide for terrestrial and aquatic plants, is a potent, selective protein phosphatase 2A (PP2A) inhibitor. It also inhibits protein phosphatase 1 (PP1). Endothall is considered safe in drinking water, but in case of consumption for a long period, it can cause stomach or intestinal problems.

Medroxalol is a competitive antagonist at alpha1-adrenergic receptors and beta1-adrenergic receptors. Medroxalol also an agonist at beta2-adrenergic receptors. Medroxalol exerts antihypertensive and vasodilating effects. It was concluded that the principal action of medroxalol was to produce a fall in blood pressure by decreasing peripheral vascular resistance more than cardiac output.

Zometapine was developed as an antidepressant drug. This drug participated in phase II clinical trial in patients with depression where it showed as an effective agent. However, information about the further development of Zometapine is not available.

Tolimidone, Lyn protein-tyrosine kinase stimulant, is in phase II clinical by Melior Discovery and Bukwang for the treatment of type 2 diabetes. It is also in phase II clinical by Pfizer for the treatment of ulcer. However, this research has been discontinued.

Dezaguanine is a broad spectrum guanine antimetabolite. This compound differs from guanine only in the substitution of a carbon for the 3-nitrogen of guanine. Dezaguanine must be converted to its nucleotides to be active. Dezaguanine nucleotides inhibit synthesis of guanine nucleotides, and can be incorporated into nucleic acids in place of guanine nucleotides; incorporation into DNA may be particularly important in the cytotoxicity of this compound. Addition of certain purines or purine nucleosides can prevent dezaguanine cytotoxicity in vitro. It has exhibited sufficient preclinical antitumor activity, particularly against rat and mouse mammary adenocarcinomas, slow and fast growing mammary tumors in mice and the human breast xenograft subrenal capsule implant system. It has completed one phase I trial.

Information related to the biological and/or pharmacological activity of glyoctamide is absence. Only one mention exists, describing, that this compound was developed as the antidiabetic agent by Hoechst Roussel Pharm. Inc

N,N-Dimethyl-5-Methoxytryptamine (aka 5-MeO-DMT) is a psychedelic of the tryptamine class. It is found in a wide variety of plant species, and a single psychoactive toad species, the Colorado River toad. Like its close relatives DMT and bufotenin (5-HO-DMT), it has been used as an entheogen in South America. It can also be found in the dart poison traditionally used by the Yanoama Indians of Upper Orinoco. It acts as a non-selective serotonin (5-HT) agonist. -MeO-DMT is O-demethylated by polymorphic cytochrome P450 2D6 (CYP2D6) to an active metabolite, bufotenine. 5-MeO-DMT is classified as a controlled substance in China, Australia, Sweden, Turkey, and the USA.

16,16-dimethyl Prostaglandin E2 acts as an agonist on most prostaglandin E (EP) receptor subtypes, it has prolonged half-life in vivo, because it is not a substrate for the enzyme 15-hydroxy prostaglandin dehydrogenase. This compound was studied by Fate Therapeutics in phase I clinical trials under the name FT1050 or ProHema-CB for pediatric patients with hematologic malignancies. However, this study was terminated.