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2,5-Dibromophenylacetic acid (CAS# 203314-28-7), also known as 2-(2,5-dibromophenyl)acetic acid or benzeneacetic acid, 2,5-dibromo-, is a regioselectively dibrominated arylacetic acid with the molecular formula C₈H₆Br₂O₂ and a molecular weight of 293.94 g/mol. Its molecular structure consists of a phenylacetic acid core bearing bromine atoms at the 2- and 5-positions of the aromatic ring. This specific 2,5-dibromo substitution pattern—distinguishing it from other dibromophenylacetic acid regioisomers—confers unique electronic and steric properties that directly influence its reactivity in cross-coupling reactions and the biological activity of downstream pharmaceutical derivatives.

As a white crystalline powder with a melting point of 104–108°C, the compound is slightly soluble in water but more soluble in organic solvents such as ethanol and dichloromethane. It is stable under recommended storage conditions (sealed, dry, room temperature) and is typically supplied at ≥98% purity (HPLC). The compound is classified with the signal word “Warning” under GHS, with hazard statements H302 (Harmful if swallowed), H315 (Causes skin irritation), H319 (Causes serious eye irritation), H332 (Harmful if inhaled), and H335 (May cause respiratory irritation).

2,5-Dibromophenylacetic acid is a strategically important regioselective dibromo arylacetic acid building block that serves as the definitive intermediate in the synthesis of Elbasvir (MK-8742) —a FDA-approved HCV NS5A inhibitor developed by Merck for the treatment of chronic hepatitis C virus infection. Its unique combination of a 2,5-dibromo substitution pattern, an arylacetic acid handle, and orthogonal reactivity at the two bromine positions positions it as an indispensable building block in antiviral drug development and medicinal chemistry. Based on its chemical characteristics and industrial significance, this article systematically analyzes the key properties, core application areas, global market structure, regulatory landscape, and future outlook of this strategically important halogenated aromatic building block.

Key Properties and Reactivity Profile

2,5-Dibromophenylacetic acid (CAS# 203314-28-7) is a regioselectively dibrominated arylacetic acid whose value derives from the orthogonal reactivity of its two bromine substituents and the carboxylic acid functionality.

Key physicochemical parameters include:

Molecular Formula: C₈H₆Br₂O₂
Molecular Weight: 293.94 g/mol
CAS Number: 203314-28-7
MDL Number: MFCD02664691
Synonyms: 2-(2,5-Dibromophenyl)acetic acid; Benzeneacetic acid, 2,5-dibromo-; 2,5-Dibromobenzeneacetic acid
IUPAC Name: 2-(2,5-dibromophenyl)acetic acid
Appearance: White crystalline powder
Purity: ≥97% and ≥98% (HPLC) available
Melting Point: 104–108°C
Boiling Point: 376.4±27.0°C at 760 mmHg (predicted)
Density: 1.969±0.06 g/cm³ (predicted)
Flash Point: 181.5±23.7°C
pKa: 3.87±0.10 (predicted)
LogP: 3.08 (XLogP3); 2.83870
Topological Polar Surface Area: 37.3 Å²
Storage: Sealed in dry, room temperature; protect from light and moisture
SMILES: C1=CC(=C(C=C1Br)CC(=O)O)Br
InChIKey: NKZKFWYEXDBOTP-UHFFFAOYSA-N
GHS Classification: Warning; H302 (Harmful if swallowed), H315 (Causes skin irritation), H319 (Causes serious eye irritation), H332 (Harmful if inhaled), H335 (May cause respiratory irritation)
Transport Classification: Not classified as hazardous material for DOT/IATA transport
HS Code: 2916.39 (aromatic monocarboxylic acids)

The compound’s reactivity is defined by its two orthogonal handles: the carboxylic acid group enables amide coupling, esterification, and salt formation, while the two bromine atoms at the 2- and 5-positions provide sites for palladium-catalyzed cross-coupling reactions (Suzuki-Miyaura, Buchwald-Hartwig, Sonogashira). The regioselective placement of the bromine atoms is critical—the 2-bromo substituent is ortho to the acetic acid side chain, while the 5-bromo substituent is para to the acetic acid handle. This specific substitution pattern is essential for the synthesis of Elbasvir, as the 2,5-dibromophenylacetic acid scaffold provides the precise molecular geometry required for HCV NS5A inhibition. The compound is used as a reactant in the synthesis of MK-8742 (Elbasvir), where its two bromine atoms enable sequential cross-coupling reactions to construct the complex biaryl architecture of the HCV NS5A inhibitor.

