Pipazetate () (brand names Dipect, Lenopect, Selvigon, Theratuss, Toraxan), or pipazethate (), is a pyridobenzthiazine

cough suppressant Cold medicines are a group of medicinal, medications taken individually or in Combination drug, combination as a Symptomatic treatment, treatment for the symptoms of the common cold and similar conditions of the upper respiratory tract. The t ...

, closely related to the

phenothiazine Phenothiazine, abbreviated PTZ, is an organic compound that has the formula S(C6H4)2NH and is related to the thiazine-class of heterocyclic compounds. Derivatives of phenothiazine are highly bioactive and have widespread use and rich history. T ...

class. It binds to the

sigma-1 receptor The sigma-1 receptor (σ1R), one of two sigma receptor subtypes, is a chaperone protein at the endoplasmic reticulum (ER) that modulates calcium signaling through the IP3 receptor. In humans, the σ1 receptor is encoded by the ''SIGMAR1'' gene. ...

with an IC₅₀ value of 190 nM. It also has local anesthetic action, and in large doses can produce seizures. As the brand name Theratuss, it was approved by the FDA in 1962, on evidence of safety only. It was withdrawn from the US market in 1972 when the manufacturer, E.R. Squibb, and Sons, failed to produce evidence of efficacy. Clinical studies showed that it did not decrease cough frequency at recommended dosages. Infrequent side effects include nausea, vomiting, drowsiness, fatigue, rash, and

tachycardia Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal (su ...

Synthesis

Note: 1-azaphenothiazine is also used for making

Prothipendyl Prothipendyl (brand names Dominal, Timovan, Tolnate), also known as azaphenothiazine or phrenotropin, is an anxiolytic, antiemetic, and antihistamine of the phenothiazine, azaphenothiazine group which is marketed in Europe and is used to treat anx ...

Isothipendyl Isothipendyl is a 1st generation H1 antagonist (antihistamine) and anticholinergic used as an antipruritic. It is nowadays scarcely used in the 1st line relief of allergies due to the anticholinergic side effect of somnolence but does have some ...

The reaction of 1-azaphenothiazine 61-96-1(1) with phosgene gives 1-azaphenothiazine-10-carbonyl chloride 4231-78-4(2). The reaction of this reactive intermediate with 2- -(piperidyl)ethoxythanol 603-43-8(3) gives the ester, thus completing the synthesis of ''Pipazethate'' (4).

References

Antitussives Sigma receptor ligands Pyridobenzthiazines 1-Piperidinyl compounds Carbamates Ethers Withdrawn drugs {{respiratory-system-drug-stub