Rifaximin

Description

Rifaximin · CAS 80621-81-4 · C43H51N3O11. UNII L36O5T016N. LogP: 2.6.

Identification

CAS Registry Number	80621-81-4
PubChem CID	6436173
Molecular formula	C43H51N3O11
IUPAC name	[(7S,9E,11S,12R,13S,14R,15R,16R,17S,18S,19E,21Z)-2,15,17,36-tetrahydroxy-11-methoxy-3,7,12,14,16,18,22,30-octamethyl-6,23-dioxo-8,37-dioxa-24,27,33-triazahexacyclo[23.10.1.14,7.05,35.026,34.027,32]heptatriaconta-1(35),2,4,9,19,21,25(36),26(34),28,30,32-undecaen-13-yl] acetate
UNII (FDA)	L36O5T016N

Computed Descriptors

Molecular Weight	785.9
XLogP3	6.9
Hydrogen Bond Donor Count	5
Hydrogen Bond Acceptor Count	12
Rotatable Bond Count	3
Exact Mass	785.35235945
Monoisotopic Mass	785.35235945
Topological Polar Surface Area	198
Heavy Atom Count	57
Formal Charge	0

Physical & Chemical Properties

LogP	2.6

Physical description & handling notes

• 267.74 Ų [M+H]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]
• 263.95 Ų [M+K]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]
• 270.84 Ų [M+Na]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]
• 267.8 Ų [M+H]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]

Regulatory Status

GHS notification summary	22.2% (4 / 18)

GHS Hazard Classification

GHS notification summary	22.2% (4 / 18)
Reported hazard statements	H312 (55.6%), H332 (55.6%), H335 (55.6%), H361 (22.2%)

Documented Uses

• Use (kg; approx.) in Germany (2009): >25
• Consumption (g per capita; approx.) in Germany (2009): 0.000305
• Rifaximin has multiple indications by the FDA: for the treatment of patients (≥12 years of age) with traveller's diarrhea caused by noninvasive strains of Escherichia coli; for the reduction of overt hepatic encephalopathy recurrence in patients ≥18 years of age; and in May 2015 it was approved for irritable bowel syndrome with diarrhea (IBS-D) treatment in adult men and women.
• Rifaximin is a nonabsorbable oral antibiotic. Rifaximin has a broad spectrum of activity against both gram-negative and gram-positive anaerobic and aerobic bacteria. This antibiotic is used primarily for gastrointestinal and liver diseases since it is specific to the gastroenterology tract due to its nonabsorbable profile. Rifaximin was first approved in the United States in 2004 but has been in use since 1987, when it first received approval in Italy.
• Rifaximin is a nonabsorbable antibiotic that is used as treatment and prevention of travelers’ diarrhea and, in higher doses, for prevention of hepatic encephalopathy in patients with advanced liver disease and to treat diarrhea in patients with irritable bowel syndrome. Rifaximin has minimal oral absorption and has not been implicated in causing liver test abnormalities or clinically apparent liver injury.
• Breast Feeding; Lactation; Milk, Human; Anti-Infective Agents; Gastrointestinal Agents; Rifamycins

Synonyms

Rifaximin; 80621-81-4; Rifaxidin; Rifacol; Xifaxan; Rifamycin L 105; Rifaximine; Rifaximina; Normix; Rifamycin L 105SV; Rifaximinum; Xifaxsan; L-105; Xifaxanta; DTXSID7045998; L36O5T016N

Frequently Asked Questions

What are the CAS number and molecular formula of Rifaximin?

CAS 80621-81-4; molecular formula C43H51N3O11; molecular weight — g/mol.

What other names is Rifaximin known by?

Rifaximin, 80621-81-4, Rifaxidin, Rifacol, Xifaxan, Rifamycin L 105.

Is Rifaximin classified as hazardous?

22.2% of GHS notifications report no hazard classification (4 of 18).

What are the key physical properties of Rifaximin?

LogP: 2.6.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.