AMIODARONE

Details

Stereochemistry	ACHIRAL
Molecular Formula	C25H29I2NO3
Molecular Weight	645.3116
Optical Activity	NONE
Defined Stereocenters	0 / 0
E/Z Centers	0
Charge	0

SHOW SMILES / InChI

Structure Search

SMILES

CCCCC1=C(C(=O)C2=CC(I)=C(OCCN(CC)CC)C(I)=C2)C3=C(O1)C=CC=C3

InChI

InChIKey=IYIKLHRQXLHMJQ-UHFFFAOYSA-N

InChI=1S/C25H29I2NO3/c1-4-7-11-22-23(18-10-8-9-12-21(18)31-22)24(29)17-15-19(26)25(20(27)16-17)30-14-13-28(5-2)6-3/h8-10,12,15-16H,4-7,11,13-14H2,1-3H3

HIDE SMILES / InChI

Description
Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/022325s002lbl.pdf
Curator's Comment: description was created based on several sources, including: https://www.drugs.com/pro/amiodarone.html | DOI: 10.1007/978-1-4613-2827-8_26

Amiodarone is an antiarrhythmic with mainly class III properties, but it possesses electrophysiologic characteristics of all four Vaughan Williams classes. Like class I drugs, amiodarone blocks sodium channels at rapid pacing frequencies, and like class II drugs, amiodarone exerts a noncompetitive antisympathetic action. In addition to blocking sodium channels, amiodarone blocks myocardial potassium channels, which contributes to slowing of conduction and prolongation of refractoriness. It is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation and hemodynamically unstable ventricular tachycardia in patients refractory to other therapy. The most common adverse reactions (1-2%) leading to discontinuation of intravenous amiodarone therapy are hypotension, asystole/cardiac arrest/pulseless electrical activity, VT, and cardiogenic shock. Other important adverse reactions are, torsade de pointes (TdP), congestive heart failure, and liver function test abnormalities. Fluoroquinolones, macrolide antibiotics, and azoles are known to cause QTc prolongation. There have been reports of QTc prolongation, with or without TdP, in patients taking amiodarone when fluoroquinolones, macrolide antibiotics, or azoles were administered concomitantly. Since amiodarone is a substrate for CYP3A and CYP2C8, drugs/substances that inhibit these isoenzymes may decrease the metabolism and increase serum concentration of amiodarone.

CNS Activity

Originator

Approval Year

Targets

Primary Target	Pharmacology	Potency
Adrenergic receptor beta 87 Target ID: CHEMBL2094118 Sources: Collins, P. (2008) 'Mrcp 1 Pocket', p.84 Retrieved from https://books.google.ru/books?id=FbjdURJT99sC	Inhibitor 8228
HERG 91 Target ID: CHEMBL240 Sources: https://www.ncbi.nlm.nih.gov/pubmed/10208308 \| https://www.ncbi.nlm.nih.gov/pubmed/27256139	Blocker 534	9.8 µM [IC50]
Target ID: Voltage-gated T-type calcium channel (guinea pig) Sources: https://www.ncbi.nlm.nih.gov/pubmed/1281221	Blocker 534
Target ID: Voltage-gated L-type calcium channel (guinea pig) Sources: https://www.ncbi.nlm.nih.gov/pubmed/1281221	Blocker 534
Cytochrome P450 3A 22 Target ID: CHEMBL2364675 Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/022325s002lbl.pdf	Substrate 656
Cytochrome P450 2C8 18 Target ID: CHEMBL3721 Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/022325s002lbl.pdf	Substrate 656

Conditions

Condition	Modality	Targets	Highest Phase	Product
Recurring ventricular fibrillation 2 Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/022325s002lbl.pdf	Primary		Approved 8360	PACERONE Approved Use Amiodarone injection is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in patients refractory to other therapy. Amiodarone also can be used to treat patients with VT/VF for whom oral amiodarone is indicated, but who are unable to take oral medication. During or after treatment with amiodarone, patients may be transferred to oral amiodarone therapy. Launch Date 8.9389439E11
Ventricular tachycardia 11 Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/022325s002lbl.pdf	Primary		Approved 8360	PACERONE Approved Use Amiodarone injection is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in patients refractory to other therapy. Amiodarone also can be used to treat patients with VT/VF for whom oral amiodarone is indicated, but who are unable to take oral medication. During or after treatment with amiodarone, patients may be transferred to oral amiodarone therapy [ see Dosage and Administration (2) Launch Date 8.9389439E11

