Mequindox API CAS 16915-79-0 | ≥98% Veterinary Quinoxaline Antibacterial Agent Manufacturer China

Key Selling Points

✓ Quinoxaline-1,4-Dioxide Antibacterial - DNA Synthesis Inhibitor

✓ High Efficacy Against Brachyspira hyodysenteriae (Swine Dysentery Spirochete)

✓ Gram-Negative > Gram-Positive Spectrum + Anaerobic Activity

✓ Rapid Absorption & Short Half-Life (~2h) - Fast Tissue Distribution

✓ Swine Dysentery + Bacterial Enteritis + Neonatal Diarrhea Reference

✓ Oral & Injectable Formulation Versatility

What Is Mequindox Powder?

Mequindox Powder is a synthetic quinoxaline-1,4-dioxide (QdNO) antibacterial agent developed for veterinary use, structurally related to carbadox and olaquindox. Also known as mequidox or acetylmethaquine, it is widely used in livestock production - particularly in swine - for the treatment of enteric infections caused by Gram-negative bacteria and spirochetes.

Mequindox's defining clinical feature is its strong and specific activity against Brachyspira hyodysenteriae (formerly Treponema hyodysenteriae), the anaerobic spirochete that causes swine dysentery - a severe mucohemorrhagic diarrheal disease of growing pigs. Its antibacterial spectrum favors Gram-negative organisms over Gram-positive, with additional activity against anaerobic bacteria. It is administered orally (5–10 mg/kg body weight, twice daily for 3 days) or by intramuscular injection, and is formulated into premixes, soluble powders and injectable solutions. It is important to note that mequindox has been associated with genotoxicity and carcinogenicity in rodent studies, and its use is subject to strict regulatory controls in many jurisdictions - purchasers must verify compliance with local import and use regulations.

How Does Mequindox Powder Work?

Mequindox Powder exerts its antibacterial effect by inhibiting bacterial deoxyribonucleic acid (DNA) synthesis. As a quinoxaline-N,N'-dioxide, it undergoes enzymatic reduction within susceptible bacterial cells to generate reactive oxygen species and free radical intermediates that damage bacterial DNA, disrupting replication and transcription and ultimately arresting bacterial growth.

Because Mequindox Powder is preferentially active against Gram-negative bacteria and anaerobic spirochetes, it is particularly effective against the Brachyspira species that colonize the porcine large intestine. Pharmacokinetically, mequindox is rapidly absorbed after intramuscular administration - detectable in systemic tissues within 10 minutes of injection in pigs - with a short elimination half-life of approximately 2 hours, meaning it distributes widely but clears quickly from the body. This rapid tissue penetration combined with fast elimination makes it suitable for short-course treatment of acute enteric infections. Its spectrum covers common veterinary pathogens including E. coli, Salmonella, Pasteurella, Brachyspira and certain anaerobic organisms, supporting its use in swine dysentery, bacterial enteritis, neonatal yellow/white scour in piglets, calf diarrhea, paratyphoid and poultry colibacillosis.

What Are the Applications of Mequindox Powder?

Swine Dysentery: The primary indication - treatment and control of mucohemorrhagic dysentery caused by Brachyspira hyodysenteriae in growing and finishing pigs.
Swine Bacterial Enteritis: Used for E. coli and Salmonella-associated enteritis, including neonatal yellow scour and white scour in piglets.
Calf Diarrhea & Paratyphoid: Evaluated for bacterial enteritis and Salmonella paratyphoid in calves and young cattle.
Poultry Enteric Infections: Studied for chicken white diarrhea (Salmonella Pullorum) and avian colibacillosis (E. coli) in flocks.
Pasteurella & Respiratory Infections: Used for Pasteurella multocida-associated respiratory and systemic infections in livestock (adjunctive therapy).

What Is the Difference Between Mequindox and Carbadox?

Feature	Mequindox	Carbadox
CAS	16915-79-0	6804-07-5
Molecular Formula	C₁₁H₁₀N₂O₃	C₁₁H₁₀N₄O₄
Molecular Weight	218.21	262.22
Structure	2-Acetyl-3-methyl QdNO	2-(Quinoxalin-2-ylmethylene)hydrazinecarboxylate QdNO
Primary Use	Swine dysentery treatment	Swine growth promotion + dysentery
Oral Absorption	Good	Good
Genotoxicity	Reported in rodents	Reported in rodents
Regulatory Status	Restricted (China vet use)	Banned in EU/US for growth

How Does Mequindox Compare With Other Swine Dysentery Treatments?

Feature	Mequindox	Tiamulin	Valnemulin	Lincomycin
CAS	16915-79-0	55297-96-6	101312-92-9	154-21-2
Class	Quinoxaline dioxide	Pleuromutilin	Pleuromutilin	Lincosamide
Mechanism	DNA synthesis	50S ribosome	50S ribosome	50S ribosome
B. hyodysenteriae	High	High	High	Moderate
Anaerobes	Yes	Yes	Yes	Yes
Oral/Injectable	Both	Oral	Oral	Both
Growth Promotion	Limited	Yes	Yes	No

How Is Mequindox Powder Manufactured?

