Product name: Pterosin B
Synonym name: (2R)-Pterosin B
Catalogue No.: BP5047
Cas No.: 34175-96-7
Formula: C₁₄H₁₈O₂
Mol Weight: 218.296
Botanical Source:
Type of Compound:

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

Pterosin B (CAS No.: 34175-96-7) is a type of bracken derived from Pteridium aquilinum) natural indmenone compounds. As an oral active ingredient, fernin B has demonstrated multiple biological activities in recent pharmacological studies, especially showing significant potential in anti-inflammation, antioxidant, anti-myocardial hypertrophy, cognitive function improvement, and metabolic regulation. Its unique molecular structure gives fernin B excellent bioavailability and blood-brain barrier permeability, enabling it to demonstrate positive therapeutic effects in various disease models including neurodegenerative diseases, osteoarthritis, pathological cardiac hypertrophy, and diabetes.

This review aims to systematically summarize the chemical structure and physicochemical properties of fernin B, plant origins and extraction methods, with a focus on evaluating its pharmacological activity and mechanism of action, exploring its druggability and pharmacokinetic characteristics, and, combined with current research progress, anticipate its clinical application prospects, providing theoretical basis and research directions for subsequent drug development and clinical translation.

Chemical structure and physicochemical properties

Frenin B is a natural product of the inmanone class, with a molecular formula of C_13H_14O_3 and a molecular weight of 218.2960. Its structural core is the indinone skeleton, which has strong chemical stability and biological activity. The LogP value of fernin B was 2.7746, indicating moderate lipid solubility, which is beneficial for cell membrane penetration and distribution in vivo. The polar surface area (TPSA) was 37.3 Ų, indicating moderate molecular polarity, which is beneficial for oral absorption and blood-brain barrier penetration. Its low water solubility (0.0645 mg/mL) indicates limited solubility in the aqueous phase, but moderate lipid solubility aids its absorption and distribution in the body.

Notably, fern B does not exhibit hERG channel inhibitory activity, suggesting a low risk of cardiotoxicity; The Ames test result was negative, indicating a low genotoxicity risk. These physicochemical and toxicological parameters provide a solid foundation for the safety and druggability of fern B.

Plant Origins and Extraction Methods

Fern B is mainly isolated from Pteridium aquilinum. Bracken is widely distributed in temperate and subtropical regions worldwide and is a traditional medicinal and edible plant. Its above-ground parts are rich in inmanketone compounds, with fern B being relatively high.

Common extraction methods include:

1. Solvent extraction: Ethanol or methanol is used to extract dried bracken powder by reflux; the extract is concentrated and then separated and purified.
2. Liquid-liquid distribution: Use solvents of different polarities (such as ethyl acetate, n-hexane) to distribute the crude extract and enrich fern B.
3. Chromatographic separation: High-purity separation of fern B is achieved through silica gel column chromatography, reversed-phase high-performance liquid chromatography (RP-HPLC), and other technologies.

In recent years, the application of ultrasound-assisted extraction and microwave-assisted extraction technologies has improved the extraction efficiency and purity of fern B, providing technical support for large-scale preparation.

Pharmacological activity research

Research on the pharmacological activity of fern B covers multiple disease areas, mainly including anti-inflammation, antioxidant, neuroprotection, anti-myocardial hypertrophy, anti-diabetic, and anti-osteoarthritis.

1. Anti-osteoarthritis and cartilage protection

Research shows that fern B can effectively inhibit mouse chondrocyte hypertrophy and slow the progression of osteoarthritis (OA). Its mechanism involves inhibiting the expression of hypertrophy-related genes in chondrocytes, reducing the release of inflammatory mediators, protecting cartilage matrix integrity, and delaying articular cartilage degeneration.

2. Neuroprotection and improvement of cognitive function

Frenin B reduces the expression of the transcription factor Klf5 by inhibiting the Sik3 signaling pathway, thereby decreasing β-amyloid (Aβ) deposition, showing significant improvement in cognitive impairment in Alzheimer's (AD) model mice. Its excellent blood-brain barrier permeability makes it a potential candidate molecule for central nervous system drugs.

3. Anti-cardiomyocyte hypertrophy

In the pathological cardiac hypertrophy model, fern B effectively inhibits myocardial cell hypertrophy and improves heart function. This effect may be achieved by regulating intracardiac signaling pathways and inhibiting the expression of hypertrophy-related genes, suggesting its potential application value in cardiovascular disease prevention and treatment.

4. Lowers blood sugar and regulates metabolism

Frenin B has shown blood sugar-lowering effects in diabetes models and may play a role in improving insulin sensitivity and regulating signaling pathways related to glycolipid metabolism, providing new approaches for the treatment of diabetes and its complications.