Core Application Fields and Demand

Market demand for 2,5-dibromophenylacetic acid (CAS# 203314-28-7) is concentrated in three primary sectors: pharmaceutical synthesis and antiviral drug manufacturing (approximately 65–70% of global consumption), pharmaceutical intermediate manufacturing and drug discovery (approximately 20–25%), and specialty chemical synthesis and research applications (approximately 10–15%). Its role as the definitive intermediate for Elbasvir and its utility as a regioselective dibromo building block serve as the core drivers of sustained demand growth.

In pharmaceutical synthesis and antiviral drug manufacturing, 2,5-dibromophenylacetic acid is the essential intermediate in the synthesis of Elbasvir (MK-8742, Zepatier®) —a FDA-approved HCV NS5A inhibitor developed by Merck for the treatment of chronic hepatitis C virus genotypes 1 and 4 infection. The compound is used as a reactant in the synthesis of MK-8742, where its 2,5-dibromophenylacetic acid scaffold provides the critical molecular framework for HCV NS5A inhibition. The synthetic route involves the sequential functionalization of the two bromine atoms to construct the complex biaryl architecture characteristic of NS5A inhibitors. Elbasvir is a component of Zepatier®, a fixed-dose combination therapy that has been approved for the treatment of chronic HCV infection in adults. The compound is also used in the synthesis of deuterium-modified Elbasvir derivatives —a next-generation approach to improving pharmacokinetic properties of antiviral drugs. The compound is also used as a reactant in the preparation of N-(4-amino-5-cyano-6-ethoxypyridin-2-yl)-2-(2,5-dibromophenyl)acetamide, a c-Jun N-terminal kinase (JNK) inhibitor with cellular activity and minimal cross-kinase activity, demonstrating its utility in kinase inhibitor development.

In pharmaceutical intermediate manufacturing and drug discovery, 2,5-dibromophenylacetic acid serves as a valuable building block for the synthesis of complex pharmaceutical compounds. The compound is used as a high-value pharmaceutical intermediate and fine chemical raw material, widely applied in the skeleton construction of innovative active pharmaceutical ingredients (APIs) and the development of complex pharmaceutical synthesis mechanisms. Its unique 2,5-dibromo substitution pattern enables the construction of diverse molecular architectures through sequential cross-coupling reactions, making it valuable for medicinal chemistry programs targeting viral infections and other therapeutic areas. The compound is classified as a pharmaceutical intermediate and is used in the synthesis of certain drugs as an intermediate or raw material.

In specialty chemical synthesis and research applications, 2,5-dibromophenylacetic acid is used as an intermediate for the synthesis of other organic compounds, including certain high-performance resins. It also serves as a reagent and catalyst in chemical research, with applications in various organic transformations. The compound is employed in the synthesis of BODIPY-based photochemical catalysts for the oxidation dehydrogenation synthesis of indole derivatives, demonstrating its utility in photochemical applications.

Major Market Participants

The global supply system for 2,5-dibromophenylacetic acid (CAS# 203314-28-7) features a pattern of “specialized pharmaceutical intermediate manufacturers, multinational research chemical distributors, and Chinese producers serving distinct market segments.” As a specialized regioselective dibromo building block rather than a bulk commodity, the market is characterized by a moderate number of suppliers catering to pharmaceutical R&D, API manufacturing, and academic research.

In the global research and high-purity segment, key international suppliers include BOC Sciences, offering the compound as a building block for Elbasvir synthesis with over 20,000 building blocks and intermediates from stock, process scale-up from lab to industrial scale, and flexible batch sizes. Fluorochem (UK) offers the compound at 98% purity under product code F212995, with stock availability in the UK, Germany, and China, and packaging sizes from 5 g (£10.00) to 500 g (£566.00). AK Scientific (AKSci) offers the compound at 98% (HPLC) purity under product code W4286, with bulk reagent availability. CymitQuimica offers the compound at ≥95% purity with pricing from €32.00 for 1 g to €56.00 for 25 g. US Biological offers the compound under catalog number 273203 for research applications. Fujifilm Wako Pure Chemical offers the compound under product number 066946 with 1 g packaging priced at ¥11,000 and 5 g at ¥34,000. Parchem offers the compound as a bulk fine and specialty chemical from its ISO 9001:2015 certified facility. These suppliers serve the pharmaceutical, biotechnology, and academic research communities with products that meet rigorous quality specifications.

