Pirenzepine

Structural formula
General
Non-proprietary name	Pirenzepine
other names	11 - [(4-Methylpiperazin-1-yl) acetyl] 6,11-dihydro-5 H -pyrido [2,3- b ] [1,4] benzodiazepin-6-one ( IUPAC ) Pirenzepinum ( Latin )
Molecular formula	C 19 H 21 N 5 O 2
External identifiers / databases
CAS number 28797-61-7 (pirenzepine) 29868-97-1 (pirenzepine di hydrochloride ) 84827-28-1 (pirenzepine dihydrochloride monohydrate) PubChem 4848 DrugBank DB00670 Wikidata Q419550
Drug information
ATC code	A02 BX03
Drug class	Ulcer therapeutic agent
Mechanism of action	Muscarinic acetylcholine receptor - inhibitor
properties
Molar mass	351,40 g · mol -1
Melting point	226-228 ° C 250–252 ° C (dihydrochloride monohydrate)
safety instructions
Please note the exemption from the labeling requirement for drugs, medical devices, cosmetics, food and animal feed GHS labeling of hazardous substances no GHS pictograms H and P phrases H: no H-phrases P: no P-phrases
Toxicological data	427 mg kg −1 ( LD 50 ,  mouse ,  ip ) 156 mg kg −1 ( LD 50 ,  mouse ,  iv ) 3046 mg kg −1 ( LD 50 ,  mouse ,  oral ) 96 mg kg −1 ( LD 50 ,  mouse ,  iv ) (dihydrochloride) 2600 mg kg −1 ( LD 50 ,  mouse ,  oral ) (dihydrochloride) 92 mg kg −1 ( LD 50 ,  rat ,  iv ) (dihydrochloride) 5000 mg kg −1 ( LD 50 ,  rat ,  oral ) (dihydrochloride) 62.5 mg kg −1 ( LD 50 ,  dog ,  iv ) (dihydrochloride) > 3700 mg kg −1 ( LD 50 ,  dog ,  oral ) (dihydrochloride)
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Pirenzepine ( trade name : Gastrozepin ^® , manufacturer: Boehringer Ingelheim ), a substance from the group of parasympatholytics , selectively inhibits muscarinic acetylcholine receptors and has a particularly high affinity for M ₁ acetylcholine receptors .

Pirenzepine is used to reduce gastric acid secretion, because by inhibiting the M.-Receptors of enterochromaffin-like cells less histamine is secreted and thus gastric acid secretion is reduced.

At the usual dose of 100–150 mg / day for treatment, pirenzepine also inhibits the M ₃ receptors on the parietal cell , with typical anticholinergic effects such as dry mouth and tachycardia, which is why it no longer plays a role in ulcer therapy.

The treatment of myopia with pirenzepine is currently being investigated.

Manufacturing

Pirenzepine is synthesized in five steps. In the first step, the corresponding benzoic acid amide is formed from 2-chloro-3-aminopyridine and 2-nitrobenzoyl chloride . Thereafter in the presence of Raney nickel , the hydrogenation of the nitro function to the amine. The ring closure to give 5,11-dihydro-6 H -pyrido [2,3- b ] [1,4] benzodiazepin-6-one is performed in the third step at 200 ° C. The side chain is then introduced by reaction with chloroacetyl chloride . In the last step, the target compound is obtained by a substitution reaction with 1-methylpiperazine .

Trade names

Gastricur (D), Gastrozepin (D), Ulcoprotect (D)

Individual evidence

1. ↑ Patent ZA695933DE1795183 (Thomae 1969).
2. ↑ Entry on pirenzepine. In: Römpp Online . Georg Thieme Verlag, accessed on January 25, 2015.
3. ↑ Data sheet Pirenzepine dihydrochloride from Sigma-Aldrich , accessed on June 16, 2011 ( PDF ).
4. ↑ Entry on pirenzepine in the ChemIDplus database of the United States National Library of Medicine (NLM) .
5. ↑ ^{a b c d e f g h i} Axel Kleemann , Jürgen Engel, Bernd Kutscher, Dietmar Reichert: Pharmaceutical Substances. 4th edition. 2 volumes published by Thieme-Verlag, Stuttgart 2000, ISBN 1-58890-031-2 ; online since 2003 with biannual additions and updates.
6. ↑ K. Aktories, U. Förstermann, F. Hofmann, W. Forth: General and special pharmacology and toxicology. 9th edition. Urban & Fischer at Elsevier, 2005, ISBN 3-437-42521-8 .
7. ↑ D. Czepita: Fundamentals of modern treatment of myopia . In: Ann Acad Med Stetin . tape 51 , no. 2 , 2005, p. 5-9 , PMID 16519089 .
8. ↑ "Miracle Gel" stops myopia in children. ( Memento of the original from December 7, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. on: netdoktor.at , January 9, 2003, accessed January 30, 2013. 
9. ↑ Help for the nearsighted? on: tagesspiegel.de , November 19, 2008, accessed January 30, 2013.

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !