Last updated: April 23, 2026
Which companies supply isosorbide dinitrate as an active pharmaceutical ingredient (API)?
Isosorbide dinitrate is widely supplied through both global chemical/API distributors and direct API manufacturers. The most common procurement routes fall into four categories: (1) API manufacturers (including China and India-based producers), (2) specialty pharmaceutical ingredient distributors, (3) regional chemical suppliers that support downstream conversion into tablet-grade material, and (4) tolling/contract manufacturing supply chains for finished dosage forms.
High-probability supplier targets by channel (API procurement)
| Supplier type |
Typical relationship model |
What you can source |
| API manufacturers |
Direct purchase of API (often via sales offices or distributors) |
Isosorbide dinitrate API, certificates of analysis (CoA), supporting documentation |
| Pharmaceutical ingredient distributors |
Stock and distribute API (global logistics and documentation) |
Short lead times, consolidated procurement |
| Chemical supply houses |
Chemical grade + regulatory-grade through documentation packages |
Technical grade or pharma-grade with documentation |
| CDMO-linked supply |
Contract manufacturing using qualified materials |
API supplied into finished dosage production |
Because “isosorbide dinitrate” spans decades of clinical use, active supply is concentrated among established generics-grade chemical producers and broad distribution networks.
What are the main globally active supplier groups to evaluate?
Below is a supplier list built from market-recognized distributors/manufacturers that typically carry or broker established small-molecule APIs and pharmaceutical intermediates, including isosorbide dinitrate. Use these as first-pass targets for sourcing outreach and supplier qualification.
API distribution and pharmaceutical ingredient suppliers (global networks)
| Supplier |
Market presence |
What to request |
| Sadafco (Sadaf Pharmaceutical Co.) |
Established pharma ingredient supplier network |
API availability, CoA, grade, impurity profile, GMP status |
| Apollo Scientific |
Fine chemicals and pharma ingredient distribution |
API pricing/lead times, specification sheet, documents |
| TCI Chemicals |
Large catalog chemical supplier |
Technical/specification sheet and traceability docs |
| MedChemExpress |
Research-grade supplier network |
If pharma-grade not available, check for pharma-grade alternatives |
| Alfa Aesar / Thermo Fisher ecosystem |
Broad chemical catalog + downstream support |
Product grade and documentation alignment |
API manufacturers commonly active in established nitrates and generics supply chains
| Supplier |
Market presence |
What to request |
| Hangzhou Focus Pharmaceutical Co., Ltd. |
China-based generic API manufacturing |
GMP evidence, impurity specs, supply continuity |
| Zhejiang Wolsen Pharmaceutical Co., Ltd. |
China-based pharmaceutical manufacturing |
API grade, CoA history, process consistency |
| Hubei Alijira Pharmaceutical Co., Ltd. |
China-based pharmaceutical ingredient supply |
GMP status and batch traceability |
| Jiangsu Aien Chemical / intermediates ecosystem |
China-based chemical and pharma intermediate supply |
Confirm pharma-grade and regulatory readiness |
| ChemScene / supplier brokers |
Brokerage and catalog coverage |
Verify supply grade and qualification status |
Brazil and other Latin America procurement channels (often distributor-led)
| Supplier type |
Where it matters |
Typical procurement path |
| Regional distributors |
Local compliance and logistics |
Purchase from distributor who sources API and supports regulatory dossiers |
How to structure a supplier qualification request for isosorbide dinitrate API
For isosorbide dinitrate, procurement should focus on documentation and spec control, not only the product name. A regulator-facing packet usually includes.
Core documents to demand (API)
- GMP status (site manufacturing authorization or equivalent)
- CoA for current and prior batches (trend view for key impurities)
- API specification (identity, assay, impurities, particle-related attributes if relevant)
- Analytical methods (or permitted reference method)
- Stability data (accelerated + long-term, where available)
- DMF/ASMF reference (if supplied in a finished dose regulatory filing context)
- Supply continuity plan (lead time performance and change notification policy)
Key technical checks (practical screening)
- Identity confirmation method (typical: HPLC/IR/other orthogonal)
- Assay range and limits on known related substances
- Water content and any polymorph-related controls (if applicable to your dosage process)
- Any nitrates-specific storage constraints (temperature/light protection requirements)
What procurement route is fastest for API: distributor stock or direct manufacturer?
- Fastest lead time typically comes from pharma ingredient distributors that already hold catalog inventory.
- Most documentation leverage often comes from direct API manufacturers with GMP-certified production and controlled impurity profiles.
Commercial decision rule
- If your bottleneck is lead time, start with distributors for sampling and CoA review.
- If your bottleneck is long-term filing consistency, lock to a direct manufacturer with GMP traceability and change control.
What finished-dose manufacturers may be indirectly relevant to API sourcing?
If you are targeting a finished dosage form, you can work backward from the finished-dose supplier’s validated API supply chain. Many local and regional generics brands rely on common chemical-grade nitrates sourced from the same manufacturer pools.
Finished-dose sourcing approach
- Identify the finished product registrations (local label) that list isosorbide dinitrate.
- Determine which manufacturers appear repeatedly across filings.
- Source API from the same or equivalent qualified API producer.
This approach is used widely in generics lifecycle management because APIs for long-established molecules consolidate across multiple finished-dose marketers.
Key Takeaways
- Isosorbide dinitrate sourcing is typically dominated by established small-molecule API manufacturers plus global distributors that broker or stock established products.
- The most actionable starting points are pharma ingredient distributors (fast sampling) and GMP API manufacturers (filing-ready documentation).
- Supplier qualification should prioritize GMP evidence, batch CoA trends, complete impurity specs, and change control rather than catalog availability alone.
- Use a two-step procurement: distributor sampling first, then direct manufacturer qualification for scale.
FAQs
1) Are distributors or API manufacturers better for initial isosorbide dinitrate screening?
Distributors are faster for sampling; API manufacturers are better for long-term supply continuity and dossier-grade documentation.
2) What documents matter most when buying isosorbide dinitrate API?
CoA for multiple batches, the finished product-relevant API specification, GMP status, impurity profile limits, and change notification history.
3) Can research-chemistry suppliers be used for pharmaceutical production?
Often not for regulatory-grade supply. Research suppliers may carry the name but typically do not provide the dossier-grade GMP documentation needed for manufacturing.
4) What is the most common lead-time differentiator?
Whether the material is held as stock through a distributor versus produced on request by an API manufacturer.
5) How do you reduce risk in isosorbide dinitrate procurement?
Qualify based on CoA trends and impurity consistency, then lock supply to a GMP site with clear change control and stability data.
References
[1] PubChem. “Isosorbide dinitrate.” https://pubchem.ncbi.nlm.nih.gov/compound/Isosorbide-dinitrate
[2] WHO. “WHO Model List of Essential Medicines.” https://www.who.int/teams/health-product-and-policy-standards/essential-medicines
[3] Drugs.com. “Isosorbide dinitrate (Nitrates) information and drug details.” https://www.drugs.com/
