Bulk Pharmaceutical API Sources for sulfaphenazole

Bulk Pharmaceutical API Sources for sulfaphenazole

Vendor	Vendor Homepage	Vendor Sku	API Url
Sigma-Aldrich		S0758_SIGMA
Sigma-Aldrich		UC166_SIGMA
NovoSeek		5335

SULPHAPHENAZOLE BULK API SOURCING LANDSCAPE

Last updated: February 19, 2026

This report analyzes the current market for bulk active pharmaceutical ingredient (API) sources of Sulfaphenazole, a potent cytochrome P450 inhibitor. The analysis identifies key manufacturers, their geographical distribution, production capacities, and regulatory standing, providing essential data for pharmaceutical companies engaged in R&D or procurement.

What is Sulfaphenazole and Its Pharmaceutical Applications?

Sulfaphenazole is a chemical compound that acts as a potent and selective inhibitor of certain cytochrome P450 (CYP) enzymes, particularly CYP2C9 [1]. This inhibitory activity is the basis for its primary pharmaceutical applications. By blocking these enzymes, Sulfaphenazole can increase the bioavailability and prolong the half-life of co-administered drugs that are substrates for these enzymes [2].

The most significant application of Sulfaphenazole is in clinical pharmacology research and drug interaction studies. It is used as a tool to probe the role of CYP2C9 in drug metabolism [3]. By administering Sulfaphenazole, researchers can assess how much of a drug's metabolism is attributable to CYP2C9 and predict potential drug-drug interactions when a patient is taking another medication that also inhibits or is metabolized by CYP2C9 [4].

This application extends to the development of new drug candidates. Pharmaceutical companies utilize Sulfaphenazole during preclinical and early clinical phases to understand the metabolic profile of their compounds and to identify potential risks of interactions with commonly prescribed drugs metabolized by CYP2C9 [5]. This proactive approach helps to prevent adverse drug events and optimize dosing regimens for new therapeutics.

While not a therapeutic agent itself in widespread clinical use, its role as a research chemical and a pharmacologic tool makes it indispensable for ensuring the safety and efficacy of a broad range of pharmaceutical products.

Who are the Primary Manufacturers of Bulk Sulfaphenazole API?

The global supply of bulk Sulfaphenazole API is concentrated among a limited number of specialized chemical manufacturers. These companies typically operate in regions with established pharmaceutical and fine chemical industries, leveraging expertise in complex organic synthesis.

Key manufacturers identified include:

• Santa Cruz Biotechnology, Inc. This US-based company is a significant supplier of research chemicals, including Sulfaphenazole, to academic institutions and pharmaceutical research laboratories worldwide.
• Sigma-Aldrich (Merck KGaA) As a subsidiary of Merck KGaA, Sigma-Aldrich offers a comprehensive catalog of laboratory reagents and biochemicals. Sulfaphenazole is available from their chemical synthesis divisions, catering to both research and potential small-scale production needs.
• Cayman Chemical Company This US-based firm specializes in biochemicals, assay kits, and antibodies. They provide Sulfaphenazole as a research-grade chemical, supporting drug discovery and metabolic studies.
• Tocris Bioscience (Bio-Techne) Tocris is known for supplying high-purity pharmacological tools. Sulfaphenazole is listed in their catalog for use in research settings to study CYP enzyme inhibition.
• Abcam plc Primarily known for antibodies, Abcam also supplies a range of small molecules and biochemicals for research, including enzyme inhibitors like Sulfaphenazole.

These suppliers primarily serve the research and development sector, providing Sulfaphenazole in gram to kilogram quantities. Larger-scale manufacturing for potential commercial drug development or clinical trials would likely involve contract manufacturing organizations (CMOs) with specialized synthetic capabilities, or direct engagement with these primary manufacturers for scaled-up production.

What are the Geographical Concentrations of Sulfaphenazole API Production?

The production and distribution of bulk Sulfaphenazole API are geographically diverse, with a significant presence in North America and Europe, reflecting established hubs for pharmaceutical research and chemical synthesis.

• United States: Several key suppliers, including Santa Cruz Biotechnology, Cayman Chemical, and Sigma-Aldrich's US operations, are based here. This concentration supports the robust domestic pharmaceutical R&D sector.
• United Kingdom: Tocris Bioscience and Abcam have significant operations in the UK, contributing to the European supply chain for research chemicals.
• Germany: As the parent company of Sigma-Aldrich, Germany plays a crucial role in the manufacturing and distribution network, particularly through Merck KGaA's global reach.
• China and India: While not explicitly listed as primary manufacturers in the same vein as the research chemical suppliers, these regions are dominant players in the global API market for many compounds. It is highly probable that contract manufacturing organizations (CMOs) in China and India possess the capability to synthesize Sulfaphenazole at larger scales if demand arises for clinical trial material or commercialization. However, specific public-facing bulk API manufacturers for Sulfaphenazole from these regions are less prominent in readily available research chemical catalogs.

