Rifampin

Athanor · official

C₄₃H₅₈N₄O₁₂ · 822.9 g/mol

IUPAC name: [(7S,9E,11S,12R,13S,14R,15R,16R,17S,18S,19E,21Z)-2,15,17,27,29-pentahydroxy-11-methoxy-3,7,12,14,16,18,22-heptamethyl-26-[(E)-(4-methylpiperazin-1-yl)iminomethyl]-6,23-dioxo-8,30-dioxa-24-azatetracyclo[23.3.1.14,7.05,28]triaconta-1(29),2,4,9,19,21,25,27-octaen-13-yl] acetate

Also called rifampicin, Rifadin, ansamycin, tuberculosis, RNA polymerase inhibitor

Drugs

Open in Athanor

Drawn from its SMILES with RDKit

WarningHarmful if swallowed · Causes skin irritation · Causes serious eye irritation · May cause respiratory irritation

Names and identifiers

IUPAC name: [(7S,9E,11S,12R,13S,14R,15R,16R,17S,18S,19E,21Z)-2,15,17,27,29-pentahydroxy-11-methoxy-3,7,12,14,16,18,22-heptamethyl-26-[(E)-(4-methylpiperazin-1-yl)iminomethyl]-6,23-dioxo-8,30-dioxa-24-azatetracyclo[23.3.1.14,7.05,28]triaconta-1(29),2,4,9,19,21,25,27-octaen-13-yl] acetate
Synonyms: rifampicin, Rifadin, ansamycin
+ 40 more
tuberculosis, RNA polymerase inhibitor, Rifampicin, Rifaldazine, Rifamycin AMP, Rifaprodin, Rifoldin, Rifa, Rifampicinum, Riforal, Abrifam, Eremfat, L-5103 Lepetit, Rifaldin, Rifoldine, R/AMP, Rifampicina, Rifampicine, Ba 41166/E, Rifapiam, BA-41166E, NSC-113926, 3-(((4-Methyl-1-piperazinyl)imino)methyl)rifamycin SV, DTXSID6021244, VJT6J7R4TR, [(7S,9E,11S,12R,13S,14R,15R,16R,17S,18S,19E,21Z)-2,15,17,27,29-pentahydroxy-11-methoxy-3,7,12,14,16,18,22-heptamethyl-26-[(E)-(4-methylpiperazin-1-yl)iminomethyl]-6,23-dioxo-8,30-dioxa-24-azatetracyclo[23.3.1.14,7.05,28]triaconta-1(29),2,4,9,19,21,25,27-octaen-13-yl] acetate, NSC113926, L-5103-LEPETIT, L-5103, NIH-10782, 8-(4-Methylpiperazinyliminomethyl) rifamycin SV, BA-41166/E, 8-(((4-Methyl-1-piperazinyl)imino)methyl)rifamycin SV, Rifomycin SV, 8-(N-(4-methyl-1-piperazinyl)formidoyl)-, CHEBI:28077, 2,7-(Epoxypentadeca(1,11,13)trienimino)naphtho(2,1-b)furan-1,11(2H)-dione, 5,6,9,17,19,21-hexahydroxy-23-methoxy-2,4,12,16,18,20,22-heptamethyl-8-(N-(4-methyl-1-piperazinyl)formimidoyl)-, 21-acetate, Rifampin (Rifampicin), (7S,9E,11S,12R,13S,14R,15R,16R,17S,18S,19E,21Z)-2,15,17,27,29-pentahydroxy-11-methoxy-3,7,12,14,16,18,22-heptamethyl-26-{(E)-[(4-methylpiperazin-1-yl)imino]methyl}-6,23-dioxo-8,30-dioxa-24-azatetracyclo[23.3.1.1(4,7).0(5,28)]triaconta-1(28),1(29),2,4,9,19,21,25,27-nonaen-13-yl acetate, DTXCID301244, 3-([(4-Methyl-1-piperazinyl)imino]methyl)rifamycin SV
Molecular formula: C₄₃H₅₈N₄O₁₂
Empirical formula: C₄₃H₅₈N₄O₁₂
Molecular weight: 822.9 g/mol
Exact mass: 822.40512
CAS number: 13292-46-1
PubChem CID: 135398735
Canonical SMILES: CC1C=CC=C(C(=O)NC2=C(C(=C3C(=C2O)C(=C(C4=C3C(=O)C(O4)(OC=CC(C(C(C(C(C(C1O)C)O)C)OC(=O)C)C)OC)C)C)O)O)C=NN5CCN(CC5)C)C
Isomeric SMILES: C[C@H]1/C=C/C=C(\C(=O)NC2=C(C(=C3C(=C2O)C(=C(C4=C3C(=O)[C@](O4)(O/C=C/[C@@H]([C@H]([C@H]([C@@H]([C@@H]([C@@H]([C@H]1O)C)O)C)OC(=O)C)C)OC)C)C)O)O)/C=N/N5CCN(CC5)C)/C
InChI: InChI=1S/C43H58N4O12/c1-21-12-11-13-22(2)42(55)45-33-28(20-44-47-17-15-46(9)16-18-47)37(52)30-31(38(33)53)36(51)26(6)40-32(30)41(54)43(8,59-40)57-19-14-29(56-10)23(3)39(58-27(7)48)25(5)35(50)24(4)34(21)49/h11-14,19-21,23-25,29,34-35,39,49-53H,15-18H2,1-10H3,(H,45,55)/b12-11+,19-14+,22-13-,44-20+/t21-,23+,24+,25+,29-,34-,35+,39+,43-/m0/s1
InChIKey: JQXXHWHPUNPDRT-WLSIYKJHSA-N
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Physical properties

