Ofornine is a vasodilator with antihypertensive activity. Experiments on rats have shown that ofornine reduced spontaneously hypertensive (SH) blood pressure through vasodilating and presynaptic adrenolytic activities, and that a dopaminergic mechanism may be involved. Information about the current use of this drug is not available.

Barucainide, an IB anti-arrhythmic agent, was evaluated in patients with coronary artery disease. Its antiarrhythmic effect was studied in patients with markedly depressed left-ventricular function. Barucainide was in phase II clinical trials to treat the patients with arrhythmias but the development of the drug was discontinued.

Terikalant is a benzopyran derivative patented by Rhone-Poulenc Sante as an antiarrhythmic agent. In normal cardiac tissues studied in vitro, Terikalant dose-dependently prolonged the atrial and ventricular action potential but affected neither the upstroke of the action potential nor the diastolic potential. Patch-clamp experiments demonstrated that the prolongation of the action potential induced by Terikalant is due to a specific blockade of the inward rectifier K+ current. In vivo, i.v. administration to anesthetized dogs of low doses of Terikalant consistently induced bradycardia and prolonged the atrial, nodal, and ventricular refractory periods, but did not affect the conduction velocity.

Sulrnazole (the former AR-L 115 BS) is a benzimidazole derivative with positive inotropic, positive chronotropic and vasodilator effects. Sulrnazole also has been shown to improve cardiac index and reduce pulmonary capillary wedge pressure without significant change in heart rate or arterial pressure. Intravenous administration caused a 217 per cent increase in cardiac output with a 25 per cent decrease in pulmonary wedge pressure. Short-term oral administration resulted in a 317 per cent increase in cardiac index and a 317 per cent increase in ejection fraction. Side effects have included visual blurring and transient colour blindness. Sulmazol has been demonstrated to improve regional wall motion in patients with ischemic heart disease and to abolish pacing-induced ischemia. Sulrnazole is an A1 adenosine receptor antagonist. It is also a phosphodiesterase inhibitor.

Lificiguat (YC-1) [3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole], a chemically synthetic benzylindazole compound, is a direct soluble guanylate cyclase activator. It possessed antiplatelet activity. YC-1 inhibits Hypoxia-inducible factor-1 (HIF-1). YC-1 demonstrated antineoplastic potential both in vitro and in vivo in animal models.

Ronipamil was developed as a verapamil analogue with a longer duration of action. However, it has much less calcium antagonist action than verapamil. Ronipamil has been tested for its ability to reduce ischaemia-induced arrhythmias in conscious rats. Compared to similar compounds, ronipamil was less effective and produced no statistically significant antiarrhythmic effects in rats. It had limited haemodynamic effects and no marked actions on blood pressure and heart rate. In another study, ronipamil prolonged survival time after traumatic shock and was shown to possess anti-shock potential. No information on current development of this drug is available.

Piridoxilate is a conjugation product of pyridoxine and glyoxylic acid in which pyridoxine is supposed to facilitate in vivo transformation of glyoxylic acid to glycine rather than to oxalic acid. The protective action of piridoxilate against hypoxia and metabolic inhibition of the myocardium was confirmed in the experiments on the canine heart-lung preparation using the redox potential of the myocardium and the pyridine nucleotide fluorescence of the heart as indices of cellular energy metabolism. The protective action of piridoxilate against hypoxia which may be attributable to rearrangement of the myocardial metabolism. Piridoxilate did not induce any significant changes in objective and subjective sleep variables. Long-term treatment with piridoxilate may result in overproduction of oxalic acid and in calcium oxalate nephrolithiasis. Piridoxilate should be added to the list of chemicals responsible for chronic oxalate nephropathy.

Carocainide is a benzofuran derivative patented by pharmaceutical company Delalande S. A. For treatment cardiovascular disease. Carocainide showing antiarrhythmic properties in animal models. In isolated papillary muscles and Purkinje fibers it decreases the maximum rate of rise of the action potential and in Purkinje fibers it decreases the plateau amplitude and the duration of the action potential. Carocainide increases the ratio of the effective refractory period to the action potential duration at 90% of repolarization, shifts the membrane responsiveness curve towards more negative membrane potentials and slows down the recovery of the maximum rate of rise of the action potentials of the Purkinje fibers. Carocainide also increases the conduction time at the Purkinje papillary muscle junction.

Taprizosin (also known as UK-338,003) is an alpha1A-adrenoceptor antagonist that was developed for the treatment of benign prostatic hyperplasia. However, this compound possesses poor oral absorption.