In the industrial and large-scale production segment, Chinese manufacturers have emerged as significant players in the global supply chain. XinChem is a reliable manufacturer and supplier of high-purity 2,5-dibromophenylacetic acid from China, offering the compound with stringent quality standards for use in Elbasvir synthesis, HCV NS5A inhibitor development, and pharmaceutical intermediate applications. XinChem provides the compound as a white crystalline powder with comprehensive quality documentation, batch-specific Certificates of Analysis (COA), customizable packaging, and globally compliant REACH, ISO 9001, and GMP-aligned manufacturing. Chinese manufacturers offer the compound at various purity grades (typically 98–99%) and packaging options—from grams to multi-kilogram quantities—serving both domestic and export markets. Production scale capabilities include 1 kg and 25 kg quantities from industrial suppliers, with minimum order quantities as low as 250 g for research applications. The compound is available at prices ranging from approximately ¥29.90 for 250 mg to ¥25.90 per gram for bulk quantities from Chinese suppliers.

Regional Market Dynamics

The global 2,5-dibromophenylacetic acid market exhibits distinct regional characteristics, with production concentrated in Asia-Pacific (particularly China) and consumption distributed across North America, Europe, and the Asia-Pacific region, aligned with the pharmaceutical, antiviral drug, and specialty chemical industries in these regions. The global market for this compound is driven by the continued growth of HCV antiviral therapies, particularly NS5A inhibitors, and the expanding pipeline of fluorinated and halogenated pharmaceutical intermediates.

The Asia-Pacific region is a significant production hub for 2,5-dibromophenylacetic acid, with China hosting numerous manufacturers and suppliers including XinChem. The region’s competitive advantages include lower production costs, established chemical infrastructure, and proximity to rapidly growing pharmaceutical industries. Chinese suppliers offer the compound at various purity grades (typically 98–99%) and packaging options, serving both domestic and export markets. The compound is classified as a pharmaceutical intermediate and fine chemical raw material in the Chinese market, with multiple suppliers offering the product in packaging sizes ranging from 250 mg to 25 kg. The region’s growing pharmaceutical R&D and API manufacturing sectors, particularly in antiviral drug development, continue to drive regional consumption growth.

North America remains a key market for high-purity and research-grade 2,5-dibromophenylacetic acid, driven by demand from the pharmaceutical industry, biotechnology companies, and academic research institutions. The United States hosts numerous research organizations, pharmaceutical companies, and contract research organizations that require high-quality halogenated building blocks for Elbasvir manufacturing, HCV NS5A inhibitor development, and kinase inhibitor drug discovery. BOC Sciences, AK Scientific, and US Biological serve the North American market with extensive distribution networks. The region’s well-established regulatory framework, including FDA oversight of antiviral drug manufacturing, supports demand for high-grade research chemicals and pharmaceutical intermediates.

Europe is characterized by stringent regulatory requirements, including REACH registration, and a strong focus on quality and sustainability in pharmaceutical and chemical research. European pharmaceutical companies, antiviral drug manufacturers, and research institutions demand high-purity halogenated building blocks with comprehensive documentation. Fluorochem (UK) and CymitQuimica serve the European market with in-stock availability. The compound is listed in the EU TARIC database with a 0% autonomous duty rate for (2,5-dibromophenyl)acetic acid (CAS RN 203314-28-7) with a purity by weight of 98.0% or more, reflecting the European Union’s recognition of the compound’s pharmaceutical importance.

Japan represents a specialized market where 2,5-dibromophenylacetic acid is supplied by Fujifilm Wako Pure Chemical and other distributors for pharmaceutical research, antiviral drug development, and fine chemical applications.

Regulatory and Safety Considerations

As a halogenated arylacetic acid and pharmaceutical intermediate, 2,5-dibromophenylacetic acid (CAS# 203314-28-7) is subject to regulatory oversight in major global economies. Compliance with relevant regulations is essential for market access and trade.

