MK-777 (Acetamoren)

Description

Overview of MK-777 (Acetamoren)

MK-777 — also identified by the chemical name Acetamoren — is a non-peptide small molecule under early-stage preclinical investigation as a ligand for the growth hormone secretagogue receptor (GHS-R1a, the ghrelin receptor). It is supplied as a research chemical for in vitro receptor binding investigation and preclinical ghrelin-pathway laboratory research.

MK-777 is structurally related to the earlier ghrelin receptor agonist ibutamoren (MK-677) but is a chemically distinct compound. As of 2026, MK-777 has not been the subject of peer-reviewed clinical or preclinical publication. Any receptor-affinity, half-life, or biological-effect claims circulating in vendor marketing materials are not supported by published peer-reviewed research and should not be treated as substantiated.

MK-777 is not a SARM. Despite category placement in some vendor catalogs, MK-777 is a ghrelin receptor agonist, not an androgen receptor modulator. It shares no structural or mechanistic relationship with SARMs.

MK-777 is not approved by the FDA for any therapeutic use. It is not a dietary supplement and is supplied exclusively as a research chemical for in vitro and preclinical laboratory investigation.

Chemical and Molecular Properties

Property	Value
CAS Number	950841-87-9
Molecular Formula	C₂₉H₃₈N₄O₆S (per ChemicalBook CAS entry)
Molecular Weight	570.7 g/mol
IUPAC Name	Propanamide, 2-(acetylamino)-N-[(1R)-2-[1,2-dihydro-1-(methylsulfonyl)spiro[3H-indole-3,4′-piperidin]-1′-yl]-2-oxo-1-[(phenylmethoxy)methyl]ethyl]-2-methyl-
Synonyms	Acetamoren, MK777, MK 777
Purity	≥98% (HPLC verified) — per supplier COA
Physical Form	White to off-white crystalline powder
Solubility	Soluble in DMSO; limited aqueous solubility
Storage	Store at -20°C, protected from light and moisture
Classification	Research Use Only (RUO)

Chemistry note for researchers: Vendor-supplied specifications for MK-777 vary across suppliers, with at least one source listing a fluorinated variant (C₂₈H₃₅FN₄O₅S, MW 558.68). The values above reflect the ChemicalBook reference entry for CAS 950841-87-9. Each PureRawz batch is accompanied by a Certificate of Analysis confirming the specific molecular identity of the shipped material.

Mechanisms Under Investigation

Ghrelin Receptor (GHS-R1a) Binding Research

MK-777 is under investigation in in vitro receptor binding assays as a non-peptide ligand at the growth hormone secretagogue receptor (GHS-R1a). Preclinical receptor-binding assay development and comparative pharmacology against the parent compound class (ibutamoren/MK-677, spiropiperidine GHS-R1a agonists) are the primary research contexts.

Comparative Non-Peptide GHS-R1a Pharmacology

MK-777 is used in laboratory research as a reference compound within the non-peptide spiropiperidine GHS-R1a agonist family, enabling structure-activity relationship investigation and binding-kinetics research in cell-free and cell-culture assay systems.

Research Applications

• In vitro ghrelin receptor (GHS-R1a) binding assay characterization
• Comparative non-peptide GHS-R1a agonist structure-activity research
• Preclinical pharmacology research in ghrelin receptor transfected cell lines
• Reference compound for competitive binding displacement assays
• Analytical chemistry method development for the spiropiperidine chemical series

Quality Assurance

• Certificate of Analysis (COA): Available for every batch — confirms molecular identity and purity
• Third-Party Testing: Independent laboratory verification
• Batch Traceability: Unique lot numbers for every product
• Safety Data Sheet (SDS): Available upon request
• Identity Confirmation: Every batch confirmed against CAS 950841-87-9 reference data

Why Researchers Choose PureRawz

PureRawz supplies MK-777 (Acetamoren) with batch-specific Certificates of Analysis that explicitly confirm molecular identity — a critical parameter for this compound given the variation seen across supplier specifications industry-wide. Each lot is characterized by HPLC retention time and mass spectrometry against the CAS 950841-87-9 reference entry.

Published Research References

Research transparency note: As of April 2026, no peer-reviewed publications specific to MK-777 (Acetamoren) are available. The following references relate to the parent compound class (ibutamoren/MK-677) and the ghrelin receptor pharmacology field that provides context for MK-777 research:

1. Nargund, R.P. et al. "Non-peptidyl growth hormone secretagogues: MK-677 and related spiropiperidine analogs." Merck research laboratory publications on the GHS-R1a agonist chemical series.
2. Nass, R. et al. "Endocrine responses to ghrelin receptor agonists." Hormone Research in Paediatrics. 2008;69(4):257-263 (MK-677 reference).
3. Merck Patent WO 1997/034900 — "Non-peptide growth hormone secretagogues" (parent chemical series).

Multi-Compound Research Note

MK-777 is supplied as a single-compound reference chemical. It is not intended to be combined with SARMs, peptides, or other research compounds. Any such combination is outside the supported use case and not supported by any safety or efficacy data.

Enhanced Disclaimer — GH Secretagogue Class

This product is a research chemical for laboratory use only. NOT approved by the FDA for human use and prohibited for human consumption or injection. Growth hormone is controlled under the Anti-Drug Abuse Act of 1988 and may only be distributed with valid prescription. Compounds that stimulate endogenous growth hormone release, such as ghrelin receptor agonists, carry significantly elevated regulatory exposure and are supplied strictly for in vitro bioassay and preclinical model research only. Unauthorized human use or distribution may violate federal law. Purchaser assumes all liability for federal and state law compliance.

Disclaimer: Preclinical and published research indicates potential mechanisms in laboratory and animal models. References to studies are for informational purposes only and do not constitute claims of human efficacy. Safety and efficacy in humans have not been established. No peer-reviewed human or preclinical efficacy data exists specifically for MK-777 as of April 2026.

ATTENTION: All products are for laboratory research purposes only and not approved for human consumption. Products are not FDA-evaluated and not intended to diagnose, treat, cure, or prevent any disease. Customers assume full responsibility for lawful use per federal, state, and local regulations.