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R9904

Sigma-Aldrich

Rifaximin

Synonym(s):

4-Deoxy-4′-methylpyrido[1′,2′-1,2]imidazo[5,4-c]rifamycin SV, Rifacol

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About This Item

Empirical Formula (Hill Notation):
C43H51N3O11
CAS Number:
80621-81-4
Molecular Weight:
785.88
MDL number:
MFCD00864973
UNSPSC Code:
51283604
PubChem Substance ID:
329824049
NACRES:
NA.85

form

powder

storage condition

(Keep container tightly closed in a dry and well-ventilated place.)

color

red to orange

antibiotic activity spectrum

Gram-negative bacteria
Gram-positive bacteria

Mode of action

protein synthesis | interferes

storage temp.

2-8°C

SMILES string

CO[C@H]1\C=C\O[C@@]2(C)Oc3c(C)c(O)c4c(O)c(NC(=O)C(C)=C\C=C\[C@@H](C)[C@@H](O)[C@@H](C)[C@H](O)[C@H](C)[C@H]([C@H]1C)C(=O)OC)c5c(nc6cc(C)ccn56)c4c3C2=O

InChI

1S/C43H51N3O11/c1-19-14-16-46-27(18-19)44-32-29-30-37(49)25(7)39-31(29)40(51)43(8,57-39)56-17-15-26(54-9)22(4)28(42(53)55-10)23(5)36(48)24(6)35(47)20(2)12-11-13-21(3)41(52)45-33(34(32)46)38(30)50/h11-18,20,22-24,26,28,35-36,47-50H,1-10H3,(H,45,52)/b12-11+,17-15+,21-13-/t20-,22+,23-,24-,26+,28+,35-,36-,43+/m1/s1

InChI key

HIYLTQREEOINNF-HTEWPBCCSA-N

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General description

Chemical structure: macrolide

Application

Rifaximin is a semisynthetic analog of rifamycin with poor absorptivity. It selectively inhibits (E. coli, B subtilis) bacterial DNA-dependent RNA polymerase by a mechanism similar to rifabutin, β subunit binding. It is effective against aerobic and anaerobic Gram-positive and Gram-negative bacteria. It is active against species of Staphylococcus, Streptococcus and Enterococcus. It is less active against species of Enterobacteriaceae. Rifaximin is a non-systemic, gastrointestinal site-specific antibiotic. It has a pyridoimidazole ring, making it non-absorbable. Rifaximin is a pregnane X receptor (PXR) activator.

Biochem/physiol Actions

Rifaximin is a semisynthetic analog of rifamycin with poor absorptivity. Mode of action: selectively inhibits (E. coli, B subtilis) bacterial DNA-dependent RNA polymerase by mechanism similar to rifabutin, β subunit binding.
Antimicrobial spectrum: Aerobic and anaerobic Gram-positive and Gram-negative bacteria. Active against species of Staphylococcus, Streptococcus and Enterococcus; less active against species of Enterobacteriaceae.†

Preparation Note

Practically insoluble in water, soluble in acetone and methanol.

Other Notes

Keep container tightly closed in a dry and well-ventilated place.

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

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Marina Ferrer et al.
International journal of molecular sciences, 22(2) (2021-01-10)
Rifaximin is a broad-spectrum antibiotic that ameliorates symptomatology in inflammatory/functional gastrointestinal disorders. We assessed changes in gut commensal microbiota (GCM) and Toll-like receptors (TLRs) associated to rifaximin treatment in mice. Adult C57BL/6NCrl mice were treated (7/14 days) with rifaximin (50/150
Jiannis Vlachogiannakos et al.
Journal of gastroenterology and hepatology, 28(3), 450-455 (2012-12-12)
Cirrhotic patients are predisposed to intestinal bacterial overgrowth with translocation of bacterial products which may deteriorate liver hemodynamics. Having shown that short-term administration of rifaximin improves liver hemodynamics in decompensated cirrhosis, we conducted this study to investigate the effect of
J C Gillis et al.
Drugs, 49(3), 467-484 (1995-03-01)
Rifaximin is a derivative of rifamycin which acts by inhibiting bacterial ribonucleic acid (RNA) synthesis. It is virtually unabsorbed after oral administration; thus it is used primarily to treat local conditions within the gastrointestinal tract. In vitro data indicate rifaximin
E Mattila et al.
Alimentary pharmacology & therapeutics, 37(1), 122-128 (2012-10-26)
Clostridium difficile can cause severe antibiotic-associated colitis. Conventional treatments with metronidazole and vancomycin improve symptoms, but after discontinuation of treatment, C. difficile infection (CDI) recurs in a number of patients. Rifaximin is a rifamycin-based non-systemic antibiotic that has effect against
Vishesh Kothary et al.
Antimicrobial agents and chemotherapy, 57(2), 811-817 (2012-11-28)
Escherichia coli is implicated in the pathogenesis of inflammatory bowel disease (IBD). Rifaximin, a nonabsorbable derivative of rifampin effective against E. coli, improves symptoms in mild-to-moderate IBD. However, rifaximin resistance can develop in a single step in vitro. We examined
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