Cloquinozine is a quinazoline derivative discovered by Japanese company Chugai Pharmaceutical in the 1960s. Cloquinozine has oxytocic properties and induces uterine contractions when administered to rabbits intravenously at 1 mg/kg.

Pheneridine is a synthetic opioid. It was developed as a narcotic agent.

Brifentanii, a potent narcotic analgesic structurally similar to alfentanil, that was studied in clinical trials in the early 1990s. The effects of brifentanil are very similar to those of alfentanil, with strong but short lasting analgesia and sedation, and particularly notable itching and respiratory depression. Side effects of Brifentanii are similar to those of fentanyl itself, which include itching, nausea and potentially serious respiratory depression, which can be life-threatening.

KETORFANOL, a morphinan derivative, is an opioid analgesic. It showed potent antiwrithing activity in the animal assay. It was equipotent with morphine as an agonist and lacked antagonist activity up to 10 mg/kg.

Conessine is a plant steroid alkaloid that acts as a potent and specific antagonist of histamine H3 receptors. Conessine displayed high affinity at both rat and human H3 receptors (pKi = 7.61 and 8.27) and generally high selectivity against other sites, including histamine receptors H1, H2, and H4. Conessine was found to efficiently penetrate the CNS and reach very high brain concentrations. Although the very slow CNS clearance and strong binding to adrenergic receptors discouraged focus on conessine itself for further development, its potency and novel steroid-based skeleton motivated further chemical investigation. Modification based on introducing diversity at the 3-nitrogen position generated a new series of H3 antagonists with higher in vitro potency, improved target selectivity, and more favorable drug-like properties. Conessine also has high affinity for the adrenergic receptors. Conessine has being shown to possess anti-malarial activity. In India conessine finds therapeutic use for treatment of dysentery and helminthic disorders.

Propisergide is a lysergic acid derivative patented by Sandoz Ltd. as an α-adrenoceptor-blocking agent with marked specific 5-HT receptor antagonist activity. In preclinical trials, Propisergide inhibited tryptamine tremor in rats and adrenaline-induced aggregation of blood platelets.

Securinine is a plant-derived alkaloid from the Securinega plant that has been used clinically as a therapeutic for primarily neurological related diseases. Securinine is well-known GABAA antagonist and recently it was found that Securinine is able to up-regulate p53 protein and to modulate the related family member p73 protein in a p53-dependent fashion, inducing p73 in the HCT116 p53(-) cells and down-regulating it in the p53(+) cells. Securinine induces G1 phase cell cycle arrest, upregulates expression of p53 and Bax, and downregulates expression of Bcl-2, PI3K, mTOR, and p70s6k in breast cancer cells and promyelocytic leukemia cells. Securinine activates p38 MAPK, enhancing monocyte antibacterial activity in vitro as well. This compound also exhibits antimicrobial activity against Alternaria, Curvularia, and Helminthosporum. Additionally, securinine decreases AChE activity and suppresses amyloid-β (Aβ)-induced glial inflammatory responses in animal models of Alzheimer’s disease, improving cognitive deficits. Securinine’s activity as a GABA antagonist, likely explains its reported clinical success in limited studies for the treatment of neurological conditions such as amyotrophic lateral sclerosis (ALS), poliomyelitis and multiple sclerosis. Securinine has not been utilized in the United States, it has been used clinically in several other countries particularly China and Russia. In China, it is considered one of the 50 fundamental Chinese herbs and is used in Chinese herbal medicine.

Vintriptol, a tryptophan ester of vinblastine, was developed as an antitumor drug. Vintriptol participated in a phase I clinical trial for the treatment of non-small cell lung cancer. As a result, was found a recommended dose for stage II. However, the further development of vintriptol was discontinued.

Vinleurosine is a vinca alkaloid found in species of Catharanthus. This compound was studied as an anticancer agent and participated in clinical trials. However, the drug was more toxic and unpredictable in effect in comparison with vinblastine. Its further development was discontinued.