Imidocarb is a carbanilide derivative with antiprotozoal activity. It is usually administered as the dipropionate salt. Imidocarb is a drug sold under the brand name Imizol and is used to treat canine ehrlichiosis. wo mechanisms of action have been proposed: As the effect of imidocarb on Trypanosoma brucei is antagonized by excess polyamines, it is has been suggested that imidocarb interferes with their production and/or use. Imidocarb blocks the entry of inositol into erythrocytes containing Babesia, resulting in starvation of the parasite. It is generally accepted in that imidocarb has anticholinesterase activity.

An alkaloid found in opium but not closely related to the other opium alkaloids in its structure or pharmacological actions. Papaverine is a vasodilating agent. Papaverine is used for the treating certain conditions that are accompanied by smooth muscle spasms (eg, blood vessel, urinary, gallbladder, or intestinal spasm). Papaverine is a nonxanthine phosphodiesterase inhibitor for the relief of cerebral and peripheral ischemia associated with arterial spasm and myocardial ischemia complicated by arrhythmias. The main actions of Papaverine are exerted on cardiac and smooth muscle. Like qathidine, Papaverine acts directly on the heart muscle to depress conduction and prolong the refractory period. Papaverine relaxes various smooth muscles. This relaxation may be prominent if spasm exists. The muscle cell is not paralyzed by Papaverine and still responds to drugs and other stimuli causing contraction. The antispasmodic effect is a direct one, and unrelated to muscle innervation. Papaverine is practically devoid of effects on the central nervous system. Papaverine relaxes the smooth musculature of the larger blood vessels, especially coronary, systemic peripheral, and pulmonary arteries. Papaverine is a potent, specific inhibitor of PDE10A. Papaverine for treatment of erectile dysfunction (ED) is excluded from coverage.

Malachite green, an N-methylated diaminotriphenylmethane dye, is used primarily as a therapeutic agent in aquaculture. It controls fungal attacks, protozoan infections and some other diseases caused by helminths on a wide variety of fish and other aquatic organisms. In solution, the dye exists as a mixture of the cation (chromatic malachite green) and its carbinol base, with the ratio depending on the pH of the solution; the dye also can undergo chemical and metabolic reduction to a leuco derivative. Malachite green intercalates with DNA, with a preference for A:T-rich regions, and the leuco derivative bears a structural resemblance to carcinogenic aromatic amines that can form covalent DNA adducts. In mammalian cells, it shows marked cytotoxicity and the ability to induce cell transformation and lipid peroxidation. The toxicity of this dye increases with exposure time, temperature and concentration. It has been reported to cause carcinogenesis, mutagenesis, chromosomal fractures, teratogenecity and respiratory toxicity.

Dipyrone, also known as Metamizole (INN), is an ampyrone sulfonate analgesic, antispasmodic and antipyretic. It was withdrawn from US market in 1977 on the basis of reports of agranulocytosis. Depyrone is still used to treat severe and diffucult for relieving pains of different origin; headache, tooth-ache, pains in the joints, muscles, following traumas and operations, gall and kidney colics, neurites, neuralgias, traumatic cerebrasthenia; inflammation of upper respiratory ways of microbial or virus origin; chorea; febrile states. Mechanism of action of dipyrone is complex. It is believed that dipyrone exerts its action by inhibiting COX-3, and activates opioid and cannabioid systems either itself, or by products of its metabolic degradation.

Prenylamine, a slow Ca2+ channel blocker, was used to treat patients with angina pectoris, but because of the QT prolongation, this drug was withdrawn from the market. Prenylamine binds to calmodulin section and inhibits myosin light chain kinase.

Ipriflavone (chemical structure: 7-isopropoxyisoflavone), derived from the soy isoflavone, daidzein, holds great promise for osteoporosis prevention and treatment. Ipriflavone (IP) was discovered in the 1930s but has only recently begun to be embraced by the medical community in this country. Over 150 studies on safety and effectiveness, both animal and human, have been conducted in Italy, Hungary, and Japan. As of 1997, 2,769 patients had been treated a total of 3,132 patient years. Preliminary studies have pointed to its effectiveness in the treatment of other conditions involving bone pathology, including Paget’s disease, hyperparathyroidism, renal osteodystrophy, and tinnitus due to otosclerosis. Ipriflavone appears to have several mechanisms of action, all of which enhance bone density, making them seemingly superior to many of the other treatments available for osteoporosis prevention and treatment. IP also inhibits osteoclastic activity (motility and resorptive activity) by modulating intracellular free calcium. IP’s bone-forming mechanisms include stimulation of cell proliferation and maturation of osteoblasts by inhibiting calcium influx into osteoblasts and phosphoinositide hydrolysis. Despite similarities to estrogen, IP possesses no intrinsic estrogenic activity, but does potentiate estrogen. Importantly, IP does not change bone mineral composition or crystalline structure. A clinical trial reported in 2001 that it was not effective in prevention or treatment of osteoporosis.

Batebulast (NCO-650) is an anti-allergic drug. It significantly inhibited both the initial and secondary increases in cAMP stimulated by antigen, anti-IgE and concanavalin A (Con A) in rat peritoneal mast cells. It strongly inhibited the incorporation of the 3H-methyl moiety into phospholipid by antigen, anti-IgE and Con A during histamine release. Batebulast significantly inhibited the compound 48/80-induced bronchoconstriction in dogs. Batebulast had no effect on the bronchoconstriction induced by inhalation of acetylcholine, suggesting that NCO-650 appears to have no anti-cholinergic effect and thus no effect on the vagal reflex that occurred during the asthmatic responses. NCO-650 may be useful for the treatment of bronchial asthma as an orally active drug. Batebulast has been in phase II clinical trials for the treatment of asthma in Japan. However, this research has been discontinued.

Levormeloxifene (INN) is an experimental selective estrogen receptor modulator (SERM) that was being developed as an alternative to estrogen replacement therapy for the treatment and prevention of postmenopausal bone loss. Levormeloxifene is the levorotatory enantiomer of non-hormonal, non-steroidal oral contraceptive -- ormeloxifene (trade names Novex-DS, Centron, and Sevista). The development of Levormeloxifene was stopped because of a high incidence of gynecologic adverse events during clinical trials.