C_max

Value	Dose	Analyte	Population
23.8 ng/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	2.5 mg/kg single, intravenous dose: 2.5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	DESETHYLAMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
13660 ng/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	5 mg/kg single, intravenous dose: 5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
2920 ng/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	1.25 mg/kg single, intravenous dose: 1.25 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
7140 ng/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	2.5 mg/kg single, intravenous dose: 2.5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
41.2 ng/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	5 mg/kg single, intravenous dose: 5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	DESETHYLAMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
9 ng/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	1.25 mg/kg single, intravenous dose: 1.25 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	DESETHYLAMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
1.7 mg/L EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/6851030/	800 mg single, oral dose: 800 mg route of administration: Oral experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN

AUC

Value	Dose	Analyte	Population
16600 ng × h/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	5 mg/kg single, intravenous dose: 5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
3600 ng × h/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	1.25 mg/kg single, intravenous dose: 1.25 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
8100 ng × h/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	2.5 mg/kg single, intravenous dose: 2.5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
16900 ng × h/mL EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	5 mg/kg single, intravenous dose: 5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	DESETHYLAMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN

T_1/2

Value	Dose	Analyte	Population
14.6 day EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	5 mg/kg single, intravenous dose: 5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
14.2 day EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/21052689/	5 mg/kg single, intravenous dose: 5 mg/kg route of administration: Intravenous experiment type: SINGLE co-administered:	DESETHYLAMIODARONE serum	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: UNKNOWN
4.62 h EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/6851030/	800 mg single, oral dose: 800 mg route of administration: Oral experiment type: SINGLE co-administered:	AMIODARONE serum	Homo sapiens population: UNKNOWN age: UNKNOWN sex: UNKNOWN food status: UNKNOWN

F_unbound

Value	Dose	Co-administered	Analyte	Population
0.023% EXPERIMENT https://pubmed.ncbi.nlm.nih.gov/3242577/	200 mg 1 times / day multiple, oral dose: 200 mg route of administration: Oral experiment type: MULTIPLE co-administered:		AMIODARONE plasma	Homo sapiens population: UNHEALTHY age: ADULT sex: FEMALE / MALE food status: UNKNOWN

Overview

CYP3A4	CYP2C9	CYP2D6	hERG
substrate 1709	inhibitor 1752	substrate 1193 inhibitor 1837	inhibitor 1599

OverviewOther

Other Inhibitor	Other Substrate	Other Inducer
CYP1A2 1509 CYP3A 211 P-gp 1437	CYP2C8 688 CYP1A1 348 CYP1A2 1032 CYP2C19 985

