Indole turns up in so many places that chemists and product manufacturers hardly ever overlook it. This organic compound forms the backbone for a lot of natural and synthetic substances. Plants churn out indole as a defense, and bacteria create it when breaking down tryptophan. Chemists learned to extract indole from coal tar in the old days, but now most of it comes out of chemical synthesis. The global supply chain keeps the price tight and makes indole available in the purity and physical form industry wants. Indole carries the HS Code 2933999090, so anyone importing or exporting knows where it stands in the international market.
The molecular formula of indole, C8H7N, defines its makeup: eight carbons, seven hydrogens, and a nitrogen atom, all bonded into a two-ring structure. This formula doesn’t look especially complex, but the real magic sits in the chemistry the two rings deliver. Its molecular weight hits about 117.15 g/mol, a compact size for building blocks in the fragrance and pharmaceutical industries. Indole appears as white to slightly yellow crystalline solid at room temperature, often packed and shipped as powder, flakes, or small crystalline lumps. Its density at room temperature sits around 1.22 g/cm3. You’ll pick up a faint, floral scent from it at lower concentrations—think jasmine. If the air gets heavy with indole, the smell turns harsh and almost fecal, making you double-check the storage.
The structure gives away so much about indole’s behavior. It’s got a six-membered benzene ring fused to a five-membered nitrogen-containing pyrrole ring. That makes chemical reactions at the third position especially easy. Manufacturers count on that for quick substitutions without turning the molecule upside down. This dual ring system means you get stability with just enough reactivity to slip into other chemical reactions. Indole won’t dissolve much in water, but it melts easily into organic solvents like ether, ethanol, and benzene. Many suppliers list indole as supplied either as a pure, free-flowing powder or sometimes pressed into pearls or flakes for easy measurement in the plant.
Pharmaceuticals, perfumes, and dyes all put indole to work. Drug makers base whole classes of medicines on the indole backbone. The perfume industry can’t get enough of indole—minute traces in floral scents like jasmine and orange blossom deepen and soften the result. Bulk buyers want indole shipped in secure drums or bags, labeled with molecular formula, CAS number (120-72-9 for those that track), purity (usually topped out at 99% or more), batch number, and hazard symbols. Particle size and form—flake, powder, crystal—matters, especially to factories blending it into other ingredients. The normal melting point lands at approximately 52–54°C. Boiling point reaches up to 254°C under atmospheric pressure. In industrial settings, solubility in liters of solvent per kilogram becomes important, given how much mixing and dissolution goes on at scale. Chemical plants source indole as a raw material because it never sits on shelves as a finished product for long.
Working hands-on with indole means keeping an eye out for hazards. It counts as a harmful chemical in large doses, leading to skin, nose, and throat irritation. Prolonged inhalation of dust or vapors makes respiratory problems more likely. For storage, dry, cool rooms and sealed containers keep indole solid and stop evaporation. No one wants to handle indole without gloves, sealed safety goggles, and proper air extraction above the bench. Indole does not ignite as easily as some organic powders, but dust can still pose explosion risks in poorly ventilated environments. Safety Data Sheets from most suppliers will drill home the need for proper labeling and disposal. It qualifies as a hazardous material under most chemical transport rules. Emergency spills call for quick collection and soft neutralization—never just sweep or flush it away.
Handling challenges grow as volume scales up. Small labs manage with simple containers, but chemical plants deal with tons per month. That means storage solutions have to address both accidental release and potential for environmental contamination. Double-walled drums, ventilated warehouses, and careful tracking of movements have kept incident numbers down. Worker safety calls for more frequent air checks and spill drills in big operations, not just on paper but in daily routines. Supply chains stretch between continents, making purity verification at every step critical, because low-grade or unstable indole can ruin an entire batch downstream. Authenticating Sourcing Certificates and detailed lab analysis remain the main barriers against counterfeiting. Real improvement comes from constant training, tighter safety audits, and digital monitoring of storage environment for temperature and humidity, which both affect product lifespan.
Raw material pricing and availability change the way buyers and sellers close deals. Global demand for pharmaceuticals and synthetic fragrances puts cycles of scarcity and oversupply in play. Price swings send small manufacturers scrambling while big buyers leverage long-term contracts. Tracking indole through the export-import process, each drum ships with HS Codes and customs declarations matching its scientific profile—C8H7N, CAS 120-72-9, hazard class, gross weight, and more. Public data sets show most global indole moves from chemical hubs in China and India, but pricing transparency remains difficult without direct procurement links. Safety regulations now ask for digital manifest records and on-site handling certificates, in part to minimize the risk of unwanted environmental releases during long-distance transport.
Indole shapes daily work for formulators in multiple industries, challenging teams to respect its chemistry and hazards. Using facts on its form, molecular makeup, handling properties, and trade specifications keeps products safe and consistent. Training, robust containers, and regulatory compliance prove just as important as chemical knowledge. Ongoing improvements in monitoring and documentation offer hope for safer, more efficient indole production that lines up with modern chemical standards and the tight demands of international trade.
