Product name: 3-epi-Bufalin
Synonym name: 3a-Hydroxybufalin
Catalogue No.: BP5040
Cas No.: 465-20-3
Formula: C₂₄H₃₄O₄
Mol Weight: 386.532
Botanical Source:
Type of Compound: Steroids

Purity: 95%~99%
Analysis Method: HPLC-DAD or/and HPLC-ELSD
Identification Method: Mass, NMR
Packing: Brown vial or HDPE plastic bottle

Storage: Store in a well closed container, protected from air and light. Put into refrigerate or freeze for long term storage.
Whenever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20℃. Generally, these will be useable for up to two weeks.

The product could be supplied from milligrams to grams
Inquire for bulk scale.

For Reference Standard and R&D, Not for Human Use Directly.

Storage conditions：Short-term storage at 2~8℃, long-term storage at -20 ~ -80℃

Introduction/Overview

3-epi-bufalin (CAS No.: 465-20-3) is an important natural product of the toad dienolactone family, belonging to the toadin family derivative. This compound is obtained by microbial conversion of toadsionolide, featuring a unique three-dimensional configuration and biological activity. Toadsoxins have long attracted attention in cardiovascular disease treatment due to their significant cardiotonic effects and multi-target regulatory functions. 3-Biaochan Duling, as an isomer of toadoxin, exhibits pharmacological properties and safety advantages distinct from the parent compound, making it a hot topic in natural product pharmacology research.

This paper systematically reviews the chemical structure and physicochemical properties, sources and extraction methods, pharmacological activity and mechanism of action of 3-Biaochan Duling, druggability evaluation, and pharmacokinetic characteristics, and explores its clinical application prospects and future development directions, aiming to provide scientific basis and reference for in-depth research and drug development of this natural product.

Chemical structure and physicochemical properties

3-Epitoad Toxic is a stereoisomer of toadsionolide compounds, with a molecular formula of C24H34O4 and a molecular weight of 386.5320. Its structural core is a typical steroid skeleton, containing characteristic dienolactone rings. The hydroxyl group configuration at the 3-position carbon atom is epitope, while the hydroxyl group at the 3-position differs from the parent Bufalin atom by having an axial (α) configuration.

In terms of physicochemical properties, the LogP value of 3-Biepitochan Venoming is 3.4670, showing moderate lipid solubility, which is beneficial for cell membrane penetration and distribution in vivo. Its topological pole surface area (TPSA) is 70.67 Ų, indicating that the molecule has certain polarity, which helps form non-covalent hydrogen bonds with biological targets. Low water solubility (0.0068 mg/mL) suggests limited solubility in the aqueous phase, which may affect its bioavailability. High blood-brain barrier permeability indicates that this compound can enter the central nervous system and has potential central functions. Importantly, 3-Epitochan Doxin showed no hERG channel inhibitory activity, and the Ames mutagenic test was negative, indicating good safety and reduced risk of arrhythmias and genotoxicity.

Plant Origins and Extraction Methods

3-Epitoxin is not a natural product extracted directly from plants, but is obtained through microbial transformation of toad dienolactone. Toad dienolactone is mainly found in toad skin secretions, especially in the Chinese toad (Bufo bufo gargarizans) and related toad species. Traditionally, toxin compounds are obtained by extracting and separating organic solvents from toad skin secretions.

Microbial transformation technology provides an efficient and environmentally friendly method for the preparation of 3-epitoad toxin. By screening specific microbial strains (such as certain Streptomycetes or actinomycetes), their unique enzyme systems are used to stereoselectively isomerize toad dienolactones, forming a three-position hydroxy-epitope isomer. This method not only improves yield and purity but also avoids complex chemical synthesis steps, aligning with green chemistry principles.

The extraction process generally includes: organic solvent extraction of toad skin secretions (such as methanol or ethanol), enrichment of toad dienolactone through liquid-liquid separation and column chromatography, followed by microbial transformation reactions, and finally purification by high-performance liquid chromatography (HPLC) to obtain 3-epitoxin.

Pharmacological activity research

The pharmacological activity of 3-Biaochan Duling is mainly concentrated in the cardiac strengthening effect. Multiple in vitro and in vivo studies have shown that this compound can significantly enhance myocardial contractility and improve heart function, offering potential value in heart failure treatment.

Cardiac strengthening

3-Epiopan Venom enhances myocardial contractility by regulating calcium ion homeostasis within myocardial cells. Its mechanism involves multiple ion channels and membrane proteins, including:

• CACNA1C (L-type calcium channel α1C subunit): promotes calcium ion influx and enhances myocardial contraction.
• ATP1A1/A2/A3 (Na⁺/K⁺-ATPase α subunit): Inhibits Na⁺/K⁺ pump activity, leading to increased intracellular Na⁺ concentration, indirectly promoting reverse function of the Na⁺/Ca²⁺ exchanger (SLC8A1), increasing intracellular Ca²⁺.
• SLC8A1 (Sodium-Calcium Exchanger): Regulates intracellular calcium ion concentration, participating in myocardial contraction regulation.
• KCNJ2 (Internal Rectifying Potassium Channel): Regulates the resting membrane potential of myocardial cells, affecting heart rate and electrical activity stability.
• RYR2 (intracellular plasmic reticulum calcium release channel): regulates calcium ion release and participates in the myocardial contraction cycle.
• ATP1B1/B3 (Na⁺/K⁺-ATPase β subunit): Regulates pump stability and function.

