Erythromycin Impurity Standards

Erythromycin impurity reference standards are used by pharmaceutical quality-control laboratories, contract research organisations, and generic drug manufacturers to identify, quantify, and control Erythromycin-related impurities during analytical method development, method validation, and regulatory filing. As a macrolide antibiotic, Erythromycin requires precise characterisation of its process impurities, degradation products, and related substances to meet European Pharmacopoeia (EP), United States Pharmacopeia (USP), and British Pharmacopoeia (BP) monograph requirements. Allmpus Laboratories manufactures and supplies a comprehensive library of Erythromycin impurity standards, each provided with a Certificate of Analysis (COA) and Material Safety Data Sheet (MSDS). All products are held in-stock for rapid dispatch and are suitable for use in ANDA and DMF regulatory submissions.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

ERYTHROMYCIN

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-4-[(...

CAS No:
114-07-8

Molecular Formula: C37H67NO13

Molecular Weight: 733.93

CAT No:
ALL-ERY-1194

Keywords: SMILES string - C[C@@H]([C@@H]([C@H](C(O...

Inventory Status:IN STOCK/07-153

COA MSDS

ERYTHROMYCIN A OXIME

Chemical Name: (3R,4S,5S,6R,7R,9R,11S,12R,13S,14R,E)-6-...

CAS No:
111321-02-9

Molecular Formula: C37H68N2O13

Molecular Weight: 748.94

CAT No:
ALL-C03424

Keywords: SMILES string - C[C@H]([C@H]([C@](O)(C[...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN B / 12-DEOXY ERYTHROMYCIN

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12S,13R,14R)-6-{[...

CAS No:
527-75-3

Molecular Formula: C37H67NO12

Molecular Weight: 717.95

CAT No:
ALL-E04246

Keywords: SMILES string - C[C@@H]([C@@H]([C@H](C(...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN C / 3-O-DESMETHYL ERYTHROMYCIN

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-4-((...

CAS No:
1675-02-1

Molecular Formula: C36H65NO13

Molecular Weight: 719.90

CAT No:
ALL-ERY-1196

Keywords: SMILES string - C[C@H]1O[C@@H](O[C@@]([...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY A / ERYTHROMYCIN F

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-4-[(...

CAS No:
82230-93-1

Molecular Formula: C37H67NO14

Molecular Weight: 749.93

CAT No:
ALL-ERY-1197

Keywords: SMILES string - C[C@@]1([H])[C@@](O[C@@...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY B

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-4-[(...

CAS No:
992-62-1

Molecular Formula: C36H65NO13

Molecular Weight: 719.90

CAT No:
ALL-ERY-1198

Keywords: SMILES string - C[C@@H]([C@@H]([C@H](C(...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY C

Chemical Name: (2S,4aR,4?R,5?S,6?S,7R,8S,9R,10R,12R,14R...

CAS No:
41451-91-6

Molecular Formula: C37H65NO14

Molecular Weight: 747.91

CAT No:
ALL-E04250

Keywords: SMILES string - CO[C@](C[C@@]12O[C@]([C...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY D / ANHYDRO ERYTHROMYCIN A

Chemical Name: (1S,2R,3R,4S,5R,8R,9S,10S,11R,12R,14R)-9...

CAS No:
23893-13-2

Molecular Formula: C37H65NO12

Molecular Weight: 715.91

CAT No:
ALL-ERY-1200

Keywords: SMILES string - C[C@H]([C@H]1O)[C@@](O[...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY E / ERYTHROMYCIN A ENOL ETHER

Chemical Name: (2R,3R,4S,5R,8R,9S,10S,11R,12R)-9-[(2,6-...

CAS No:
33396-29-1

Molecular Formula: C37H65NO12

Molecular Weight: 715.92

CAT No:
ALL-E04252

Keywords: Erythromycin Impurity

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY F / PSEUDOERYTHROMYCIN A ENOL ETHER

Chemical Name: (15R,2R,3R,6R,7S,8S,9R)-7-[(2,6-dideoxy-...

CAS No:
105882-69-7

Molecular Formula: C37H65NO12

Molecular Weight: 715.91

CAT No:
ALL-E04253

Keywords: SMILES string - C[C@@](OC([C@@H]([C@]1...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY G / ERYTHROMYCIN ETHYLSUCCINATE IMPURITY G

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-4-[(...

CAS No:
N.A

Molecular Formula: C42H73NO16

Molecular Weight: 848.04

CAT No:
ALL-ERY-1203

Keywords: SMILES string - C[C@@]1(OC)C[C@@](O[C@H...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY H / ERYTHROMYCIN A N-OXIDE

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-4-[(...