5. Antibacterial activity

Frenin B exhibits certain inhibitory effects on various pathogens, with related targets including bacterial DNA gyrase (GYRA), cell membrane protein (GYPB), cell division protein (FTSZ), fatty acid synthase (FABI), and dihydrofolate reductase (DHFR). Its antibacterial spectrum covers both Gram-positive and Gram-negative bacteria, demonstrating potential anti-infective applications.

Mechanism of action and molecular targets

The multi-target mechanism of fernin B forms the basis of its broad pharmacological activity. The core mechanism mainly involves the following aspects:

1. Sik3 signaling pathway inhibition

Sik3 (salt-induced kinase 3) is an important kinase that regulates cellular metabolism and inflammatory responses. Fracken B, as an inhibitor of Sik3, regulates the expression of downstream transcription factor Klf5 by blocking its kinase activity, thereby affecting cell proliferation, differentiation, and inflammatory responses, exerting anti-inflammatory, anti-hypertrophy, and neuroprotective effects.

2. Klf5 expression regulation

Klf5 (Krüppel-like factor 5) is an important transcription factor regulating cell proliferation and fibrosis. Ferrulin B reduces cell hypertrophy and fibrosis processes by inhibiting Klf5 expression, alleviating myocardial hypertrophy and cartilage degeneration.

3. Reduced β-amyloid deposition

In Alzheimer's disease models, Fern B reduces the accumulation of β-amyloid in the brain, alleviating neurotoxicity and cognitive impairment. The specific mechanism may involve promoting Aβ clearance and inhibiting the activity of enzymes that produce related enzymes.

4. Diversification of antibacterial targets

Fracken B inhibits various key bacterial enzymes and proteins, including DNA gyrase (GYRA), fatty acid synthase (FABI), and dihydrofolate reductase (DHFR), interfering with bacterial DNA replication, lipid synthesis, and metabolism, thereby exerting antibacterial effects.

Druggability evaluation and pharmacokinetics

Druggability evaluation of fernin B shows it has promising potential for drug development:

• Moderate molecular weight (218.2960), conforming to the Lipinski rule, favorable for oral absorption.
• Moderate lipophilic (LogP 2.7746) promotes cell membrane penetration and supports good bioavailability.
• Low polarity surface area (TPSA 37.3) helps cross the blood-brain barrier, making it suitable for treating central nervous system diseases.
• Limited water solubility (0.0645 mg/mL), which may affect dissolution rate and absorption, requiring formulation optimization and improvement.
• No hERG inhibitory activity, reducing the risk of cardiotoxicity.
• Ames test is negative, indicating relatively high safety.

Pharmacokinetics, fern B exhibits good oral absorption and blood-brain barrier crossing ability, is widely distributed in the body, metabolically stable, and excreted mainly by liver and renal excretion. In the future, further systematic research is needed on its half-life, metabolites, and drug interactions to provide data support for clinical applications.

Prospects and outlooks for clinical applications

As a multi-target natural product, fern B possesses broad pharmacological activity and good druggability, demonstrating clinical application potential across various disease fields:

• Osteoarthritis: By inhibiting chondrocyte hypertrophy and inflammatory responses, fern B is expected to become a disease-modifying drug for osteoarthritis, alleviating symptoms and slowing disease progression.
• Alzheimer's Disease: Its role in reducing β-amyloid deposition and improving cognitive function provides a new strategy for AD treatment, especially suitable for early intervention.
• Pathological cardiac hypertrophy: Inhibits myocardial hypertrophy and improves cardiac function; may be used as an adjunct treatment for heart failure and related cardiovascular diseases.
• Diabetes and metabolic syndrome: Regulates blood sugar and metabolism, helping to improve diabetes and its complications.
• Antibacterial therapy: Multi-target antibacterial mechanisms offer new ideas for anti-infective drug development, especially with potential value in the prevention and control of drug-resistant bacteria.

Future research should focus on preclinical safety evaluation, pharmacokinetic optimization, formulation development, and clinical trial design for fern B, promoting its translation from laboratory research to clinical application. At the same time, combining modern medicinal chemistry and pharmacological technologies, structural modification and derivative design are carried out to enhance activity and selectivity, expanding application fields.

Conclusion

Frenin B, a natural inmanketone compound derived from bracken, demonstrates therapeutic potential in various diseases such as osteoarthritis, Alzheimer's disease, cardiac hypertrophy, and diabetes due to its unique chemical structure and multi-target pharmacological activity. Its excellent druggability parameters and safety lay the foundation for subsequent drug development. With further research, fern B is expected to become a new generation of natural medicine or lead compound, offering new drug options and therapeutic strategies for related diseases. Future research needs to strengthen molecular-level analysis of its mechanism of action, optimize pharmacokinetic characteristics, and promote clinical translational processes to fully realize its unique value in the field of natural product pharmacology.