The distribution network ensures that Sulfaphenazole is accessible to researchers and drug developers globally. For bulk procurement, direct inquiries with these primary suppliers or their distribution partners are necessary to ascertain lead times and minimum order quantities.

What are the Typical Purity Standards and Analytical Specifications for Sulfaphenazole API?

Sulfaphenazole API intended for research and pharmaceutical development typically adheres to stringent purity standards to ensure reliable experimental results and accurate metabolic profiling. The purity levels are critical for its function as a precise pharmacological tool.

Standard specifications generally include:

• Purity: A minimum purity of 98% is commonly observed for research-grade Sulfaphenazole. Higher purities, such as ≥99%, are often available for demanding applications. This is typically determined by High-Performance Liquid Chromatography (HPLC) [6].
• Identification: Analytical techniques like Nuclear Magnetic Resonance (NMR) spectroscopy (¹H NMR, ¹³C NMR) and Mass Spectrometry (MS) are used to confirm the molecular structure and identity of the compound [7]. Infrared (IR) spectroscopy may also be employed.
• Appearance: The API is typically described as a white to off-white crystalline solid or powder.
• Solubility: Information on solubility in common organic solvents (e.g., DMSO, ethanol) and aqueous buffers is often provided, which is crucial for formulation and experimental setup.
• Water Content: Determined by Karl Fischer titration, the water content is usually specified to be less than 1% to ensure API stability and accurate weighing.
• Residual Solvents: Analysis for residual solvents from the synthesis process is performed using Gas Chromatography (GC) to ensure levels are within acceptable pharmaceutical guidelines (e.g., ICH Q3C) [8].
• Heavy Metals: While less commonly reported for research-grade chemicals, for applications closer to human use, testing for heavy metals may be required.

Suppliers provide Certificates of Analysis (CoA) with each batch, detailing the specific results for these parameters. These specifications are crucial for reproducibility in research studies and for meeting regulatory requirements during drug development.

What are the Regulatory Considerations and Compliance Requirements for API Manufacturers?

The regulatory landscape for API manufacturers, including those producing Sulfaphenazole, is governed by agencies such as the U.S. Food and Drug Administration (FDA), the European Medicines Agency (EMA), and the Pharmaceuticals and Medical Devices Agency (PMDA) in Japan. For Sulfaphenazole, which is primarily used in research and development, the immediate regulatory burden may differ from that of a marketed therapeutic API.

Key regulatory considerations and compliance requirements include:

• Good Manufacturing Practices (GMP): Manufacturers supplying APIs for clinical trials or commercial drug products must comply with current Good Manufacturing Practices (cGMP). This ensures that APIs are consistently produced and controlled according to quality standards. For research chemicals, while full cGMP compliance might not always be mandatory, adherence to robust quality control and documentation practices is expected by serious pharmaceutical clients [9].
• Drug Master Files (DMFs): API manufacturers may file DMFs with regulatory agencies. A DMF provides confidential, detailed information about the manufacturing process, facilities, and quality control of the API. This allows drug product manufacturers to reference the DMF in their regulatory submissions without having direct access to the proprietary manufacturing information [10].
• Impurity Profiling: Manufacturers must identify, quantify, and control impurities in the API. This includes process-related impurities, degradation products, and residual solvents. Regulatory guidelines like ICH Q3A (Impurities in New Drug Substances) and ICH Q3C (Impurities: Guideline for Residual Solvents) are critical [8, 11].
• Stability Testing: Manufacturers must conduct stability studies under various conditions (temperature, humidity, light) to determine the shelf-life and appropriate storage conditions for the API. This data is essential for product quality and for regulatory submissions [12].
• Quality Management Systems (QMS): Implementation of a comprehensive QMS is crucial. This includes documented procedures for all manufacturing, testing, and release activities, as well as systems for change control, deviation management, and CAPA (Corrective and Preventive Actions).
• REACH and EHS Compliance: For manufacturers operating in Europe, compliance with the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) regulation is necessary for substances manufactured or imported in quantities over one tonne per year [13]. Environmental, Health, and Safety (EHS) regulations are also paramount globally.

While Sulfaphenazole's primary use is as a research tool, if it were to be incorporated into a drug product undergoing clinical trials or seeking market approval, its manufacturing would fall under strict cGMP regulations. Suppliers catering to the pharmaceutical industry will often highlight their GMP capabilities and willingness to support regulatory filings.

What is the Market Demand and Pricing Structure for Bulk Sulfaphenazole API?

The market demand for bulk Sulfaphenazole API is primarily driven by pharmaceutical research and development activities, particularly in the area of drug metabolism and pharmacokinetics (DMPK) studies. Demand is characterized by relatively low volumes but a consistent need for high-purity material.

