Ergonovine maleate
[CAS# 129-51-1]

Identification

• Classification: API >> Hormone and endocrine-regulating drugs >> Pituitary hormone
• Name: Ergonovine maleate
• Synonyms: Ergometrine hydrogen maleate
• Molecular Formula: C₁₉H₂₃N₃O₂.C₄H₄O₄
• Molecular Weight: 441.48
• CAS Registry Number: 129-51-1
• EC Number: 204-953-5
• SMILES: C[C@@H](CO)NC(=O)[C@H]1CN([C@@H]2CC3=CNC4=CC=CC(=C34)C2=C1)C.C(=CC(=O)O)C(=O)O

Properties

• Melting point: 200 °C (Expl.)

Safety Data

• Hazard Symbols: GHS06 Danger
• Risk Statements: H301-H311-H331
• Safety Statements: P261-P262-P264-P270-P271-P280-P301+P316-P302+P352-P304+P340-P316-P321-P330-P361+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	3	H301
Acute toxicity	Acute Tox.	3	H311
Acute toxicity	Acute Tox.	3	H331
Acute toxicity	Acute Tox.	4	H302
Reproductive toxicity	Repr.	2	H361
Acute toxicity	Acute Tox.	4	H332
Skin sensitization	Skin Sens.	1	H317
Skin irritation	Skin Irrit.	2	H315

Discovery and Applications

Ergonovine maleate is the maleate salt form of ergonovine, an ergot alkaloid derived from *Claviceps purpurea*, a fungus that grows on rye and related plants. The compound is structurally classified as a lysergic acid derivative and has the molecular formula C₁₉H₂₃N₃O₂·C₄H₄O₄. It consists of a tetracyclic ergoline skeleton with a methylaminopropanol side chain at the C-8 position, and it forms a stable salt with maleic acid, enhancing its water solubility and stability.

Ergonovine was first isolated in the early 20th century as one of several bioactive compounds from ergot fungi. It was identified as a potent uterotonic agent due to its ability to induce contractions of uterine smooth muscle. Ergonovine maleate was subsequently developed as a pharmaceutical for obstetric use, particularly in the prevention and treatment of postpartum hemorrhage.

The compound acts primarily on α-adrenergic, serotonin (5-HT₂), and dopamine receptors in smooth muscle, especially in the uterus. Its pharmacological effect includes sustained uterine contraction, which can aid in reducing bleeding following childbirth or abortion. Compared to other ergot alkaloids, ergonovine is relatively selective for uterine tissue and exhibits less vasoconstrictive activity, although it may still pose cardiovascular risks in certain patients.

Ergonovine maleate has also been used diagnostically in cardiology. It was once employed in the provocation of coronary artery spasm in patients suspected of having variant (Prinzmetal’s) angina, under controlled conditions during angiography. This use, however, has declined due to safety concerns and the availability of alternative agents.

The pharmaceutical formulation of ergonovine maleate is typically administered orally or by injection. The salt form improves its solubility in aqueous media, making it suitable for clinical use. Dosage and administration require careful control, as excessive doses can lead to hypertension, vasospasm, and other adverse effects. Contraindications include pregnancy (except during labor), cardiovascular disease, and sepsis.

Chemically, ergonovine maleate is a crystalline solid, soluble in water and alcohol. It is sensitive to light and heat and should be stored in airtight, light-resistant containers. The maleate counterion is derived from maleic acid and contributes to the compound’s pharmaceutical properties without direct pharmacological activity.

Structurally, the ergoline ring system is shared with other biologically active compounds, including LSD and bromocriptine, which also act on serotonin and dopamine receptors. The hydroxyl and amine functionalities on the side chain of ergonovine make it amenable to further chemical derivatization, though its primary medical use remains in its native salt form.

In summary, ergonovine maleate is a clinically important ergot alkaloid salt used historically and currently in obstetrics to control uterine bleeding. Its biological activity stems from its ergoline structure and receptor interactions, and its maleate salt form enhances pharmaceutical handling and bioavailability.

References

2001. Hydrolysis of lysergamide to lysergic acid by Rhodococcus equi A4. Journal of Biotechnology, 84(1).
DOI: 10.1016/s0168-1656(00)00332-1

1998. Randomized comparison of rectal misoprostol with Syntometrine for management of third stage of labor. Acta Obstetricia et Gynecologica Scandinavica, 77(2).
DOI: 10.1034/j.1600-0412.1998.770209.x

1979. Effect of ergometrine on contractile force of guinea-pig isolated heart: Antagonism by cimetidine. Inflammation Research, 10(4).
DOI: 10.1007/bf02024090