CAS No:
992-65-4

Molecular Formula: C37H67NO14

Molecular Weight: 749.93

CAT No:
ALL-ERY-1204

Keywords: SMILES string - C[C@@H]([C@@H]([C@H](C(...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY I

Chemical Name: (1R,4S,5R,8R,9S,10S,11R,12R,14R)-11-(((2...

CAS No:
546-57-6

Molecular Formula: C29H49NO8

Molecular Weight: 539.7

CAT No:
ALL-E04256

Keywords: ERYTHROMYCIN EP IMPURITY I / ERYTHRALOSA...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY J / PSEUDOERYTHROMYCIN A HEMIKETAL

Chemical Name: (1RS,2R,3R,6R,7S,8S,9R,10R,12R)-7-[(2,6-...

CAS No:
105900-46-7

Molecular Formula: C37H67NO13

Molecular Weight: 733.93

CAT No:
ALL-E04257

Keywords: SMILES string - O[C@@H]1[C@](C)(OC)C[C...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY K / ERYTHROMYCIN D

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12S,13R,14R)-4-[(...

CAS No:
33442-56-7

Molecular Formula: C36H65NO12

Molecular Weight: 703.91

CAT No:
ALL-ERY-1207

Keywords: SMILES string - C[C@@H]([C@@H]([C@H](C(...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY L

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12R,13S,14R)-4-[(...

CAS No:
127955-44-6

Molecular Formula: C37H65NO14

Molecular Weight: 747.91

CAT No:
ALL-ERY-1208

Keywords: SMILES string - C[C@@H]([C@@H]([C@H](C(...

Inventory Status:DELIVERY IMMEDIATE

COA MSDS

ERYTHROMYCIN EP IMPURITY M / ERYTHROMYCIN G

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12S,13R,14R)-6-((...

CAS No:
616234-56-1

Molecular Formula: C37H67NO13

Molecular Weight: 733.93

CAT No:
ALL-ERY-1537

Keywords: SMILES string - O=C([C@H](CO)[C@@H](O[C...

Inventory Status:IN STOCK/07-169

COA MSDS

ERYTHROMYCIN EP IMPURITY N

Chemical Name: (3R,4S,5S,6R,7R,9R,11R,12S,13R,14R)-14-e...

CAS No:
3225-82-9

Molecular Formula: C21H38O7

Molecular Weight: 402.53

CAT No:
ALL-E05205

Keywords: SMILES string - O=C1O[C@@H](CC)[C@](C)(...

Inventory Status:IN STOCK/07-168

COA MSDS

Key Erythromycin Impurity Variants Available

Erythromycin EP Impurity A (Erythromycin F / 16 — Hydroxyerythromycin)-a hydroxylated congener formed during fermentation
Erythromycin EP Impurity B (Erythromycin USP Related Compound N / 3″ — N-Desmethylerythromycin A)-an N-demethylation product monitored as a related substance
Erythromycin EP Impurity C — a degradation-related impurity included in the EP related-substances test for Erythromycin
Erythromycin EP Impurity F (Anhydroerythromycin A Enol Ether / Pseudo — Erythromycin A Enol Ether)-a rearrangement product formed under neutral to weakly alkaline conditions, devoid of antibacterial activity
Erythromycin B — a naturally co-produced congener controlled as a related substance alongside Erythromycin A and C

Allmpus Capability for the Erythromycin/Macrolide Family

Allmpus Laboratories manufactures and isolates Erythromycin impurities and related macrolide congeners using preparative isolation and forced-degradation techniques appropriate to the fermentation-derived, multi-congener nature of this API class. Each impurity is supplied with a Certificate of Analysis supported by ¹H NMR, ¹³C NMR, mass spectrometry, HPLC, IR, and TGA data, allowing customers to confirm structural identity and purity for use in stability-indicating method development, method validation, or routine QC testing of Erythromycin base, esters (such as ethylsuccinate and stearate), and salts. Allmpus's macrolide capability spans Erythromycin, Clarithromycin, and Azithromycin impurity families, reflecting shared analytical requirements across this class, including current attention to nitrosamine-related impurities, and is manufactured at its Dombivali, Maharashtra facility for supply to pharmaceutical manufacturers and contract testing laboratories.

Frequently Asked Questions

Are Allmpus Erythromycin impurity standards referenced to EP and USP designations?

Yes. Where a pharmacopeial designation exists, the corresponding EP or USP impurity letter is provided along with the chemical name and any commonly used synonym, to support direct use in monograph-based testing.

What analytical data is provided with each impurity standard?

Each standard is issued with a Certificate of Analysis that includes NMR (¹H and ¹³C), mass spectrometry, HPLC purity, IR, and TGA data to support identity and purity confirmation.

Are these standards suitable for human use?

No. Erythromycin impurity standards are supplied strictly for analytical, research, and reference purposes, including method development and quality control testing, and are not intended for human or veterinary administration.