WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 317164

CAS#: 71195-58-9

Description: Alfentanil was discontinued (DEA controlled substance).

Chemical Structure

CAS# 71195-58-9

Theoretical Analysis

MedKoo Cat#: 317164
Name: Alfentanil
CAS#: 71195-58-9
Chemical Formula: C21H32N6O3
Exact Mass: 416.25359
Molecular Weight: 416.53
Elemental Analysis: C, 60.56; H, 7.74; N, 20.18; O, 11.52

Price and Availability

This product is not in stock, which may be available by custom synthesis. For cost-effective reason, minimum order is 1g (price is usually high, lead time is 2~3 months, depending on the technical challenge). Quote less than 1g will not be provided. To request quote, please email to sales or click below button.
Note: Price will be listed if it is available in the future.

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Synonym: ALFENTANIL; Alfentanyl; Alfentanilum; Alfenta; Alfentanilum; Rapifen; R3920; R 39209; R-39209.

IUPAC/Chemical Name: N-[1-[2-(4-ethyl-5-oxotetrazol-1-yl)ethyl]-4-(methoxymethyl)piperidin-4-yl]-N-phenylpropanamide


InChi Code: InChI=1S/C21H32N6O3/c1-4-19(28)27(18-9-7-6-8-10-18)21(17-30-3)11-13-24(14-12-21)15-16-26-20(29)25(5-2)22-23-26/h6-10H,4-5,11-17H2,1-3H3


Appearance: Solid powder

Purity: >98% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: Soluble in DMSO, not in water

Shelf Life: >2 years if stored properly

Drug Formulation: This drug may be formulated in DMSO

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.9001

Preparing Stock Solutions

The following data is based on the product molecular weight 416.53 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

Molarity Calculator

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1: Toman H, Erkılınc A, Kocak T, Guzelmeric F, Savluk OF, Dogukan M, Acar G. Sedation for transesophageal echocardiography: comparison of propofol, midazolam and midazolam-alfentanil combination. Med Glas (Zenica). 2016 Feb 1;13(1). doi: 10.17392/825-16. [Epub ahead of print] PubMed PMID: 26299550.

2: Abou-Arab MH, Feiner JR, Spigset O, Heier T. Alfentanil during rapid sequence induction with thiopental 4 mg/kg and rocuronium 0.6 mg/kg: tracheal intubation conditions. Acta Anaesthesiol Scand. 2015 Nov;59(10):1278-86. doi: 10.1111/aas.12584. Epub 2015 Jul 14. PubMed PMID: 26176994.

3: Türk HŞ, Aydoğmuş M, Ünsal O, Işıl CT, Citgez B, Oba S, Açık ME. Ketamine versus alfentanil combined with propofol for sedation in colonoscopy procedures: a randomized prospective study. Turk J Gastroenterol. 2014 Dec;25(6):644-9. doi: 10.5152/tjg.2014.7014. PubMed PMID: 25599775.

4: Zhao C, Jia N, Wang C, Li Y, Li R, Cui J, Cao S, Wang L, Wu Y, Wen A. Synergistic antinociceptive interactions between fospropofol and alfentanil in mice. Pharmacol Rep. 2015 Feb;67(1):152-9. doi: 10.1016/j.pharep.2014.08.020. Epub 2014 Sep 6. PubMed PMID: 25560590.

5: Sultan SS. Patient-controlled sedation with propofol/remifentanil versus propofol/alfentanil for patients undergoing outpatient colonoscopy, a randomized, controlled double-blind study. Saudi J Anaesth. 2014 Nov;8(Suppl 1):S36-40. doi: 10.4103/1658-354X.144068. PubMed PMID: 25538518; PubMed Central PMCID: PMC4268525.

6: Radke OC, Sippel D, Radke K, Hilgers R, Saur P. Comparison of Two Clinical Protocols for Total Intravenous Anesthesia (TIVA) for Breast Surgery Using Propofol Combined With Either Sufentanil or Alfentanil. Anesth Pain Med. 2014 Sep 3;4(4):e19278. doi: 10.5812/aapm.19278. eCollection 2014 Oct. PubMed PMID: 25337474; PubMed Central PMCID: PMC4199218.

7: Bilgen S, Köner Ö, Karacay S, Sancar NK, Kaspar EC, Sözübir S. Effect of ketamine versus alfentanil following midazolam in preventing emergence agitation in children after sevoflurane anaesthesia: a prospective randomized clinical trial. J Int Med Res. 2014 Dec;42(6):1262-71. doi: 10.1177/0300060514543039. Epub 2014 Sep 12. PubMed PMID: 25217473.

8: Eberl S, Polderman JA, Preckel B, Kalkman CJ, Fockens P, Hollmann MW. Is "really conscious" sedation with solely an opioid an alternative to every day used sedation regimes for colonoscopies in a teaching hospital? Midazolam/fentanyl, propofol/alfentanil, or alfentanil only for colonoscopy: a randomized trial. Tech Coloproctol. 2014 Aug;18(8):745-52. doi: 10.1007/s10151-014-1188-y. Epub 2014 Jun 29. PubMed PMID: 24973875.

9: Razavi S, Gharaei B, Jafari A, Aghamohammadi H, Mirkheshti A. Propofol and alfentanil in treatment of a patient with episodic cluster headache. Anesth Pain Med. 2014 May 3;4(2):e17560. doi: 10.5812/aapm.17560. eCollection 2014 May. PubMed PMID: 24910816; PubMed Central PMCID: PMC4030261.

10: Jaime C, Virgili A, Portillo S, Caparrós A, Burusco KK. Configuration and conformation of alfentanil hydrochloride. Conformational study by NMR and theoretical calculations. Magn Reson Chem. 2014 Aug;52(8):440-7. doi: 10.1002/mrc.4085. Epub 2014 Jun 3. PubMed PMID: 24889875.

Additional Information

Alfentanil has a pKa of approximately 6.5, which leads to a very high proportion of the drug being uncharged at physiologic pH. This unique characteristic is responsible for its rapid onset. It is an agonist at mu opioid receptors. While alfentanil tends to cause fewer cardiovascular complications than other similar drugs such as fentanyl and remifentanil, it tends to give stronger respiratory depression and so requires careful monitoring of breathing and vital signs. Almost exclusively used by anesthesia providers during portions of a case where quick, fast acting (though not long lasting) pain control is needed (i.e. during a nerve block, head pinning etc..) Alfentanil is administered by the parenteral (injected) route for fast onset of effects and precise control of dosage. Alfentanil is a restricted drug which is classified as Schedule II in the USA, according to the U.S. DEA website.