GHS classification and handling: 2,5-Dibromophenylacetic acid is classified with the signal word ”Warning” . Hazard statements include H302 (Harmful if swallowed), H315 (Causes skin irritation), H319 (Causes serious eye irritation), H332 (Harmful if inhaled), and H335 (May cause respiratory irritation). The compound is classified as Acute Tox. 4 (Oral) , Acute Tox. 4 (Inhalation) , Skin Irrit. 2, Eye Irrit. 2, and STOT SE 3 (respiratory system). Precautionary statements include P261 (Avoid breathing dust/fume/gas/mist/vapours/spray), P264 (Wash skin thoroughly after handling), P270 (Do not eat, drink or smoke when using this product), P271 (Use only outdoors or in a well-ventilated area), P280 (Wear protective gloves/protective clothing/eye protection/face protection), P301+P312 (IF SWALLOWED: Call a POISON CENTER/doctor if you feel unwell), P302+P352 (IF ON SKIN: Wash with plenty of soap and water), P304+P340 (IF INHALED: Remove person to fresh air and keep comfortable for breathing), P305+P351+P338 (IF IN EYES: Rinse cautiously with water for several minutes; remove contact lenses if present and easy to do; continue rinsing), and P405 (Store locked up). The compound is considered hazardous according to OSHA 29 CFR 1910.1200.

Storage and stability: 2,5-Dibromophenylacetic acid should be stored sealed in a dry, well-ventilated area at room temperature, protected from light and moisture. The compound is stable under recommended storage conditions but should be kept away from strong oxidizing agents.

Regulatory compliance: In the European Union, the compound must comply with REACH registration requirements for import and use. The compound is listed in the EU TARIC database under code 90/78 for (2,5-dibromophenyl)acetic acid (CAS RN 203314-28-7) with a purity by weight of 98.0% or more, with a 0% autonomous duty rate. Manufacturers and suppliers must provide comprehensive Safety Data Sheets (SDS) and maintain appropriate documentation. In the United States, 2,5-dibromophenylacetic acid is intended for research and development use only and is not intended for therapeutic, food, cosmetic, or consumer applications unless explicitly stated otherwise. For pharmaceutical intermediate applications, manufacturers must comply with relevant FDA regulations and quality standards.

Transport information: 2,5-Dibromophenylacetic acid is not classified as hazardous material for DOT/IATA transport purposes. Proper packaging, labeling, and documentation are nevertheless required for international shipping. The HS code for the compound is 2916.39 (aromatic monocarboxylic acids). The compound is typically shipped at ambient temperature with appropriate protection from moisture and light.

Future Outlook

The market outlook for 2,5-dibromophenylacetic acid is positive, supported by several key growth drivers across its major application segments. While the compound remains a relatively specialized regioselective dibromo building block, its essential role as the intermediate for Elbasvir and its utility in HCV NS5A inhibitor development position it for steady growth in the coming years. The global market for this compound is driven by the continued growth of HCV antiviral therapies and the expanding pipeline of halogenated pharmaceutical intermediates.

Key growth drivers include:

Expansion of the HCV antiviral market: The continued global demand for Elbasvir (MK-8742) and other HCV NS5A inhibitors—driven by the high prevalence of chronic hepatitis C infection worldwide—drives demand for the key intermediate 2,5-dibromophenylacetic acid. Elbasvir is a component of Zepatier®, a fixed-dose combination therapy approved for the treatment of chronic HCV genotypes 1 and 4 infection. The compound’s role as a required reactant in the preparation of MK-8742 positions it at the forefront of HCV antiviral drug manufacturing.
Growth in antiviral drug development: The increasing global focus on antiviral drug discovery, particularly for emerging viral pathogens, drives demand for versatile halogenated building blocks. The compound’s demonstrated utility in the synthesis of Elbasvir and deuterium-modified Elbasvir derivatives supports sustained demand from antiviral R&D programs.
Expansion of kinase inhibitor research: The compound’s use as a reactant in the preparation of N-(4-amino-5-cyano-6-ethoxypyridin-2-yl)-2-(2,5-dibromophenyl)acetamide (6q)—a JNK inhibitor with cellular activity and minimal cross-kinase activity—demonstrates its utility in kinase inhibitor development and supports demand from oncology and inflammation drug discovery programs.
Increasing demand for regioselective halogenated building blocks: The growing emphasis on regioselective synthesis and the construction of complex molecular architectures in medicinal chemistry drives demand for 2,5-dibromophenylacetic acid as a precisely functionalized building block for sequential cross-coupling reactions.
Expansion of pharmaceutical R&D in Asia: The growth of pharmaceutical R&D and API manufacturing in China and India—driven by increasing investment in generic drug production and innovative drug discovery—supports demand for high-quality pharmaceutical intermediates and building blocks. The compound’s listing in the EU TARIC database with a 0% duty rate for 98%+ purity material reflects the European Union’s recognition of its pharmaceutical importance.

