Chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile) is an organic compound mainly used as a broad spectrum, nonsystemic fungicide, with other uses as a wood protectant, pesticide, acaricide, and to control mold, mildew, bacteria, algae. Chlorothalonil reduces fungal intracellular glutathione molecules to alternate forms which cannot participate in essential enzymatic reactions, ultimately leading to cell death. Chlorothalonil is slightly toxic to mammals, but it can cause severe eye and skin irritation in certain formulations. Very high doses may cause a loss of muscle coordination, rapid breathing, nose bleeding, vomiting, and hyperactivity. Dermatitis, vaginal bleeding, bright yellow and/or bloody urine, and kidney tumors may also occur, followed by death. In a number of tests of varying lengths of time, rats which were fed a range of doses of chlorothalonil generally showed no effects on physical appearance, behavior, or survival. Kidney changes such as kidney enlargement were common. In the US, chlorothalonil is used predominantly on peanuts (about 34% of usage), potatoes (about 12%), and tomatoes (about 7%), though the EPA recognizes its use on many other crops. It is also used on golf courses and lawns (about 10%) and as a preservative additive in some paints (about 13%), resins, emulsions, and coatings. Chlorothalonil is commercially available in many different formulations and delivery methods. It is applied as a dust, dry or water-soluble grains, a wettable powder, a liquid spray, a fog, and a dip. It may be applied by hand, by ground sprayer, or by aircraft

PU-H71 is experimental inhibitor of Hsp90. It is being tested in clinical trials against lymphoma and solid tumors.

Thimerfonate is a alkyl mercuric derivative with germicidal activity.

APTO-253 is a novel small molecule that can induce expression of the genes that code for the Krüppel-like factor 4 (KLF4) master transcription factor and for the p21 cell cycle inhibitor protein, and can inhibit expression of the c-Myc oncogene, leading to cell cycle arrest and programmed cell death (apoptosis) in human-derived solid tumor and hematologic cancer cells. A Phase 1 study with APTO-253 was completed and demonstrated modest clinical activity in patients with colon cancer, acute leukemia, myelodysplastic syndrome, hematological malignancies and non-small cell lung cancers.

Annamycin is a highly lipophilic form of the anthracycline doxorubicin with the ability to bypass multidrug resistance mechanisms of cellular drug resistance. Annamycin belongs to the anthracycline class of drugs, and has a pleiotropic mechanism of action where it targets topoisomerase II, causing strand breaks in DNA. Annamycin forms complexes with DNA by intercalation between base pairs, and it inhibits topoisomerase II activity by stabilizing the DNA-topoisomerase II complex, preventing the religation portion of the ligation-religation reaction that topoisomerase II catalyzes. The agent is being evaluated in separate phase 1 and phase 2 trials in the United States and Europe. Studies in animal models showed the agent to be noncardiotoxic. Trials that included patients with leukemia showed the agent was associated with fewer dose-limiting toxicities than typically experienced with doxorubicin. The FDA granted fast track designation to Annamycin for treatment of patients with relapsed or refractory acute myeloid leukemia.

Parafluorofentanyl is a selective mu-opioid agonist, an analog of fentanyl, developed by Janssen. The drug was not developed for human use but is produced and abused illegally.

MPEP (2-methyl-6-(phenylethynyl)pyridine) was one of the first compounds found to act a selective antagonist for the metabotropic glutamate receptor subtype mGluR5. It was under development by Novartis in the late 1990's. MPEP was found to produce neuroprotective effects following acute brain injury in animals. MPEP was also found to have positive effects on animal models of depression, anxiety and morphine withdrawl.

SNS-032 (formerly BMS-387032) is a potent, selective inhibitor of cyclin-dependent kinases (CDK). SNS-032 blocks the cell cycle via inhibition of CDKs 2 and 7, and transcription via inhibition of CDKs 7 and 9. SNS-032 was investigated for the treatment of solid tumors and hematologic malignancies (Phase I studies), however, its development was discontinued.

Avelestat, also known as AZD9668, is a novel, oral inhibitor of neutrophil elastase (NE), an enzyme implicated in the signs, symptoms, and disease progression in NE-driven respiratory diseases such as bronchiectasis, Cystic Fibrosis and chronic obstructive pulmonary disease via its role in the inflammatory process, mucus overproduction, and lung tissue damage. Its development was discontinued due to unknown reasons. Nevertheless, this drug in the phase II of clinical trial as adjunctive therapy in improving insulin sensitivity of insulin-resistant type 2 diabetic subjects. The drug's clinical profile suggests that it will be well tolerated with few, if any, side effects, and the existence of simple methods that can indirectly measure its activity in vivo.

Mavoglurant (AFQ056) was developed as a new metabotropic glutamate receptor 5 (mGluR5) antagonist. The efficacy of mavoglurant in humans has been assessed in L-dopa induced dyskinesia in Parkinson's disease and Fragile X syndrome in proof of principle clinical studies. However, Novartis had announced that the company would be discontinuing its development program in Fragile X following negative results in a large international clinical trial in adults, and more recently in a trial in adolescents. In both placebo-controlled trials, patients taking mavoglurant did not show improvement over placebo in any outcome measures. In patients with L-Dopa-induced dyskinesias studies failed to meet the primary objective of demonstrating improvement of dyskinesia. Mavoglurant was also investigated in phase II clinical trials to reduce chorea in Huntington's disease, but the target result was not achieved. Currently Novartis is conducting a phase II clinical trial to demonstrate whether or not this drug can benificially reduce cocaine use in Cocaine Use Disorder.