Mequindox Powder is manufactured through multi-step chemical synthesis involving quinoxaline ring construction, N-oxidation, acetylation and methylation, followed by purification, crystallization and drying.

Raw Material QC → Quinoxaline Core Synthesis → N,N'-Dioxidation → Acetylation → Methylation → Purification → Crystallization → Drying → Milling → Final QC → Packaging

HDM BIO controls key synthesis, oxidation, purification and crystallization parameters to maintain consistent purity and batch quality.

Quality Specifications

Test Item	Standard	Typical Result
Appearance	Yellow powder	Consistent
Assay (HPLC)	≥98%	99.0%
Identity (IR)	Conforms to reference standard	Confirmed
Melting Point	153–158°C	155°C
Loss on Drying	≤0.5%	0.2%
Residue on Ignition	≤0.1%	Compliant
Heavy Metals	≤10 ppm	Compliant
Related Substances	Within specification	Pass
Residual Solvents	Within specification	Pass

What Quality Control Tests Are Performed for Mequindox Powder?

Each batch undergoes multi-step quality control before release to verify identity, purity and physical properties.

Raw Material QC → In-Process Control → HPLC Assay → IR Identity Verification → Melting Point Determination → Related Substances (HPLC) → Loss on Drying → Heavy Metals → Residue on Ignition → Residual Solvents → Final Batch Release

Key evaluations include identification via infrared (IR) spectroscopy, HPLC active content assay, melting point determination, related substances analysis, loss on drying, heavy metal limits, residue on ignition and residual solvent testing. Every commercial batch is supported by a batch-specific COA and relevant analytical documentation for incoming QC and supplier qualification.

What Factors Affect Mequindox Powder Bulk Price?

Mequindox Powder bulk pricing is driven by several key factors:

Synthesis Costs: Multi-step quinoxaline synthesis and N-oxidation chemistry, including raw material availability, directly influence manufacturing expenses.
Purity & Grade: Higher assay percentages and strict impurity control cost more to produce.
Regulatory Compliance & Certification: GMP-standard API batches with consistent COA and complete export documentation demand a higher price.
Order Volume: Large-scale industrial or wholesale contracts receive steeper per-kilogram discounts than small-batch specialty orders.
Logistics & Geography: Shipping distance, light-protection packaging requirements and customs compliance add to the landed cost.

Contact HDM BIO for a current quotation and volume-based pricing.

Why Choose HDM BIO as Your Mequindox Powder Supplier?

High-purity (≥98% / typical 99%) quinoxaline antibacterial with proven Brachyspira activity
Rapid-absorption, short-half-life profile suitable for acute enteric infection treatment
GMP-aligned production, ISO & HACCP certified quality system
Full batch traceability and complete documentation (COA, MSDS, HPLC)
Flexible supply: gram samples to ton-level bulk orders
Global export to 70+ countries with full customs support

Bulk Packaging, Shipping & Storage

Packaging: Foil bags for samples and moisture-proof fiber drums for bulk orders.
Custom Packaging: OEM labeling available.
Shipping Documents: COA, MSDS/SDS, commercial invoice, packing list and customs documentation available according to order requirements.
Storage: Store tightly sealed in a cool, dry, light-protected environment. Shelf life: 24 months.
Handling: For veterinary raw material use only; not for direct clinical administration.

Frequently Asked Questions About Mequindox Powder

Q1: What is Mequindox Powder?

A: A synthetic quinoxaline-1,4-dioxide antibacterial used in veterinary medicine, primarily for swine dysentery caused by Brachyspira hyodysenteriae and bacterial enteritis in livestock.

Q2: What is the CAS number?

A: 16915-79-0.

Q3: How does mequindox work?

A: It inhibits bacterial DNA synthesis through quinoxaline dioxide-mediated free radical generation, with preferential activity against Gram-negative bacteria and anaerobic spirochetes such as Brachyspira.

Q4: What is mequindox mainly used for?

A: Its primary indication is swine dysentery (Brachyspira hyodysenteriae). It is also used for bacterial enteritis, piglet yellow/white scour, calf diarrhea, paratyphoid and poultry colibacillosis.

Q5: How is mequindox administered?

A: Orally at 5–10 mg/kg body weight twice daily for 3 days, or by intramuscular injection. It is formulated into premixes, soluble powders and injectable solutions.

Q6: What documents are provided with each batch?

A: Batch-specific COA, HPLC report, IR identity records, melting point data, MSDS/SDS and relevant export documentation are available according to order requirements.

Q7: What purity do you supply?

A: Standard ≥98% HPLC; typical batch result 99%. Higher grades available on request.

Q8: Where can I buy it from China?

A: HDM BIO supplies bulk Mequindox Powder with batch COA and global export support.

Q9: How much does Mequindox Powder cost?

A: Bulk pricing depends on synthesis costs, purity grade, regulatory compliance, order volume and logistics. Contact HDM BIO for a current quotation.

Q10: Is mequindox safe for all uses?

A: Mequindox has been associated with genotoxicity and carcinogenicity in rodent studies. It is supplied as veterinary raw material only, and purchasers must comply with local import, withdrawal-period and use regulations. Not for direct clinical administration.