Drug as perpetrator

Target	Modality	Activity	Clinical evidence
CYP2D6 1875	inhibitor 3240 Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613947/; https://pubmed.ncbi.nlm.nih.gov/15541258/	yes [IC50 15 uM]	yes (co-administration study) Comment: reversible inhibition; The area under the plasma concentration-time curve (AUC) of metoprolol increased from 767 before to 1,387 ug * hours/L after the amiodarone loading dose Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613947/; https://pubmed.ncbi.nlm.nih.gov/15541258/
P-gp 1626	inhibitor 3240 Sources: http://www.ncbi.nlm.nih.gov/pubmed/12499648	yes [IC50 5.48 uM]
CYP1A2 1673	inhibitor 3240 Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613947/; https://pubmed.ncbi.nlm.nih.gov/8891878/	yes [IC50 >50 uM]	yes (co-administration study) Comment: reversible inhibition; After treatment with 3 g amiodarone (phase I), this parameter (AUC of lidocaine) increased to 135.3 ± 34.6 (p = 0.016), whereas the AUC of MEGEX decreased from 19.2 ± 6.5 to 15.8 ± 8.3 μg/min/ml (p = 0.04). Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613947/; https://pubmed.ncbi.nlm.nih.gov/8891878/
CYP2C9 1803	inhibitor 3240 Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613947/; https://pubmed.ncbi.nlm.nih.gov/3621782/	yes [IC50 >50 uM]	yes (co-administration study) Comment: reversible inhibition; The mean warfarin AUC during the amiodarone regimen increased to 200% of the control value of anticoagulant alone, from 624 ± 59 Rg/ml-hr to 1249 ± 115 p,g/ml-hr, a significant difference Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613947/; https://pubmed.ncbi.nlm.nih.gov/3621782/
CYP3A 295	inhibitor 3240 Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613947/	yes [IC50 >50 uM]	yes (co-administration study) Comment: reversible inhibition; The mean warfarin AUC during the amiodarone regimen increased to 200% of the control value of anticoagulant alone, from 624 ± 59 Rg/ml-hr to 1249 ± 115 p,g/ml-hr, a significant difference Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4613947/

Drug as victim

Target	Modality	Activity	Clinical evidence
CYP1A1 348	substrate 3326 Sources: https://pubmed.ncbi.nlm.nih.gov/11038157/	yes	likely (co-administration study) Comment: CYP450 inhibitors: grapefruit juice, certain fluoroquinolone and macrolide antibiotics, azole antifungals, cimetidine, certain protease inhibitors: increased exposure of amiodarone. Avoid concomitant use. CYP450 inducers (St. John's Wort): reduced amiodarone serum levels Sources: https://pubmed.ncbi.nlm.nih.gov/11038157/
CYP1A2 1032	substrate 3326 Sources: https://pubmed.ncbi.nlm.nih.gov/11038157/	yes	likely (co-administration study) Comment: CYP450 inhibitors: grapefruit juice, certain fluoroquinolone and macrolide antibiotics, azole antifungals, cimetidine, certain protease inhibitors: increased exposure of amiodarone. Avoid concomitant use. CYP450 inducers (St. John's Wort): reduced amiodarone serum levels Sources: https://pubmed.ncbi.nlm.nih.gov/11038157/
CYP2C19 985	substrate 3326 Sources: https://pubmed.ncbi.nlm.nih.gov/11038157/	yes	likely (co-administration study) Comment: CYP450 inhibitors: grapefruit juice, certain fluoroquinolone and macrolide antibiotics, azole antifungals, cimetidine, certain protease inhibitors: increased exposure of amiodarone. Avoid concomitant use. CYP450 inducers (St. John's Wort): reduced amiodarone serum levels Sources: https://pubmed.ncbi.nlm.nih.gov/11038157/
CYP2C8 688	substrate 3326 Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2008/022325lbl.pdf#page=9; https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/018972s054lbl.pdf#page=6 Page: 9.0	yes	likely (co-administration study) Comment: CYP450 inhibitors: grapefruit juice, certain fluoroquinolone and macrolide antibiotics, azole antifungals, cimetidine, certain protease inhibitors: increased exposure of amiodarone. Avoid concomitant use. CYP450 inducers (St. John's Wort): reduced amiodarone serum levels Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2008/022325lbl.pdf#page=9; https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/018972s054lbl.pdf#page=6 Page: 9.0
CYP2D6 1193	substrate 3326 Sources: https://pubmed.ncbi.nlm.nih.gov/11038157/	yes	likely (co-administration study) Comment: CYP450 inhibitors: grapefruit juice, certain fluoroquinolone and macrolide antibiotics, azole antifungals, cimetidine, certain protease inhibitors: increased exposure of amiodarone. Avoid concomitant use. CYP450 inducers (St. John's Wort): reduced amiodarone serum levels Sources: https://pubmed.ncbi.nlm.nih.gov/11038157/
CYP3A4 1709	substrate 3326 Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2008/022325lbl.pdf#page=9; https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/018972s054lbl.pdf#page=6 Page: 9.0	yes	likely (co-administration study) Comment: CYP450 inhibitors: grapefruit juice, certain fluoroquinolone and macrolide antibiotics, azole antifungals, cimetidine, certain protease inhibitors: increased exposure of amiodarone. Avoid concomitant use. CYP450 inducers (St. John's Wort): reduced amiodarone serum levels Sources: https://www.accessdata.fda.gov/drugsatfda_docs/label/2008/022325lbl.pdf#page=9; https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/018972s054lbl.pdf#page=6 Page: 9.0