Challenges and considerations:

Hazardous material handling: The compound’s classification as acutely toxic (H302, H332) and irritant (H315, H319, H335) requires appropriate safety measures during handling and storage.
Limited scale: As a specialized pharmaceutical intermediate, the market for 2,5-dibromophenylacetic acid is smaller than that of commodity chemicals.
Competition from alternative building blocks: The market faces competition from other dibromophenylacetic acid regioisomers and alternative synthetic routes to Elbasvir intermediates.
Regulatory compliance: Increasingly stringent pharmaceutical and chemical regulations may require ongoing investment in quality systems and documentation.

To succeed in this evolving market landscape, suppliers must focus on product quality (particularly regioisomeric purity and batch-to-batch consistency), supply chain reliability, regulatory compliance, and responsive customer service. Companies that can offer high-purity products, flexible packaging options, and technical support for pharmaceutical, antiviral drug development, and medicinal chemistry applications will be well-positioned to capture growing demand.

Shanghai XinChem Co., Ltd. (XinChem)

As a world-leading supplier of organic chemicals and pharmaceutical intermediates, Shanghai XinChem Co., Ltd. (XinChem) is dedicated to meeting the innovative needs of the pharmaceutical, antiviral drug, and fine chemical industries. Leveraging extensive experience and advanced manufacturing capabilities, XinChem provides high-quality 2,5-Dibromophenylacetic Acid (CAS# 203314-28-7) to customers worldwide. As a trusted manufacturer and supplier based in China, XinChem combines competitive pricing, reliable supply, and exceptional service to establish itself as a preferred partner for pharmaceutical companies, antiviral drug developers, and research institutions seeking this versatile regioselective dibromo arylacetic acid building block.

1. Technical Advantages

Advanced Synthesis and Purification Processes
XinChem utilizes state-of-the-art manufacturing facilities and rigorous quality control measures to ensure the purity, consistency, and safety of its 2,5-dibromophenylacetic acid products. The production process incorporates established synthetic routes—including the bromination of phenylacetic acid derivatives with controlled regioselectivity to achieve the 2,5-dibromo substitution pattern, followed by purification to remove regioisomeric impurities. This enables the delivery of products with purity ≥98% (HPLC) and ≥99% available to meet diverse application requirements. Strict process control ensures consistent regioisomeric purity, minimal impurities, and batch-to-batch reproducibility, providing customers with reliable performance in Elbasvir synthesis, HCV NS5A inhibitor development, and pharmaceutical intermediate manufacturing. XinChem’s product is characterized by its white crystalline powder appearance, melting point of 104–108°C, and high chemical purity suitable for demanding pharmaceutical applications.

Full-Chain Quality Control
The production process strictly adheres to international quality standards, with comprehensive quality control covering raw material sourcing, in-process monitoring, and finished product testing. Each batch is accompanied by a detailed Certificate of Analysis (COA) documenting physical and chemical properties, purity data (HPLC), melting point, and impurity profiles. XinChem offers batch-specific COA, customizable packaging, and globally compliant REACH, ISO 9001, and GMP-aligned manufacturing.

2. Product Advantages

High Purity and Consistent Quality
XinChem offers 2,5-dibromophenylacetic acid with purity ≥98% (HPLC) and ≥99% available, ensuring optimal performance in Elbasvir synthesis, HCV NS5A inhibitor development, and pharmaceutical intermediate applications. The product’s high purity and consistent regioisomeric quality minimize the risk of unwanted side reactions and impurities, making it suitable for demanding applications in antiviral drug manufacturing and drug discovery.

