Chlorogenic acid is the ester of caffeic acid and (-)-quinic acid. Chlorogenic acid is a naturally occurring plant metabolite and can be found with the related compounds cryptochlorgenic acid and neochlorogenic acid in the leaves of Hibiscus sabdariffa, coffee, potato, eggplant, peaches, and prunes. Chlorogenic acid has been investigated as a dietary supplement to improve glucose intolerant hypoglycemia and non-alcoholic fatty liver disease. It has also been identified as a potential anticancer agent by reducing the expression of HIF-1a and Sphingosine Kinase-1. Chlorogenic acid was also identified as a neuraminidase blocker effective against influenza A virus (H1N1 and H3N2).

Omtriptolide (previously known as PG490-88 or F60008), an immunosuppressant that has been shown to be the safe and potent antitumor agent and it has been approved entry into Phase I clinical trial for the treatment of prostate cancer in the USA. In addition, the drug is participating in phase I clinical trial for the treatment of myeloid leukemia. Experiments on animals have shown omtriptolide was highly effective in the prevention of murine graft-versus-host disease (GVHD). The immunosuppressive effect of the drug was mediated by inhibition of alloreactive T cell expansion through interleukin-2 production. However, this study was discontinued. Recently published article has shown omtriptolide possesses the potential as a prophylactic agent to prevent ischemia/reperfusion (I/R)-induced lung injury.

Avagacestat (BMS-708163) is an oral gamma secretase inhibitor designed for selective inhibition of amyloid beta (Aβ) synthesis. Avagacestat was in development by Bristol-Myers Squibb for the treatment of Alzheimer's disease (AD). Avagacestat is a potent, selective, orally bioavailable γ-secretase inhibitor of Aβ40 and Aβ42 with IC50 of 0.3 nM and 0.27 nM, demonstrating a 193-fold selectivity against Notch. In November 2012, Bristol-Myers Squibb terminated clinical trials of the drug and announced its decision to end further development of avagacestat

Raxatrigine also known as GSK1014802 and CNV-1014802, is a novel analgesic under development by Convergence Pharmaceuticals for the treatment of lumbosacral radiculopathy (sciatica) and trigeminal neuralgia (TGN). It is a novel state dependent small molecule sodium channel blocker that preferentially inhibits the Nav 1.7 ion channel, a therapeutic target implicated by genetics in human pain conditions. Raxatrigine is thought to penetrate the central nervous system and block Nav channels in a novel manner. CNV1014802 was granted orphan drug designation in 2013 by the US Food and Drug Administration (FDA) for the treatment of trigeminal neuralgia.

Quiflapon Sodium (MK-0591; (3-[1-(4-chlorobenzyl)-3-(t-butylthio)-5-(quinolin-2-yl-methoxy)- indol-2-yl]-2,2-dimethyl propanoic acid, previously L-686,708) had been in phase II clinical studies for the treatment of inflammatory bowel disease, but the study was discontinued later, because in spite of MK-591 markedly inhibited Leukotrienes (LT) biosynthesis, it did not differ significantly from placebo in clinical efficacy. Also was discovered, that MK-0591 may modify the airway changes associated with bronchial hyper responsiveness, as well as offer symptomatic relief in asthma. MK-0591 is a selective and specific 5-Lipoxygenase-activating protein (FLAP) inhibitor with an IC50 value of 1.6 nM in a FLAP binding assay. In additional, recently was discovered, that MK591 possesses all major attributes of a standard anti-metastatic agent with significant cancer-selective effect, and suggest that MK591 may turn out to be an effective agent for therapy of castration-resistant, bone-metastatic prostate cancer. Though details of the molecular underpinnings of the anti-metastatic action of MK591 are unknown at this time, this finding gives an opportunity for further exploration to better understand the signaling mechanisms involved by in vitro and in vivo experiments.

Ombrabulin is an experimental drug candidate discovered by Ajinomoto and further developed by Sanofi-Aventis for cancer treatment. Ombrabulin is a synthetic water-soluble analog of combretastatin A4, derived from the South African willow bush (Combretum caffrum), with potential vascular-disrupting and antineoplastic activities. Ombrabulin binds to the colchicine binding site of endothelial cell tubulin, inhibiting tubulin polymerization and inducing mitotic arrest and apoptosis in endothelial cells. As apoptotic endothelial cells detach from their substrate, tumor blood vessels collapse; the acute disruption of tumor blood flow may result in tumor necrosis. Ombrabulin has been used in trials studying the treatment of Sarcoma, Neoplasms, Solid Tumor, Neoplasms, Malignant, and Advanced Solid Tumors, among others. In January 2013, Sanofi said it discontinued development of Ombrabulin after disappointing results from phase III clinical trials.

Andrographolide, a diterpenoid, is known for its anti-inflammatory effects. It can be isolated from various plants of the genus Andrographis, commonly known as 'creat'. Andrographolide has been tested for its anti-inflammatory effects in various stressful conditions, such as ischemia, pyrogenesis, arthritis, hepatic or neural toxicity, carcinoma, and oxidative stress. Apart from its anti-inflammatory effects, andrographolide also exhibits immunomodulatory effects by effectively enhancing cytotoxic T cells, natural killer (NK) cells, phagocytosis, and antibody-dependent cell-mediated cytotoxicity (ADCC). The properties of andrographolide, such as its ability to induce apoptosis of cancer cells and inhibition of DTH, its anti-oxidative and cytoprotective effect, and its ability to enhance CTLs and NK cell activation makes it a potent antiviral agent. Andrographolide inhibited the growth of human breast, prostate, and hepatoma tumors. Andrographolide could be a potent anticancer agent when used in combination with other chemotherapeutic agents.

Perzinfotel (EAA-090) is a novel squaric acid amide derivative that has been identified as a potential treatment for ischemic brain damage resulting from stroke. EAA-090 is a competitive inhibitor at the NMDA-selective subtype of the glutamate receptor. The compound demonstrates potent inhibitory activity in both in vitro and in vivo models of NMDA-induced excitotoxicity and provides neuroprotective efficacy in several animal models of stroke. EAA-090 is unique among competitive NMDA antagonists in displaying a clear separation between predicted efficacious dose and doses that induce PCP-like psychotomimetic side effects in both animals and humans. This unique profile makes EAA-090 an exciting candidate for assessing the neuroprotective potential of the competitive NMDA mechanism.

Pumosetrag is a novel, orally active and selective 5-HT 3 agonist. It is a partial agonist in rats and guinea-pig and a full agonist in the mouse, suggesting important species differences in 5-HT3 receptor structure. Pumosetrag had been in phase II clinical trials for the treatment of gastroesophageal reflux disease and irritable bowel syndrome. No serious adverse events were reported. Diarrhea was not more common on the drug and only one subject experienced pruritus. All researches on this drug candidate are discontinued.

Zosuquidar (LY-335979) is an experimental antineoplastic drug. It is is a potent modulator of P-glycoprotein-mediated multi-drug resistance with Ki of 60 nM. Zosuqidar was initially characterized by Syntex Corporation, which was acquired by Roche in 1990. Roche licensed the drug to Eli Lilly in 1997. It was granted orphan drug status by the FDA in 2006 for AML. Zosuquidar Trihydrochloride had been in phase III clinical trials by Kanisa Pharmaceuticals for the treatment of acute myeloid leukaemia. However, this research has been discontinued.