Tox targets

Target	Modality	Activity	Metabolite	Clinical evidence
hERG 1632	inhibitor 1613 Sources: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4959829/

Sourcing

Vendor/Aggregator	ID	URL
ChEBI	CHEBI:2663	https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:2663
ChemicalBook	CB5310616	https://www.chemicalbook.com/ChemicalProductProperty_EN_CB5310616
MolPort	MolPort-003-703-670	https://www.molport.com/shop/molecule-link/MolPort-003-703-670
ZINC	ZINC000003830212	http://zinc15.docking.org/substances/ZINC000003830212
eMolecules	901372	https://www.emolecules.com/cgi-bin/more?vid=901372

PubMed

Title	Date	PubMed
Amiodarone-induced depression.	1999 Apr	10533558
Drug-induced torsade de pointes.	1999 Apr 27	10217665
Thyroid hormone alpha1 and beta1 receptor mRNA are downregulated by amiodarone in mouse myocardium.	1999 Aug	10445678
[Severe flecainide acetate poisoning. Apropos of a case].	1999 Feb	10078349
Optic neuropathy following amiodarone therapy.	1999 Jul	10456646
Amiodarone-induced delirium.	1999 Jul	10401472
[Amiodarone-induced bilateral optic atrophy--a case report].	1999 Jun	10412703
[Treatment of cardiac insufficiency: does treatment depend on whether its cause is ischemic or idiopathic?].	1999 Jun	10410811
Reversible fulminant hepatitis following intravenous amiodarone loading. Amiodarone hepatotoxicity.	1999 Jun	10395125
Interaction of amiodarone and triiodothyronine on the expression of beta-adrenoceptors in brown adipose tissue of rat.	1999 Mar	10217540
Inhibitory effects of the class III antiarrhythmic drug amiodarone on cloned HERG potassium channels.	1999 Mar	10208308
[The use of oral amiodarone as a chronic treatment in a patient with prior fulminant hepatitis due to intravenous amiodarone].	1999 Mar	10193175
Features of amiodarone-induced optic neuropathy.	1999 May	10334361
Amiodarone interaction with beta-blockers: analysis of the merged EMIAT (European Myocardial Infarct Amiodarone Trial) and CAMIAT (Canadian Amiodarone Myocardial Infarction Trial) databases. The EMIAT and CAMIAT Investigators.	1999 May 4	10226092
Effects of chronic treatment by amiodarone on transmural heterogeneity of canine ventricular repolarization in vivo: interactions with acute sotalol.	1999 Nov	10690307
Relative effectiveness of the implantable cardioverter-defibrillator and antiarrhythmic drugs in patients with varying degrees of left ventricular dysfunction who have survived malignant ventricular arrhythmias. AVID Investigators. Antiarrhythmics Versus Implantable Defibrillators.	1999 Oct	10520795
[Medication-induced vocal cord paralysis as an uncommon cause of cord paralysis].	1999 Sep	10525613
Meglumine antimoniate, amiodarone and torsades de pointes: a case report.	1999 Sep	10524732
[Toxic hepatitis caused by intravenous amiodarone].	2000 Dec 9	11171458
Oral amiodarone increases the efficacy of direct-current cardioversion in restoration of sinus rhythm in patients with chronic atrial fibrillation.	2000 Jan	10610746
Cardiovascular studies on different classes of soft drugs.	2000 Mar	10756546
Polymorphic ventricular tachycardia after use of intravenous amiodarone for postoperative junctional ectopic tachycardia.	2000 Nov-Dec	11229410
Amiodarone optic neuropathy without disc edema.	2000 Sep	11001193
Amiodarone-related optic neuropathy.	2000 Sep-Oct	11033139
The effects of amiodarone on the thyroid.	2001 Apr	11294826
[Acute papilledema. A 69-year-old patient with acute bilateral papilledema].	2001 Feb	11263051
Anaesthesia for amiodarone-induced thyrotoxicosis: a case review.	2001 Feb	11261905
Inhibitory effects of CYP3A4 substrates and their metabolites on P-glycoprotein-mediated transport.	2001 Feb	11231118
Coronary artery revascularization in patients with sustained ventricular arrhythmias in the chronic phase of a myocardial infarction: effects on the electrophysiologic substrate and outcome.	2001 Feb	11216974
Metabolism of amiodarone (part I): identification of a new hydroxylated metabolite of amiodarone.	2001 Feb	11159805
Bioavailability of amiodarone tablets administered with and without food in healthy subjects.	2001 Feb 15	11179527
Heart rate variability and early recurrence of atrial fibrillation after electrical cardioversion.	2001 Jan	11153731
Amiodarone is safe and highly effective therapy for supraventricular tachycardia in infants.	2001 Jan	11136494
Efficacy of sequential antiarrhythmic treatment in sinus rhythm maintenance after successful electrocardioversion in patients with chronic non-valvular atrial fibrillation.	2001 Jan-Feb	11208496
The role of pharmacologic treatment to prevent sudden death in the implantable cardioverter defibrillator era.	2001 Mar	11177676
[Hyperthyroidism and heart].	2001 Mar 15	11293943
Prenatal diagnosis of junctional ectopic tachycardia.	2001 Mar-Apr	11178678

