Molekula
Erythromycin stearate
Supplying 4,500+ customers in over 80 countries
ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 1999 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need
Erythromycin stearate is the stearic acid salt of erythromycin, a natural macrolide antibiotic produced by fermentation of Saccharopolyspora erythraea, used to treat bacterial infections, particularly in patients allergic to penicillin. It is available as a white to off-white powder with a molecular formula of C37H67NO13·C18H36O2 and a molecular weight of 1018.40 g/mol. It has a CAS number of 643-22-1 and should be stored at 2 to 8 °C. The substance is classified as dangerous.
Molekula supplies Erythromycin stearate at A,B,C >55%, B <12%, C <5% purity in 25 g packs, from £37.08 inc. VAT. It is made or sourced to order. Every batch ships with a certificate of analysis, and safety data sheets are available in 6 languages. Larger quantities, up to multi-tonne, are quoted on request.
Example image for illustration only. Other packaging and pack sizes are available.
Pricing & pack sizes
On backorder — expected to ship by 5 December 2026
These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.
Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.
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25 g — £30.90 per pack ex VAT · £37.08 inc. VAT
Need a different quantity or pack?
Tell us how much you need and when — drums, IBCs, sacks or a one-off bulk lot. We'll manufacture or source it and come back with a price.
Prices exclude VAT/sales tax and shipping.
Specifications
| Property | Value |
|---|---|
| Appearance | White powder |
| Water | ≤4.0% |
| Identification | Conforms to reference |
| Assay | A,B,C >55%, B <12%, C <5% |
| Ethanol | ≤0.5% |
| Residue on Ignition | ≤1.0% |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | 2 to 8 °C |
| Acidity | Acid |
Literature values
Published physical properties of the substance, not batch specifications.
| Property | Value |
|---|---|
| Appearance | Crystals |
| Odour | Practically odorless |
Source: PubChem CID 12559 (HSDB)
Identification
| Property | Value |
|---|---|
| SKU | 32742526 |
| CAS Number | 643-22-1 |
| IUPAC Name | (3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-6-[(2S,3R,4S,6R)-4-(dimethylamino)-3-hydroxy-6-methyloxan-2-yl]oxy-14-ethyl-7,12,13-trihydroxy-4-[(2R,4R,5S,6S)-5-hydroxy-4-methoxy-4,6-dimethyloxan-2-yl]oxy-3,5,7,9,11,13-hexamethyl-oxacyclotetradecane-2,10-dione;octadecanoic acid |
| EC Number | 211-396-1 |
| Molecular Formula | C37H67NO13·C18H36O2 |
| Molecular Weight | 1018.40 |
| Exact Mass | 1017.7328 |
| SMILES | CCCCCCCCCCCCCCCCCC(=O)O.CC[C@@H]1[C@@]([C@@H]([C@H](C(=O)[C@@H](C[C@@]([C@@H]([C@H]([C@@H]([C@H](C(=O)O1)C)O[C@H]2C[C@@]([C@H]([C@@H](O2)C)O)(C)OC)C)O[C@H]3[C@@H]([C@H](C[C@H](O3)C)N(C)C)O)(C)O)C)C)O)(C)O |
| InChIKey | YAVZHCFFUATPRK-YZPBMOCRSA-N |
| InChI | InChI=1S/C37H67NO13.C18H36O2/c1-14-25-37(10,45)30(41)20(4)27(39)18(2)16-35(8,44)32(51-34-28(40)24(38(11)12)15-19(3)47-34)21(5)29(22(6)33(43)49-25)50-26-17-36(9,46-13)31(42)23(7)48-26;1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20/h18-26,28-32,34,40-42,44-45H,14-17H2,1-13H3;2-17H2,1H3,(H,19,20)/t18-,19-,20+,21+,22-,23+,24+,25-,26+,28-,29+,30-,31+,32-,34+,35-,36-,37-;/m1./s1 |
| PubChem CID | 12559 |
| REACH Code | Y110 |
| HTS Code | 29415000 |
| Tariff Code | 2941500000 |
Safety & GHS
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Health Hazard
GHS07
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Serious Health Hazard
GHS08
Hazard statements
- H317 May cause an allergic skin reaction
- H319 Causes serious eye irritation
- H334 May cause allergy or asthma symptoms or breathing difficulties if inhaled
Precautionary statements
- P261 Avoid breathing dust/fume/gas/mist/vapours/spray
- P264 Wash thoroughly after handling
- P280 Wear protective gloves/protective clothing/eye protection/face protection
- P302+352 IF ON SKIN: Wash with soap and water
- P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing
Documents
Safety Data Sheets (SDS)
Available in English, French, German, Italian, Portuguese, Spanish.
Certificate of Analysis (CoA) by batch
Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.
Quality certificates
Molekula Group is certified to ISO 9001:2015 (quality) and ISO 14001:2015 (environmental management), audited by a UKAS-accredited body. Both certificates are valid to 17 May 2028.
Synonyms
- Abboticine
- Bristamycin
- Dowmycin E
- Eratrex
- Erypar
- Erythrocin stearate
- Ethril
- Gallimycin
- Pfizer-E
- Wyamycin S
Frequently asked questions
What is erythromycin stearate used for?
Erythromycin stearate is an antibiotic used to treat bacterial infections, particularly in patients allergic to penicillin.
What is the chemical formula and molecular weight of erythromycin stearate?
The formula is C37H67NO13·C18H36O2 with a molecular weight of 1018.40 g/mol.
How should erythromycin stearate be stored?
Store at 2 to 8 °C; protect from light and moisture.
What grade of erythromycin stearate does Molekula supply?
Molekula supplies erythromycin stearate for research and development, specified for appearance, water content, identification, assay, ethanol and residue on ignition.
Can Molekula supply erythromycin stearate in bulk?
Yes, Molekula can supply erythromycin stearate in bulk quantities—please contact us for pricing and availability.
What documentation comes with an order of erythromycin stearate?
Each order includes a Certificate of Analysis (CoA) and Safety Data Sheet (SDS); additional documentation is available upon request.
Where can I buy Erythromycin stearate?
Directly from Molekula, which lists Erythromycin stearate in 25 g packs from £37.08 inc. VAT, with a certificate of analysis for every batch. Larger quantities are quoted on request. Molekula's offices: United Kingdom, France, Spain, Germany, Italy, United States and China.
Ready to order or need a custom pack?
Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.