Dihydroergocristine is a semi‑synthetic ergot alkaloid belonging to the lysergic acid family of compounds. It is the hydrogenated analogue of ergocristine and is derived from ergot alkaloids produced by the fungus Claviceps purpurea.
Chemical identity
- IUPAC name: Not universally agreed; reported variants include [(6aR,9R,10aS)-6,6‑dimethyl‑9‑(2‑hydroxy‑2‑methylpropyl)‑10‑prop‑1‑enyl‑6a,9‑dihydro‑5H‑indolo$$
2,3‑a]pyrrolo[2,1‑c]isoquinoline‑2‑carboxylic acid]. - Molecular formula: C₃₃H₄₁N₅O₅ (reported).
- Molecular weight: Approximately 603 g·mol⁻¹.
- CAS Registry Number: 64741‑44‑2 (as listed in some chemical databases).
- Structural class: Ergot alkaloid; downstream of lysergic acid derivatives.
Natural occurrence and production
Dihydroergocristine is not found in significant quantities in nature; it is typically obtained by catalytic hydrogenation of the naturally occurring alkaloid ergocristine isolated from ergot‑containing grains (e.g., rye) infected with Claviceps species. Commercial preparations of ergot extracts may contain dihydroergocristine as one component of a mixture of related alkaloids.
Pharmacology and biological activity
Ergot alkaloids, including dihydroergocristine, act as agonists or antagonists at various serotonergic, dopaminergic, and adrenergic receptors. Reported pharmacological actions of dihydroergocristine include:
- Vasodilation: Partial relaxation of vascular smooth muscle, contributing to reduced peripheral resistance.
- Uterine effects: Low‑dose uterine relaxation, contrasted with the contractile activity of some other ergot alkaloids.
- Central nervous system activity: Interaction with serotonergic pathways, though its potency is considerably lower than that of more widely used ergot derivatives such as ergotamine or dihydroergotamine.
Clinical investigations in the mid‑20th century examined dihydroergocristine for the treatment of peripheral vascular disorders and migraine prophylaxis. However, comparative studies demonstrated limited efficacy relative to other ergot derivatives, and its use declined with the advent of more selective agents.
Medical and veterinary use
Historically, dihydroergocristine was included in some poly‑alkaloid formulations employed for:
- Management of peripheral circulatory insufficiency (e.g., Raynaud’s phenomenon).
- Adjunctive therapy for migraine (as part of mixed ergot alkaloid preparations).
Current pharmacopeias and regulatory compendia do not list dihydroergocristine as an independently marketed drug in major jurisdictions (e.g., United States, European Union). Its presence today is largely confined to research contexts or as a minor constituent of traditional ergot extracts.
Toxicology
As with other ergot alkaloids, dihydroergocristine can produce vasoconstrictive or vasodilatory side effects depending on dose and receptor affinity. Overdose may lead to symptoms such as nausea, vomiting, hypertension or hypotension, and peripheral ischemia. Chronic exposure to ergot alkaloids is associated with ergotism, a condition characterized by vasospasm, gangrene, and convulsive disturbances. Specific toxicological data for dihydroergocristine are limited, and safety assessments rely on the broader class profile of ergot alkaloids.
Legal and regulatory status
- United States: Not scheduled under the Controlled Substances Act; however, ergot alkaloid preparations are regulated as prescription drugs.
- European Union: Subject to the European Medicines Agency (EMA) regulations governing herbal or botanical medicinal products containing ergot alkaloids.
Research significance
Dihydroergocristine serves as a molecular probe in studies of receptor binding, particularly for elucidating structure‑activity relationships among lysergic acid derivatives. Its relatively modest activity compared with other ergot alkaloids makes it useful for distinguishing receptor subtype selectivity in pharmacological assays.
References
(References would be listed here in a formal encyclopedic entry, drawing from peer‑reviewed journals, pharmacopeial monographs, and authoritative chemical databases such as PubChem, ChemSpider, and the Merck Index.)