Latrunculin B originates from Latrunculia (now Negombata) magnifica, a sponge from the Red Sea. Latrunculin B inhibits the assembly of actin microfilaments by 1:1 molecular binding of free actin monomers in the cell cytoplasm. It may be a potential therapeutic agent for glaucoma. Latrunculin B induced destabilization of the actin microfilament and apoptosis in a dose-dependent manner, as demonstrated by morphological changes and nuclear condensation in the PC3M cells. In addition, it resulted in an increase in the levels of gamma-H2AX recruitment, implicating the induction of DNA damage, including double-strand breaks. Induction of Bax, with little effect on Bcl-2 expression, indicated that actin disruption causes apoptosis through activation of Bax signaling in PC3M cells. This data might helps to develop the strategy for actin-based anticancer chemotherapy against highly metastatic prostate cancer.

Tipifarnib is an oral farnesyltransferase (FTase) inhibitor which was developed by Janssen (J&J). Upon administration, tipifarnib inhibits FTase and thus suppresses the activity of downstream effectors. The drug reached phase III of clinical trials for such diseases as pancreatic cancer (terminated), colorectal cancer (terminated) and acute myeloid leukemia (in elderly patients).

Taltobulin, also known as HTI-286 and SPA-110, is a fully synthetic analog of the natural tripeptide hemiasterlin, inhibits tubulin polymerization and circumvents transport-based resistance to taxanes. Taltobulin was a potent inhibitor of proliferation (mean IC50 = 4 nm in 18 human tumor cell lines) and had substantially less interaction with multidrug resistance protein (P-glycoprotein) than currently used antimicrotubule agents, including paclitaxel, docetaxel, vinorelbine, or vinblastine. Taltobulin showed strong antitumor activity both in androgen-dependent and androgen- independent tumors and may be a promising agent in second- line treatment strategies for patients suffering from docetaxel- refractory prostate cancer.

Allopregnanolone is a neurosteroid metabolite of progesterone. It is an allosteric modulator of inhibitory γ-aminobutyric acid (GABA-A) receptors on neural stem cells and other cell types in the brain. Allopregnanolone has effects similar to those of other positive allosteric modulators of the GABA action at GABAA receptor such as the benzodiazepines, including anxiolytic, sedative, and anticonvulsant activity. A solution of allopregnanolone, SAGE-547 is an intravenous allosteric modulator of both synaptic and extrasynaptic γ-aminobutyric acid type A (GABAA)receptors. It's believed that allopregnanolone is effective as an anticonvulsant when prolonged seizure activity has become resistant to benzodiazepine treatment. Under the names brexanolone and SAGE-547, allopregnanolone is under development by SAGE Therapeutics as an intravenously administered drug for the treatment of super-refractory status epilepticus, postpartum depression, and essential tremor. Allopregnanolone is in phase III trials for the treatment of super-refractory status epilepticus (SRSE) and postpartum depression.

Delavirdine is a nonnucleoside reverse transcriptase inhibitor (NNRTI). Delavirdine binds directly to reverse transcriptase (RT) and blocks RNA-dependent and DNA-dependent DNA polymerase activities. Delavirdine does not compete with template:primer or deoxynucleoside triphosphates. HIV-2 RT and human cellular DNA polymerases alfa, gamma, or delta are not inhibited by delavirdine. In addition, HIV-1 group O, a group of highly divergent strains that are uncommon in North America, may not be inhibited by delavirdine. Delavirdine is marketed under the trade name Rescriptor, indicated for the treatment of HIV-1 infection in combination with at least 2 other active antiretroviral agents when therapy is warranted. .

