Truxipicurium, a derivative of alpha-truxillic acid, a curare-like drug, is a neuromuscular blocking agent with rigid structure.

Modaline is piperidinopyrazine derivative developed by Warner-Lambert Pharmaceutical Co. as Antidepressant. Modaline is a potent monoamine oxidase (MAO) inhibitor of the order of the more effective hydrazines. Pretreatment with harmaline, a reversible MAO inhibitor, or with serotonin prevented the irreversible inhibition by Modaline, suggesting that Modaline (as an active MAO inhibitor) occupies the same site on MAO as harmaline, the hydrazines, or serotonin. Modaline differs from the monoamine oxidase inhibitors by producing an increase in body temperature in fully reserpinized animals. Modaline differs from imipramine‐like drugs in not potentiating the hyperthermic effect of isoprenaline.

Coumermycin is from the aminocoumarin class of antibiotic compounds which acts by inhibiting DNA gyrase. Coumermycin is effective against gram-positive bacteria, but not gram-negative bacteria. Coumermycin its derivatives have been studied since the 1950's as potential antibiotic. However, it has seen little to no clinical development because of its low water solubility, toxicity profile, and ineffectiveness against gram-negative bacteria.

Piquizil, a 4-aminoquinazoline causing relaxation of respiratory smooth muscle in animals, appeared to be a bronchodilator in man. It has been shown to be equal in activity to a combination of theophylline, ephedrine and phenobarbital. Piquizil and Tedral were equally effective in the management of asthmatic patients.

Levisoprenaline (l-isoproterenol) is beta1- and beta2-adrenoreceptor agonist. In Japan, continuous inhalation of levisoprenaline is a recommended treatment for pediatric patients with acute severe exacerbation. Compared with salbutamol, l-isoproterenol reduced modified pulmonary index score more rapidly. But in most countries do not recommend continuous inhalation of l-isoproterenol to treat pediatric patients with acute severe exacerbation of asthma due to worsening asthma control. Levisoprenaline was used to cause experimental chronic heart failure in rats.

Levosemotiadil is an S-enantiomer of semotiadil. It is an antiarrhythmic drug with sodium and calcium channel blocking action, as well as potassium blocking activity. Levosemotiadil is bound strongly and enantioselectively to human serum albumin and human alpha1-acid glycoprotein. Since levosemotiadil is hydrophobic basic drug, it is likely that this drug is also bound to lipoprotein in human plasma. Levosemotiadil might be effective in prevention of lethal arrhythmias. It was shown, that levosemotiadil prevented ventricular fibrillation in 64% of the high-risk animals. Heart rate responses to myocardial ischemia and to graded doses of isoproterenol were blunted by the high dose of levosemotiadil. Levosemotiadil had been in phase II clinical trials by Santen Pharmaceutical for the treatment of arrhythmias. However, this study was discontinued.

Lanperisone (NK433) is muscle relaxant. It acts by blocking voltage-gated sodium channels.

Iganidipin is a new dihydropiridynic derivative of calcium antagonist. It is the only currently available calcium antagonist in the form of ophthalmic solution. Its topical administration increases ipsilateral optic nerve head blood flow in rabbits and monkeys and inhibits the contraction of blood vessels induced by endothelin -1. Iganidipin is also used for treat Angina pectoris and Hypertension.

Clentiazem is a chloride derivative of diltiazem, originated in Tanabe Seiyaku. It works as a blocker of calcium channels. The drug was investigated in the clinical trials for the treatment of stable angina, and essential hypertension. Despite the positive results of clinical trials, no development of the drug was reported.

Tifurac is a benzofuranacetic acid derivative patented by Syntex, Inc. as an analgesic, anti-inflammatory, and antipyretic agent. In preclinical models, Tifurac can exert anti-inflammatory and analgesic activity in rat paw edema assay and mouse writhing assay.