Patents

Sample Use Guides

In Vivo Use Guide

Intravenous: Initial dose: 1000 mg over the first 24 hours of therapy, delivered by the following infusion regimen: -Loading infusions: 150 mg over the first 10 minutes (15 mg/min), followed by 360 mg over the next 6 hours (1 mg/min) -Maintenance infusion: 540 mg over the remaining 18 hours (0.5 mg/min) Maintenance dose: After the first 24 hours, continue the maintenance infusion rate of 0.5 mg/min; may increase infusion rate to achieve effective arrhythmia suppression. -Supplemental infusions: 150 mg over 10 minutes (15 mg/min) for breakthrough episodes of ventricular fibrillation (VF) or hemodynamically unstable ventricular tachycardia(VT) Maximum dose: Initial infusion rate: 30 mg/min Oral: Loading dose: 800 to 1600 mg orally per day for 1 to 3 weeks (occasionally longer) until adequate arrhythmia control is achieved or if side effects become prominent, then switch to adjustment dose Adjustment dose: 600 to 800 mg orally per day for 1 month, then switch to maintenance dose Maintenance dose: 400 mg orally per day

Route of Administration: Other

In Vitro Use Guide

At concentrations ranging from 75-200 uM, amiodarone induced a significant and dose-dependent release of 51Cr in FRTL-5 cells. In the same molar concentrations, amiodarone was also cytotoxic in CHO cells. In hTF, the release of 51Cr produced by amiodarone occurred at a lower concentration (37.5 vs. 75 uM) and was significantly greater than that in FRTL-5 cells.

Name

Type

Language

AMIODARONE

Official Name

English

AMIODARONE [MI]

Common Name

English

AMIODARONE [VANDF]

Common Name

English

AMIODARONE [USAN]

Common Name

English

AMIODARONE [MART.]

Common Name

English

2-Butyl-3-benzofuranyl 4-[2-(diethylamino)ethoxy]-3,5-diiodophenyl ketone

Systematic Name

English

Amiodarone [WHO-DD]

Common Name

English

amiodarone [INN]

Common Name

English

METHANONE, (2-BUTYL-3-BENZOFURANYL)(4-(2-(DIETHYLAMINO)ETHOXY)-3,5-DIIODOPHENYL)-

Systematic Name

English

Classification Tree Code System Code

NCI_THESAURUS

C47793