TemperaturePressureDensity

Appearance: Red-brown crystalline powder[1]
Odor: ODORLESS[1]
Solubility in water: In water, 1,400 mg/L at 25 °C[1]
2 values
From Hazardous Substances Data Bank (HSDB), the most authoritative source here.
Value As written Source
– Freely soluble in chloroform, soluble in ethyl acetate and in methanol. [1] Hazardous Substances Data Bank (HSDB)cites Physicians Desk Reference. Montvale, NJ: Thomson PDR. p. 759 (2003)
–shown In water, 1,400 mg/L at 25 °C [1] Hazardous Substances Data Bank (HSDB)cites Yalkowsky, S.H., He, Yan., Handbook of Aqueous Solubility Data: An Extensive Compilation of Aqueous Solubility Data for Organic Compounds Extracted from the AQUASOL dATAbASE. CRC Press LLC, Boca Raton, FL. 2003., p. 1261
log P: log Kow = 4.24 (estimated)[1]
Vapor pressure: 3.1 × 10⁻³⁴ mmHg at 25 °C (estimated)[1]

Value	As written	Source
–	Freely soluble in chloroform, soluble in ethyl acetate and in methanol.	[1] Hazardous Substances Data Bank (HSDB)cites Physicians Desk Reference. Montvale, NJ: Thomson PDR. p. 759 (2003)
–shown	In water, 1,400 mg/L at 25 °C	[1] Hazardous Substances Data Bank (HSDB)cites Yalkowsky, S.H., He, Yan., Handbook of Aqueous Solubility Data: An Extensive Compilation of Aqueous Solubility Data for Organic Compounds Extracted from the AQUASOL dATAbASE. CRC Press LLC, Boca Raton, FL. 2003., p. 1261

Each value as its source reports it, with the source's number after it (listed under References). Where several sources report a property, the row shows the value most of them agree on, the rule the app uses; open the values to see every one.

Calculated

Heavy atoms: 59
Rings: 5
Aromatic rings: 2
Fraction sp³ carbons (Fsp3): 0.53
H-bond donors: 6
H-bond acceptors: 15
Rotatable bonds: 4 computed here · PubChem 5
TPSA (Å²): 220.1 computed here · PubChem 220
Formal charge: 0
XLogP3: 4.9 PubChem
Complexity: 1620 PubChem
Stereocenters: 9 definedCIP: C3: S · C7: S · C37: S · C39: S · C41: R · C43: R · C45: R · C47: S · C52: R
Double-bond geometry: C4=C5: E · C19=N20: E · C32=C34: Z · C35=C36: E
Point group: C1 of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

C62.76%
H7.10%
N6.81%
O23.33%

Isotope pattern

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P: 4.34 Crippen (Wildman and Crippen 1999)
log S (water solubility): -7.54 ESOL (Delaney 2004), log mol/L
Synthetic accessibility: 7.09 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

Molecular weight ≤ 500: 822.95
log P ≤ 5 (Crippen): 4.34
H-bond donors ≤ 5: 6
H-bond acceptors ≤ 10: 15

Breaks 3 of the four rules.

¹³C NMR shifts, predicted

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

Warning

Most widely reported: 61 company reports to ECHA. Source [2].

Harmful or irritant

H302Harmful if swallowed (98.4% of reports)
H315Causes skin irritation (85.2% of reports)
H319Causes serious eye irritation (85.2% of reports)
H335May cause respiratory irritation (83.6% of reports)

Precautionary statements: P261, P264, P264+P265, P270, P271, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P319, P321, P330, P332+P317, P337+P317, P362+P364, P403+P233, P405, P501

Storage

Rifampin capsules should be stored in tight, light-resistant containers at a temperature of 30 °C or less, preferably between 15-30 °C. The capsules should not be exposed to excessive heat.[1]

Safety data sheets on the supplier’s page: MedChemexpress MCE, Sigma-Aldrich, Alfa Chemistry.

Always read the supplier’s safety data sheet before working with it.

Spectra

Experimental spectra held by these sources; each link opens the source's own record.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

[1]Hazardous Substances Data Bank (HSDB) · Public domain (US NLM) · via PubChem · retrieved 2026-10-14
[2]European Chemicals Agency (ECHA) · ECHA legal notice: reuse with acknowledgement · via PubChem · retrieved 2026-10-14
[3]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
[4]NIST Mass Spectrometry Data Center · Linked only · via PubChem · retrieved 2026-10-14
[5]MassBank Europe · Linked only · via PubChem · retrieved 2026-10-14
[6]MassBank of North America (MoNA) · CC BY 4.0 · via PubChem · retrieved 2026-10-14
·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
·Literature on PubChem

Data last updated 2026-10-14.