Fenoldopam (marketed under the brand name Corlopam) is a drug and synthetic benzazepine derivative which acts as a selective D1 receptor partial agonist. Fenoldopam is a rapid-acting vasodilator. It is an agonist for D1-like dopamine receptors and binds with moderate affinity to α2-adrenoceptors. It has no significant affinity for D2-like receptors, α1 and β adrenoceptors, 5HT1 and 5HT2 receptors, or muscarinic receptors. Fenoldopam is a racemic mixture with the R-isomer responsible for the biological activity. The R-isomer has approximately 250-fold higher affinity for D1-like receptors than does the S-isomer. Fenoldopam Mesylate Injection, USP is indicated for the in-hospital, short-term (up to 48 hours) management of severe hypertension when rapid, but quickly reversible, emergency reduction of blood pressure is clinically indicated, including malignant hypertension with deteriorating end-organ function.

Stavudine is a nucleoside reverse transcriptase inhibitor (NRTI) with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Stavudine is phosphorylated to active metabolites that compete for incorporation into viral DNA. They inhibit the HIV reverse transcriptase enzyme competitively and act as a chain terminator of DNA synthesis. The lack of a 3'-OH group in the incorporated nucleoside analogue prevents the formation of the 5' to 3' phosphodiester linkage essential for DNA chain elongation, and therefore, the viral DNA growth is terminated. Stavudine inhibits the activity of HIV-1 reverse transcriptase (RT) both by competing with the natural substrate dGTP and by its incorporation into viral DNA. Stavudine is used for the treatment of human immunovirus (HIV) infections. Stavudine is sold under the brand name Zerit among others.

Plicamycin (INN, also known as mithramycin; trade name Mithracin) is an antineoplastic antibiotic produced by Streptomyces plicatus. Plicamycin belongs to the group of medicines known as antineoplastics. It may be used to treat certain types of cancer. It is also used to treat hypercalcemia or hypercalciuria (too much calcium in the blood or urine) that may occur with some types of cancer. Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although this use is not included in product labeling, plicamycin is used in certain patients with the following medical condition:Paget's disease of the bone. The manufacturer discontinued plicamycin in 2000. Several different structures are currently reported in different places all with the same chromomycin core, but with different stereochemistry in the glycoside chain, a 1999 study has re-investigated the compound and proposed a revised structure. Although the exact mechanism by which Mithracin (plicamycin) causes tumor inhibition is not yet known, studies have indicated that this compound forms a complex with deoxyribonucleic acid (DNA) and inhibits cellular ribonucleic acid (RNA) and enzymic RNA synthesis. The binding of Mithracin (plicamycin) to DNA in the presence of Mg + + (or other divalent cations) is responsible for the inhibition of DNA-dependent or DNA-directed RNA synthesis. This action presumably accounts for the biological properties of Mithracin (plicamycin). Plicamycin may also lower calcium serum levels by inhibiting the effect of parathyroid hormone upon osteoclasts or by blocking the hypercalcemic action of pharmacologic doses of vitamin D.

Chlorpropamide (DIABINESE®), is a sulfonylurea hypoglycemic agent used in the treatment of non-insulin-dependent diabetes mellitus not responding to dietary modification. It appears to lower the blood glucose acutely by stimulating the release of insulin from the pancreas, an effect dependent upon functioning beta cells in the pancreatic islets. The mechanism by which chlorpropamide (DIABINESE®) lowers blood glucose during long-term administration has not been clearly established. Extra-pancreatic effects may play a part in the mechanism of action of oral sulfonylurea hypoglycemic drugs. While chlorpropamide is a sulfonamide derivative, it is devoid of antibacterial activity. Chlorpropamide (DIABINESE®) may also prove effective in controlling certain patients who have experienced primary or secondary failure to other sulfonylurea agent.

Reserpine is an alkaloid, isolated from the Rauwolfia serpentina plant and developed by Ciba pharma. Reserpine was approved by FDA for the treatment of hypertension and psychotic disorders. The drug exerts its effect by blocking two vesicular monoamine transporters, VMAT1 and VMAT2. The blockade results in vesicles that lose their ability to store neurotransmitter molecules. Neurotransmitters, thus retained in cytosol, are then neutralized by MAO.