Proxorphan is a N-substituted 6-oxamorphinane patented by American pharmaceutical company Bristol-Myers Co. as opioid analgesic and antitussive drug. Proxorphan acts as a κ-opioid receptor partial agonist and to a lesser extent as a μ-opioid receptor partial agonist.

Vinfosiltine (also known as S 12363) was developed as a vinca alkaloid derivative. It is known that vinca alkaloids are widely used in the medical treatment of breast cancer. Vinfosiltine participated in the phase II clinical trial to treat the patients with advanced breast cancer. The results have shown that the drug didn’t have significant single-agent activity. As a result, the development of vinfosiltine was discontinued.

Betameprodine is an opioid analgesic under international control according to the UN Single Convention 1961. The stereoisomer alphameprodine was more widely used, however, had a similar classification.

Desocriptine is an ergot alkaloid (alpha-dihydro-beta-ergocryptine) derivative. It is a combined alpha- and beta-adrenoceptor antagonist. Desocriptine is antihypertensive and antianginal agent.

Vinzolidine (also known as LY104208), a semisynthetic vinblastine derivative that was developed as an antitumor agent. Vinzolidine participated in clinical trials phase II in the oral formulation in patients with lymphoma, particularly Hodgkin's disease. In addition, it was studied in patients with Kaposi's sarcoma, non-small cell lung cancer, colorectal cancer, and breast cancer. It was found significant side effects included neurotoxicity and dose-related myelosuppression. As a result, was suggested intravenous route of administration for vinzolidine could be more safely. However, the phase I trial of intravenous vinzolidine was shown no antitumor activity. The further development of this drug was discontinued.

Vinepidine, a derivative of vincristine participated in clinical trials as an antineoplastic agent. As a result, the extreme neuromuscular toxicity was observed, that is why this study was discontinued.

Vinrosidine (leurosidine) is a leurosine-like alkaloid originally isolated from Vinca rosea Linn. Vinrosidine exerts antitumor activity in animal models.

Xorphanol (also known as TR5379M) is a full κ-opioid receptor agonist and is a partial agonist at μ opioid receptor. Clinically, xorphanol was studied as an orally active analgesic that provided effective pain relief but showed low physical dependence liability. Further development of this drug was discontinued.

Dimethylthiambutene is the synthetic narcotic analgesic agent. It has analgesic effect similar to those of meperidine. The (+)-enantiomer of dimethylthiambutene is more active than the (-)-isomer. Dimethylthiambutene clinically compared with meperidine (pethidine), but maintains the dependence-producing capability of morphine. It has had illicit use in Japan in the past. Dimethylthiambutene is under international control according to the UN Single Convention 1961 and its amendments, Schedule I.

Phenadoxone hydrochloride is one of some forty amino-ketones and amino-esters related to amidone. The compound is a very potent analgesic for the rat; by the subcutaneous route it is more active than either morphine or amidone. In spite of this its acute toxicity to mice is lower than that of amidone and its therapeutic index is therefore correspondingly higher, giving a wider margin of safety. Side effects in dogs, such as narcosis, sedation, and general depression, were much less with phenadoxone than with amidone or morphine. Nausea and vomiting did not occur after phenadoxone in non-tolerant dogs. Clinical results show that for relieving certain types of pain in human subjects it is a potent analgesic that compares favorably with morphine and amidone. At therapeutic dose levels undesirable pharmacological effects, such as cardiac depression and vasomotor disturbance, are absent, and it is only at extremely high dose levels that untoward effects occur. However, the drug has a strong respiratory depressant action when given in high doses; it should be used with special caution if injected intravenously.