Through the synergistic effects of these targets, 3-Bioptoad Venom can effectively enhance myocardial contractility while maintaining electrophysiological stability and reducing the risk of arrhythmias.

Other pharmacological effects

In addition to its cardiotonic effect, preliminary studies have also found that 3-epitochan toxin may have anti-tumor, anti-inflammatory, and neuroprotective activities, but the related mechanisms are not yet fully elucidated and require further systematic study.

Mechanism of action and molecular targets

The mechanism of action of 3-Biaochan Duling is mainly based on its high affinity for Na⁺/K⁺-ATPase on cell membranes, inhibiting its activity and leading to increased intracellular Na⁺ concentration. Changes in Na⁺ concentration affect the functioning of the sodium-calcium exchanger (SLC8A1), promoting Ca²⁺ influx, increasing calcium ion concentration within myocardial cells, and thereby enhancing myocardial contractility.

Additionally, 3-Epitochan Venol also regulates the L-type calcium channels (CACNA1C) and calcium release channels (RYR2) within myocardial cells, synergistically promoting calcium signaling. Regulating potassium channels (KCNJ2) helps maintain electrophysiological stability in myocardial cells and reduces the occurrence of arrhythmias.

Molecular docking and kinetic simulations showed that the binding pattern of 3-epitochan toxin to Na⁺/K⁺-ATPase was similar to that of toadolin, but due to changes in the three-position hydroxyl stereotype, the binding affinity and kinetic properties differed, possibly explaining its lower hERG channel inhibitory activity and better safety.

Druggability evaluation and pharmacokinetics

The druggability parameters of 3-Biaochan Duling indicate that it has good potential for drug development:

• The molecular weight (386.5320) complies with the Lipinski rule, which is beneficial for oral absorption.
• LogP (3.4670) is moderate, balancing lipid solubility and water solubility, which is beneficial for distribution in the body.
• TPSA (70.67 Ų) is moderate, supporting good cell membrane penetration.
• Water solubility (0.0068 mg/mL) was relatively low, suggesting the need for formulation optimization to improve bioavailability.
• High blood-brain barrier permeability suggests potential central nervous system involvement, but central toxicity risk should also be considered.
• hERG suppression is negative, reducing the risk of arrhythmias.
• The Ames test was negative, indicating no significant genotoxicity.

Pharmacokinetics, 3-epitoad toxin is well absorbed orally with a moderate half-life, mainly metabolized by the liver, and the metabolites are safe. Its high blood-brain barrier permeability offers potential therapeutic possibilities for central nervous system diseases, but caution is also needed regarding central nervous system toxicity and drug interactions.

Prospects and outlooks for clinical applications

3-Biaochan Venoling, as a naturally derived cardiotonic drug candidate molecule, has significant pharmacological activity and good safety profile, and holds broad application prospects in the future in the treatment of cardiovascular diseases such as heart failure and arrhythmias. Its high blood-brain barrier permeability may also expand into research areas of central nervous system diseases.

Future research should focus on:

• Systematic review of pharmacodynamics and toxicology: clarify its effective dose range and long-term safety.
• Pharmacokinetic optimization: Enhancing water solubility and bioavailability through structural modification or formulation technologies.
• In-depth analysis of the mechanism of action: Combining multi-omics technology, revealing its multi-target collaborative regulatory network.
• Preclinical and clinical research: Conduct animal models and early clinical trials to verify therapeutic efficacy and safety.
• Derivatives development: Based on the structure of 3-epitoad venoming, design novel cardiotonic molecules to improve selectivity and efficacy.

In summary, 3-Biotochan Venoling, as an innovative representative of toxin drugs, combines the diversity of natural products with the needs of modern drug development, and has the potential to become a new generation of cardiac stimulants.

Conclusion

3-Epitochan Venolin, as a microbial transformation product of toad dienolactone, demonstrates significant value in the field of natural product pharmacology due to its unique chemical structure and significant cardiotonic activity. Its multi-target mechanism of action and favorable druggability parameters provide new ideas and candidate molecules for the treatment of cardiovascular diseases. In the future, through in-depth pharmacological mechanism research, pharmacokinetic optimization, and clinical validation, 3-Biaochan Duling is expected to become an effective cardiotonic drug for clinical use, offering new treatment options for cardiovascular disease patients.

With continuous advances in natural product research technology, research on 3-Biaochan Duling will further promote the integration of natural product pharmacology with modern drug development, facilitate the discovery and application of innovative drugs, and support the advancement of human health.