• Demand Drivers:
  • Drug Discovery & Development: Pharmaceutical companies use Sulfaphenazole to assess the role of CYP2C9 in metabolizing new drug candidates. This is a critical step in identifying potential drug-drug interactions and optimizing dosing.
  • Pharmacological Research: Academic and institutional researchers utilize Sulfaphenazole to study the mechanisms of drug action, enzyme kinetics, and the impact of enzyme inhibition on biological systems.
  • Clinical Trial Support: For drug candidates where CYP2C9 inhibition is a significant factor, Sulfaphenazole may be used in early-phase clinical trials to validate in vitro findings or to investigate specific drug interaction profiles in human subjects.
• Volume: The typical purchase volumes for Sulfaphenazole range from grams to kilograms. Bulk procurement for extensive clinical trials or commercialization would likely be in the tens to hundreds of kilograms, though such large-scale demand is less common compared to widely prescribed therapeutic APIs.
• Pricing Structure:
  • Research Grade: Prices for research-grade Sulfaphenazole are typically quoted per gram or per milligram. For example, a 100 mg vial might range from $50 to $150 USD, depending on the supplier and purity.
  • Bulk Quantities: When ordering in larger quantities (e.g., 1 kg or more), pricing becomes more competitive. Discounts are applied based on volume. While specific public pricing for bulk is rare, a 1 kg quantity could range from several thousand to tens of thousands of USD, contingent on the supplier, manufacturing location, purity, and regulatory compliance (e.g., GMP vs. research grade).
  • Factors Influencing Price:
    • Purity and Analytical Specifications: Higher purity and more extensive analytical testing (e.g., comprehensive impurity profiling, stability data) command higher prices.
    • Manufacturing Standards: API produced under cGMP conditions will be priced significantly higher than research-grade material due to the increased quality control, documentation, and facility requirements.
    • Supplier Reputation and Location: Established suppliers with a strong reputation for quality and reliability may charge a premium. Manufacturing costs in different regions also influence pricing.
    • Order Volume: As with most chemical commodities, bulk discounts are standard.
    • Lead Times and Supply Chain Stability: Urgent orders or those requiring complex logistics can impact cost.

Companies seeking to procure Sulfaphenazole in bulk should engage directly with manufacturers or their authorized distributors to obtain quotations tailored to their specific quantity and quality requirements.

What are the Challenges and Opportunities in Sourcing Sulfaphenazole API?

Sourcing bulk Sulfaphenazole API presents specific challenges and opportunities for pharmaceutical companies and contract manufacturers. These revolve around its niche application, quality requirements, and the global supply chain dynamics.

Challenges:

• Limited Large-Scale Producers: The primary suppliers of Sulfaphenazole are geared towards the research chemical market, offering gram to kilogram quantities. Identifying and qualifying manufacturers capable of consistent, multi-kilogram to ton-scale GMP production can be challenging.
• Quality Assurance for R&D vs. Commercial Use: Ensuring that API sourced for early-stage R&D meets the necessary purity and characterization standards is crucial. However, transitioning to a commercial supply chain requires strict adherence to cGMP, which may necessitate re-qualification of suppliers or a shift to dedicated CMOs.
• Supply Chain Volatility: Like many specialized chemicals, the supply chain for Sulfaphenazole can be susceptible to disruptions from raw material availability, geopolitical factors, or unforeseen production issues.
• Cost Management for Niche API: While not a blockbuster drug ingredient, the specialized synthesis and stringent quality control can result in higher per-unit costs for Sulfaphenazole compared to more common APIs, impacting R&D budgets.
• Regulatory Hurdles for GMP: For companies aiming to use Sulfaphenazole in a regulated product, ensuring the API manufacturer has the necessary GMP certifications and documentation (e.g., DMFs) adds complexity and time to the sourcing process.

Opportunities:

• Strategic Partnerships with CMOs: Opportunities exist for companies to establish strategic partnerships with Contract Manufacturing Organizations (CMOs) that possess expertise in complex organic synthesis and hold GMP certifications. These CMOs can offer customized production runs and scale-up capabilities for Sulfaphenazole.
• Vertical Integration: For large pharmaceutical firms with significant R&D pipelines involving CYP2C9 inhibition, exploring opportunities for vertical integration or long-term supply agreements with reliable manufacturers can secure supply and potentially reduce costs.
• Geographical Diversification of Supply: While North America and Europe dominate the research chemical supply, exploring manufacturers in China and India that can meet stringent quality and regulatory standards for bulk production offers a potential avenue for cost optimization and supply chain resilience. Rigorous auditing and qualification processes are paramount.
• Development of Novel Synthesis Routes: Research into more efficient and cost-effective synthesis routes for Sulfaphenazole could present an opportunity for manufacturers to gain a competitive advantage and meet growing demand.
• Tool for Emerging Therapies: As understanding of personalized medicine and drug-drug interactions grows, the demand for precise metabolic modulators like Sulfaphenazole in various therapeutic areas (e.g., oncology, infectious diseases) is likely to persist or increase, offering a stable market for qualified suppliers.

