U-50488 Free Base

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MedKoo CAT#: 414392

CAS#: 67198-13-4 (free base)

Description: U-50488 Free Base is a non-peptide, kappa-opioid receptor agonist which has also been found to stimulate the release of adrenocorticotropin (ADRENOCORTICOTROPIC HORMONE) via the release of hypothalamic arginine vasopressin (ARGININE VASOPRESSIN) and CORTICOTROPIN-RELEASING HORMONE.

Chemical Structure

U-50488 Free Base
CAS# 67198-13-4 (free base)

Theoretical Analysis

MedKoo Cat#: 414392
Name: U-50488 Free Base
CAS#: 67198-13-4 (free base)
Chemical Formula: C19H26Cl2N2O
Exact Mass: 368.14
Molecular Weight: 369.330
Elemental Analysis: C, 61.79; H, 7.10; Cl, 19.20; N, 7.59; O, 4.33

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 @medkoo.com or click below button.
Note: Price will be listed if it is available in the future.

Related CAS #: 67197-96-0 (racemic HCl)   114528-79-9 ((-)-U-50488 HCl)   67198-13-4 (free base),  

Synonym: U-50488 Free Base; U50488; U 50488; UM1382; UM-1382; UM 1382

IUPAC/Chemical Name: Benzeneacetamide, 3,4-dichloro-N-methyl-N-(2-(1-pyrrolidinyl)cyclohexyl)-, trans-


InChi Code: InChI=1S/C19H26Cl2N2O/c1-22(19(24)13-14-8-9-15(20)16(21)12-14)17-6-2-3-7-18(17)23-10-4-5-11-23/h8-9,12,17-18H,2-7,10-11,13H2,1H3/t17-,18-/m1/s1

SMILES Code: O=C(N(C)[C@H]1[C@H](N2CCCC2)CCCC1)CC3=CC=C(Cl)C(Cl)=C3

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: To be determined

Shelf Life: >2 years if stored properly

Drug Formulation: To be determined

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

More Info:

Biological target:
In vitro activity:
In vivo activity:

Preparing Stock Solutions

The following data is based on the product molecular weight 369.33 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
Formulation protocol:
In vitro protocol:
In vivo protocol:

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3: Russell SE, Rachlin AB, Smith KL, Muschamp J, Berry L, Zhao Z, Chartoff EH. Sex differences in sensitivity to the depressive-like effects of the kappa opioid receptor agonist U-50488 in rats. Biol Psychiatry. 2014 Aug 1;76(3):213-22. doi: 10.1016/j.biopsych.2013.07.042. Epub 2013 Oct 3. PMID: 24090794; PMCID: PMC4476271.

4: Hassan B, Ruiz-Velasco V. The κ-opioid receptor agonist U-50488 blocks Ca2+ channels in a voltage- and G protein-independent manner in sensory neurons. Reg Anesth Pain Med. 2013 Jan-Feb;38(1):21-7. doi: 10.1097/AAP.0b013e318274a8a1. PMID: 23222359; PMCID: PMC3530143.

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15: Jang CG, Lee SY, Park Y, Ma T, Loh HH, Ho IK. Differential effects of morphine, DPDPE, and U-50488 on apomorphine-induced climbing behavior in mu- opioid receptor knockout mice. Brain Res Mol Brain Res. 2001 Oct 19;94(1-2):197-9. doi: 10.1016/s0169-328x(01)00227-3. PMID: 11597780.

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