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Details

Stereochemistry ABSOLUTE
Molecular Formula C25H32N2O3
Molecular Weight 408.5332
Optical Activity UNSPECIFIED
Defined Stereocenters 2 / 2
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of LOFENTANIL

SMILES

CCC(=O)N(C1=CC=CC=C1)[C@@]2(CCN(CCC3=CC=CC=C3)C[C@@H]2C)C(=O)OC

InChI

InChIKey=IMYHGORQCPYVBZ-NBGIEHNGSA-N
InChI=1S/C25H32N2O3/c1-4-23(28)27(22-13-9-6-10-14-22)25(24(29)30-3)16-18-26(19-20(25)2)17-15-21-11-7-5-8-12-21/h5-14,20H,4,15-19H2,1-3H3/t20-,25+/m0/s1

HIDE SMILES / InChI
Molecular Formula C25H32N2O3
Molecular Weight 408.5332
Charge 0
Count
Stereochemistry ABSOLUTE
Additional Stereochemistry No
Defined Stereocenters 2 / 2
E/Z Centers 0
Optical Activity UNSPECIFIED

Description

Lofentanil is a pure mu-opioid receptor agonist derived from fentanyl. It is the most potent opioid to be administered to humans, about 500-1000 times more potent than morphine. Lofentanil provides a higher affinity quotient with longer dissociation times for the mu-receptors than fentanyl. The clinical study of the compound is difficult because there is a very individual sensibility. The appropriate doses are not easy to evaluate. Reversal of the loventanil depression needs very high and repeated naloxone dose. Practical use of lofentanil is limited. Lofentanil side effects are: nausea, vomiting and sedation.

Approval Year

Unknown
149124
PubMed

PubMed

TitleDatePubMed
Ligand-regulated internalization of the opioid receptor-like 1: a confocal study.
2004 Jun
Oral transmucosal fentanyl citrate in cancer pain management: a practical application of nanotechnology.
2007
In vivo mechanisms precipitating torsades de pointes in a canine model of drug-induced long-QT1 syndrome.
2007 Nov 1
The fentanyl/etomidate-anaesthetised beagle (FEAB) dog: a versatile in vivo model in cardiovascular safety research.
2009 Jul-Aug
Patents

Patents

JP2003511351A
27
JP2005520783A
40
JP2005530798A
42
JP2006501241A
15
JP2007507532A
35
JP2011513278A
30
JP4642467B2
32
JP4815084B2
26

Sample Use Guides

In Vivo Use Guide
Single doses: 0.25 ug, 0.50 ug and 0.75 ug
Route of Administration: Intramuscular
Substance Class Chemical
Created
by admin
on Mon Mar 31 18:15:57 GMT 2025
Edited
by admin
on Mon Mar 31 18:15:57 GMT 2025
Record UNII
7H7YQ564XV
Record Status Validated (UNII)
Record Version
  • Download
Name Type Language
LOFENTANIL
INN   MI  
INN  
Official Name English
R-32792
Preferred Name English
4-PIPERIDINECARBOXYLIC ACID, 3-METHYL-4-((1-OXOPROPYL)PHENYLAMINO)-1-(2-PHENYLETHYL)-, METHYL ESTER, CIS, (-)-
Common Name English
LOFENTANIL [MI]
Common Name English
(-)-METHYL CIS-3-METHYL-1-PHENETHYL-4-(N-PHENYLPROPIONAMIDO)ISONIPECOTATE
Common Name English
LOFENTANYL
Common Name English
lofentanil [INN]
Common Name English
Classification Tree Code System Code
NCI_THESAURUS C67413
Created by admin on Mon Mar 31 18:15:57 GMT 2025 , Edited by admin on Mon Mar 31 18:15:57 GMT 2025
WIKIPEDIA List_of_fentanyl_analogues
Created by admin on Mon Mar 31 18:15:57 GMT 2025 , Edited by admin on Mon Mar 31 18:15:57 GMT 2025
Code System Code Type Description
DRUG BANK
DB09174
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PRIMARY
MESH
C034846
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PRIMARY
FDA UNII
7H7YQ564XV
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PRIMARY
INN
4817
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PRIMARY
PUBCHEM
65499
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PRIMARY
WIKIPEDIA
LOFENTANIL
Created by admin on Mon Mar 31 18:15:57 GMT 2025 , Edited by admin on Mon Mar 31 18:15:57 GMT 2025
PRIMARY Lofentanil is one of the most potent opioid analgesics known and is an analogue of fentanyl, which was developed in 1960. It is most similar to the highly potent opioid carfentanil (4-carbomethoxyfentanyl), only slightly more potent. Lofentanil can be described as 3-methylcarfentanil, or 3-methyl-4-carbomethoxyfentanyl. While 3-methylfentanyl is considerably more potent than fentanyl itself, lofentanil is only slightly stronger than carfentanil.(1)(2) This suggests that substitution at both the 3 and 4 positions of the piperidine ring introduces steric hindrance which prevents .MU.-opioid affinity from increasing much further. As with other 3-substituted fentanyl derivatives such as ohmefentanyl, the stereoisomerism of lofentanil is very important, with some stereoisomers being much more potent than
MERCK INDEX
m1205
Created by admin on Mon Mar 31 18:15:57 GMT 2025 , Edited by admin on Mon Mar 31 18:15:57 GMT 2025
PRIMARY Merck Index
WEB RESOURCE
LOFENTANYL
Created by admin on Mon Mar 31 18:15:57 GMT 2025 , Edited by admin on Mon Mar 31 18:15:57 GMT 2025
PRIMARY
EPA CompTox
DTXSID201016402
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PRIMARY
SMS_ID
100000082019
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PRIMARY
EVMPD
SUB08556MIG
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PRIMARY
ChEMBL
CHEMBL28198
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PRIMARY
NCI_THESAURUS
C83890
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PRIMARY
CAS
61380-40-3
Created by admin on Mon Mar 31 18:15:57 GMT 2025 , Edited by admin on Mon Mar 31 18:15:57 GMT 2025
PRIMARY
Related Record Type Details
MU-TYPE OPIOID RECEPTOR
TARGET -> AGONIST
IC50 of Fentanyl= 1.23 NM
IC50
Structure of LOFENTANIL OXALATE
SALT/SOLVATE -> PARENT
Related Record Type Details
Structure of LOFENTANIL
ACTIVE MOIETY
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