Coumazoline is a vasoconstrictor developed as a nasal decongestant by a French corporation Labez. Intravenous administration of the compound to dogs lead to a marked and prolonged drop in the temperature of the gingival mucosa. In rats, coumazoline caused slowing of the dye diffusion on the surface of the skin. The compound did not influence the ciliary motility, as was measured on an isolated guinea pig trachea.

Dexlofexidine is an isomer “+“ of lofexidine, which is agonist of alpha 2-adrenoceptor, but in 10 times less potent than the other isomer, levlofexidine.

Esproquine is a tetrahydroisoquinoline derivative. It exerts positive inotropic effect and increases arterial pressure.

Deriglidole was reported to inhibit alpha 2-adrenoceptors and ATP-sensitive K+ channels in mouse pancreatic B-cells, and to increase insulin release. The effects of deriglidole are stereoselective on alpha 2-adrenoceptors, but not on ATP-sensitive K+ channels of pancreatic B-cells. Deriglidole had been in phase II clinical trial for the treatment of diabetes mellitus type II in France. However, the study was discontinued.

Domazoline is anticholinergic agent. It is antazoline derivative. Domazoline is antihistaminic, local vasoconstrictor and nasal decongestant. As a hair stiffener, it was used in depilatory preparations.

Upidosin [REC 152739, REC 22009] is an α1-blocker that was in phase II trials with Recordati in Belgium and Israel for the treatment of benign prostatic hyperplasia. When evaluated in radioligand binding assays with expressed animal or human alpha-1 ARs, Upidosin shows marked to moderate selectivity for the alpha-1a AR subtype. Its affinity for the recombinant alpha-2 AR subtypes or native dopaminergic D2 receptor was about 100-fold lower than that for alpha-1a AR subtype.

Tropodifene (Tropaphen) is an α-Adrenergic receptor blocking agent. Clinical trials have shown that tropaphen has a beneficial effect on hypertension. Tropaphen has a very marked adrenolytic and vasodilator action. It greatly lowers the tone of the peripheral vessels. The preparation is effective starting with a dose of 0.1 mg/kg. After injection of the drug in a dose of 0.25 mg/kg, a considerable and gradually progressive decrease in the perfusion pressure takes place. The pressure falls by 30-35% and remained at a low level for 90-100 min. With a dose of tropaphen of 0.5 mg/kg, the perfusion pressure falls by 40-45% and remains low for 120 min or more. Strong vasodilatation is also observed after injection of tropaphen into intact rabbits.

Turosteride [FCE 26073] is a selective 5α-reductase inhibitor being developed by Pharmacia Corporation. Turosteride inhibits human and rat prostatic 5 alpha-reductases with IC50 values of 55 and 53 nM, respectively. It was in phase II clinical trials in Italy for the treatment of benign prostatic hyperplasia.

Flutonidine, an alpha2-adrenergic receptor agonist was studied as an antihypertensive drug. However, information about the current use of this drug is not available.

Tibalosin is a phenylethylamine derivative patented by Continental Pharma as a potent vasodilator. Tibalosine interacts specifically with alpha- and beta-adrenergic receptors and calcium channel binding sites. In preclinical models, Tibalosin exerts favor influences on arterial pressure in the hypertensive animal. The drug has acceptable toxicity in experimental animals and has been well tolerated by normal human subjects in daily doses of up to 200 mg.