The compound with the IUPAC systemic description (αS)-α-[(4-morpholinylacetyl)amino]benzenebutanoyl-L-leucyl-L-phenylalanine (CAS Registry Number: 868540-16-3) is a high-purity tripeptide derivative. It is recognized across the pharmaceutical manufacturing sector as a critical key regulatory intermediate used exclusively in the convergent or linear synthesis of Carfilzomib (Trade Name: Kyprolis).

Chemical and Physical Properties

Owing to its specific polypeptide framework, the compound possesses precise physical and chemical traits necessary for robust industrial handling and validation.

• Structural Composition: The compound is comprised of an N-terminal morpholinylacetyl cap, coupled to an (S)-amino-benzenebutanoyl non-proteinogenic amino acid, which is sequentially linked via standard peptide bonds to an L-leucyl-L-phenylalanine dipeptide framework.
• Physical Appearance: Typically a white to off-white crystalline or amorphous solid powder.
• Stereochemical Integrity: The molecule features stringent stereocenters designated by its optical activity (alphaS, L-leucine, L-phenylalanine configurations). Maintaining this exact stereochemistry is vital, as any racemization directly compromises the biological efficacy of the final active pharmaceutical ingredient.
• Solubility Profile: Demonstrates preferential solubility in polar aprotic organic solvents such as Dimethyl Sulfoxide (DMSO), N,N-Dimethylformamide (DMF), and Dichloromethane (DCM). It exhibits limited solubility in water under neutral conditions but can be modulated by adjusting pH due to the tertiary amine on the morpholine ring.

Core Industrial and Laboratory Uses

As a specialized fine chemical, CAS No. 868540-16-3 does not possess a direct consumer use or an independent therapeutic endpoint. Instead, its utility is confined strictly to advanced biochemical manufacturing.The principal industrial application of this compound is its use as the penultimate or primary structural building block for the commercial synthesis of Carfilzomib.In industrial process chemistry, it is coupled with the chiral epoxyketone amine fragment—known chemically as (S)-2-amino-4-methyl-1-((R)-2-methyloxiran-2-yl)pentan-1-one—using specialized peptide coupling reagents to yield the final API.

Product:868540-16-3,Carfilzomib,Kyprolis