Comprehensive Specifications
Key specifications include:

Molecular Formula: C₈H₆Br₂O₂
Molecular Weight: 293.94 g/mol
CAS Number: 203314-28-7
Synonyms: 2-(2,5-Dibromophenyl)acetic acid; Benzeneacetic acid, 2,5-dibromo-; 2,5-Dibromobenzeneacetic acid
MDL Number: MFCD02664691
Appearance: White crystalline powder
Purity: ≥98% (HPLC) / ≥99% available
Melting Point: 104–108°C
Boiling Point: 376.4±27.0°C at 760 mmHg
Density: 1.969±0.06 g/cm³
pKa: 3.87±0.10
LogP: 3.08 (XLogP3)
Storage: Sealed in dry, room temperature; protect from light and moisture
GHS Classification: Warning; H302, H315, H319, H332, H335
HS Code: 2916.39

Flexible Packaging Solutions
XinChem provides a range of packaging options to accommodate diverse customer needs, from laboratory-scale quantities (250 mg, 1 g, 5 g) to industrial-scale packaging (25 g, 100 g, 500 g, 1 kg, 25 kg) and bulk shipments. Customized packaging solutions are available upon request, ensuring safe handling, storage, and transportation with appropriate protection from light and moisture.

3. Application Fields

As a versatile regioselective dibromo arylacetic acid building block, 2,5-Dibromophenylacetic Acid (CAS# 203314-28-7) exhibits wide application value across multiple industries:

Pharmaceutical Synthesis and Antiviral Drug Manufacturing:

Essential intermediate for Elbasvir (MK-8742, Zepatier®), a FDA-approved HCV NS5A inhibitor for chronic hepatitis C genotypes 1 and 4
Key reactant in the synthesis of deuterium-modified Elbasvir derivatives
Precursor for N-(4-amino-5-cyano-6-ethoxypyridin-2-yl)-2-(2,5-dibromophenyl)acetamide (6q), a JNK inhibitor with cellular activity
Building block for HCV NS5A inhibitors and other antiviral agents

Pharmaceutical Intermediate Manufacturing and Drug Discovery:

High-value pharmaceutical intermediate for skeleton construction of innovative APIs
Versatile building block for complex pharmaceutical synthesis mechanisms
Precursor for cross-coupling reactions (Suzuki-Miyaura, Buchwald-Hartwig) to construct biaryl architectures

Specialty Chemical Synthesis and Research:

Intermediate for high-performance resins and specialty organic compounds
Precursor for BODIPY-based photochemical catalysts for indole oxidation dehydrogenation synthesis
Reagent and catalyst for various organic transformations

4. Service Support

Technical Expertise and Customized Solutions
XinChem’s team of experienced chemists and pharmaceutical scientists provides full technical support throughout the customer journey—from product selection and specification development to application guidance and troubleshooting. Whether customers require optimization of cross-coupling reaction conditions, guidance on regioisomeric purity assessment, or assistance with regulatory documentation, XinChem’s technical experts are ready to help. Custom synthesis and contract manufacturing with flexible scaling from R&D to commercial quantities are available upon request.

Global Logistics and Reliable Supply
With established supply chains serving markets across Europe, North America, Asia-Pacific, and beyond, XinChem ensures timely delivery and consistent product availability. The company’s logistics team manages all aspects of international shipping, including customs clearance and documentation, with appropriate protection from moisture and light for product stability.

Regulatory Support
XinChem provides comprehensive documentation to support regulatory compliance, including Safety Data Sheets (SDS), Certificates of Analysis (COA), and other required certificates. The company stays current with evolving regulatory requirements in major markets, including REACH, TSCA, and other regional regulations, helping customers navigate the complexities of global trade.

5. Reasons to Choose XinChem

Professionalism: Extensive experience and deep expertise in halogenated aromatic building block synthesis and supply.
Quality: Rigorous quality control, high purity (≥98% to ≥99%), regioisomeric specificity, and adherence to international standards.
Reliability: Stable supply, competitive pricing, and timely delivery.
Flexibility: Customized solutions to meet diverse customer needs, including custom synthesis and packaging.
Service: Responsive technical support and comprehensive documentation including batch-specific COA.

Website: www.xinchem.com

Email: sales1@xinchem.com

WhatsApp: +86 18049800532

Post time: Sep-27-2026

The Regioselective Dibromo Arylacetic Acid Building Block for Elbasvir, HCV NS5A Inhibitors, and Antiviral Drug Development: 2,5-Dibromophenylacetic Acid (CAS# 203314-28-7)