(R)-Lercanidipine is enantiomer of antihypertensive drugs Lercanidipine, that acts by blocking L-type calcium channels, allowing relaxation and opening of blood vessels. The dihydropyridine calcium antagonists promote systemic vasodilatation by a reversible blockade of voltagedependent Ca2+ influx through L-type channels in the cell membrane. (S)-Lercanidipine has 100- to 200-fold greater affinity than the (R)-enantiomer for the L-type calcium channel. The pharmacokinectics of (S)- Lercanidipine has been evaluated in healthy volunteers, in elderly and non-elderly patients with hypertension, and in patients with renal or hepatic impairment. Patients from these studies were investigated after receiving a single 10 or 20 mgdose of [14C]-labeled rac-Lercanidipine as a solution. The maximum plasma concentrations of (S)-Lercanidipine were reached within 2–3 h and the area under the plasma concentration–time curves were not linearly related to the dose, indicating a saturable first-pass metabolism. The absorption of (S)-LER increases after the ingestion of a highfat meal. Lercanidipine is highly bound to plasma protein (>98%) in humans. Its volume of distribution of 2–2.5 L/kg was determined in healthy volunteers after intravenous infusion of 2 mg. Lercanidipine is extensively metabolized by CYP 3A4 to inactive pyridine derivatives. A crossover study involving a single administration of either 10 mg of (R)- or (S)-LER or 20 mg of rac-LER as a solution demonstrated no in vivo enantiomer interconversion

Levlofexidine is R-enantiomer of a α2A adrenergic receptor agonist Lofexidine. Levlofexidine (as a component of Lofexidine) can be used as a short-acting anti-hypertensive but is mostly used to help relieve symptoms of heroin or opiate withdrawal in opiate dependency. Lofexidine is approved in the United Kingdom but is still undergoing clinical trials in the United States. Levlofexidine showed an approximately 9-fold higher affinity than Dexlofexidine for the alpha 2-adrenoceptor-like binding sites in rat brain membranes identified by [3H]-clonidine and was 4 times more potent at displacing [3H]-prazosin from alpha 1-adrenoceptors. The possibility of using lofexidine to treat alcohol addiction withdrawal symptoms has been investigated and has not yet been shown to be an effective treatment.

Mitoguazone is a guanylhydrazone derivative with potential antineoplastic activity. Mitoguazone inhibits S-adenosyl-L-methionine decarboxylase (SAMD), an enzyme involved in the synthesis of polyamines, resulting in a decreased proliferation of tumor cells, antimitochondrial effects, and p53-independent apoptosis. In the 1960s the drug was investigated in clinical trials. Despite the responses in acute leukemia, chronic myelogenous leukemia, lymphoma, multiple myeloma, head and neck cancer, esophageal cancer and other types of cancer, the development of the drug was discontinued because of marked myelosuppression and mucositis. Using a weekly schedule of administration, mitoguazone had minimal toxicity and showed limited activity in patients with lymphoma, esophageal cancer, prostate cancer, and other types of tumors.

Aminopropyl racementhyl phosphate is a prodrug of menthol patented by Pacific Corporation (Korea). Upon administration, it is enzymatically decomposed into menthol and 3-aminopropylphosphoric acid, a component used for anti-aging cosmetic composition. Aminopropyl racementhyl phosphate was found to reduce the irritation of menthol while maintaining its useful effects.

LB80380 is a prodrug of besifovir, a novel antiviral agent for the treatment of chronic hepatitis B.

Carazolol is a beta1/beta2 adrenoreceptor blocking agent. Activity and safety of the drug were evaluated in clinical trials that were conducted in healthy subjects and in patients suffering from either chronic bronchitis or asthma. The drug, however, was not developed for human use. Instead, carazolol is used in to reduce stress in animals during transportation. In veterinary medicine, carazolol is given by intramuscular injection to pigs is indicated in stress-inducing situations. In cattle, carazolol is intended to be used for the prevention of shipment stress caused by transportation and formation of new herds.

Homochlorcyclizine (INN) is an antihistamine which has been marketed in Japan since 1965. It is used in the treatment of Itching sensation resulting from skin diseases (eczema or dermatitis, pruritus, drug eruption, toxic erythema and infant strophulus), urticaria and allergic rhinitis. Homochlorcyclizine hydrochloride possesses several pharmacological properties: 1) inhibits bradykinin-induced contractions of isolated guinea pig ileum; 2)partially blocks SRS-A (slow-reacting substance of anaphylaxis )- induced contractions in isolated guinea pig il eum. 3) Homochlorcyclizine hydrochloride completely inhibits histamine-induced contractions at a concentration of 0.1μg/mL, while it completely inhibits serotonin or acetylcholine- induced contractions at a concentration of 1μg/mL.

KETAZOLAM, a benzodiazepine with an additional d-face-fused heterocyclic ring, possesses anxiolytic, anticonvulsant, sedative and skeletal muscle relaxant properties. It is used for the treatment of anxiety and spasticity.

Butetamate is a cough suppressant. It exerts antispasmodic, bronchodilator and anticholinergic properties.

Magnesium isoglycyrrhizinate is a magnesium salt form of isoglycyrrhizinate, a derivative of glycyrrhizic acid extracted from the roots of the plant Glycyrrhiza glabra. Magnesium isoglycyrrhizinate has anti-inflammatory, antioxidant and hepatoprotective activities. The drug is believed to be a free radical scavenger and to modulate the activity of hepatic enzymes. Magnesium isoglycyrrhizinate was investigated in clinical trials to restore hepatic impairments caused by chemotherapy drugs and as a treatment of chronic liver diseases.