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

MedKoo CAT#: 596400

CAS#: 159634-47-6 (free base)

Description: Ibutamoren, also known as MK-677 (L-163,191), is a drug which acts as a potent, orally active growth hormone secretagogue, mimicking the GH stimulating action of the endogenous hormone ghrelin. It has been demonstrated to increase the release of, and produces sustained increases in plasma levels of several hormones including growth hormone and IGF-1, but without affecting cortisol levels.It is currently under development as a potential treatment for reduced levels of these hormones, such as in growth hormone deficient children or elderly adults, and human studies have shown it to increase both muscle mass and bone mineral density, making it a promising therapy for the treatment of frailty in the elderly. It also alters metabolism of body fat and so may have application in the treatment of obesity.

Chemical Structure

CAS# 159634-47-6 (free base)

Theoretical Analysis

MedKoo Cat#: 596400
Name: Ibutamoren
CAS#: 159634-47-6 (free base)
Chemical Formula: C27H36N4O5S
Exact Mass: 528.2406
Molecular Weight: 528.66
Elemental Analysis: C, 61.34; H, 6.86; N, 10.60; O, 15.13; S, 6.06

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.

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Related CAS #: 159752-10-0 (mesylate)   159634-47-6 (free base)    

Synonym: Ibutamoren; L 163191; L-163191; L163191; MK-677; MK 677; MK677;

IUPAC/Chemical Name: (R)-2-amino-N-(3-(benzyloxy)-1-(1-(methylsulfonyl)spiro[indoline-3,4'-piperidin]-1'-yl)-1-oxopropan-2-yl)-2-methylpropanamide


InChi Code: InChI=1S/C27H36N4O5S/c1-26(2,28)25(33)29-22(18-36-17-20-9-5-4-6-10-20)24(32)30-15-13-27(14-16-30)19-31(37(3,34)35)23-12-8-7-11-21(23)27/h4-12,22H,13-19,28H2,1-3H3,(H,29,33)/t22-/m1/s1

SMILES Code: CC(C)(N)C(N[C@H](COCC1=CC=CC=C1)C(N2CCC3(CC2)CN(S(=O)(C)=O)C4=C3C=CC=C4)=O)=O

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

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 528.66 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

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17: Nass R, Pezzoli SS, Oliveri MC, Patrie JT, Harrell FE Jr, Clasey JL, Heymsfield SB, Bach MA, Vance ML, Thorner MO. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults: a randomized trial. Ann Intern Med. 2008 Nov 4;149(9):601-11. PubMed PMID: 18981485; PubMed Central PMCID: PMC2757071.

18: Summaries for patients. Effects of an oral ghrelin mimetic on body composition and clinical outcomes in healthy older adults. Ann Intern Med. 2008 Nov 4;149(9):I-36. PubMed PMID: 18981483.

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