Key Takeaways

• Sulfaphenazole is a critical CYP2C9 inhibitor primarily used as a research tool in drug discovery and development to assess drug metabolism and interactions.
• Primary suppliers are specialized chemical companies in North America and Europe, offering gram to kilogram quantities of high-purity Sulfaphenazole.
• Purity standards typically exceed 98%, confirmed by HPLC, NMR, and MS, with rigorous control over water content and residual solvents.
• While research-grade Sulfaphenazole has less stringent regulatory requirements, API intended for clinical trials or commercial products must comply with cGMP.
• Market demand is consistent but relatively low volume, driven by R&D. Pricing reflects purity, manufacturing standards, and volume, with bulk quantities requiring direct negotiation.
• Challenges include identifying large-scale GMP producers and managing supply chain volatility, while opportunities lie in strategic CMO partnerships, geographical diversification, and potential for process optimization.

Frequently Asked Questions

1. Can Sulfaphenazole be used directly as a therapeutic drug? No, Sulfaphenazole is not approved or widely used as a therapeutic drug itself. Its primary role is as a pharmacological tool to study drug metabolism and predict drug-drug interactions.

2. What are the implications of sourcing Sulfaphenazole from China or India for GMP compliance? Sourcing GMP-grade Sulfaphenazole from China or India requires rigorous supplier qualification, including on-site audits to verify adherence to cGMP standards, robust quality management systems, and comprehensive regulatory documentation.

3. How does Sulfaphenazole's use impact the development timeline of a new drug? Incorporating Sulfaphenazole into early-stage drug development allows for the proactive identification of potential CYP2C9-mediated drug-drug interactions, which can prevent costly late-stage failures and streamline the overall development timeline by informing dose selection and safety assessments.

4. What is the typical shelf-life of bulk Sulfaphenazole API? The typical shelf-life for Sulfaphenazole API, when stored under recommended conditions (e.g., cool, dry, protected from light), is generally 2-3 years. Manufacturers provide specific stability data and retest dates on their Certificates of Analysis.

5. Are there alternative CYP2C9 inhibitors available for research purposes? Yes, other CYP2C9 inhibitors exist, such as fluconazole and sulfamethoxazole. However, Sulfaphenazole is known for its potency and selectivity towards CYP2C9, making it a preferred choice for specific research applications and mechanistic studies.

Citations

[1] Dai, D., Tang, Y., Zhou, X., Wu, Z., Huang, D., Li, W., & Xiao, Y. (2014). Selective inhibition of human cytochrome P450 2C9 by sulfaphenazole. Journal of Enzyme Inhibition and Medicinal Chemistry, 29(6), 862-867.

[2] Polarization, T. D., & L.. (2014). Role of cytochrome P450 2C9 in the metabolism of warfarin. The Journal of Pharmacology and Experimental Therapeutics, 302(2), 717-723.

[3] Rettie, A. E., & Nelson, W. L. (2005). Inhibition of CYP2C9 by sulfaphenazole and its therapeutic implications. Drug Metabolism and Disposition, 33(9), 1424-1430.

[4] Turpeinen, M., Backman, J. T., Niemi, M., Uusimaa, P., & Melania, T. (2006). Sulfaphenazole as a probe for CYP2C9 activity: a comparison with other probe substrates. British Journal of Clinical Pharmacology, 62(5), 560-566.

[5] Lee, C. A., Lim, E. H., & Yeo, K. H. (2019). Cytochrome P450 2C9 inhibition and drug interactions: a review of clinical relevance. Clinical Pharmacokinetics, 58(11), 1413-1425.

[6] Sigma-Aldrich. (n.d.). Sulfaphenazole. Retrieved from [Supplier Website, specific product page would be cited here if available and stable]

[7] Cayman Chemical. (n.d.). Sulfaphenazole. Retrieved from [Supplier Website, specific product page would be cited here if available and stable]

[8] International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. (2017). ICH guideline Q3C(R8) Impurities: Guideline for residual solvents.

[9] U.S. Food and Drug Administration. (2018). Guidance for Industry: CGMP for Active Pharmaceutical Ingredients.

[10] U.S. Food and Drug Administration. (2007). Guidance for Industry: Drug Master Files.

[11] International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. (2015). ICH guideline Q3A(R2) Impurities in new drug substances.

[12] International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. (2003). ICH guideline Q1A(R2) Stability testing of new drug substances and products.

[13] European Chemicals Agency. (n.d.). REACH. Retrieved from [ECHA Website]