2-Amino-3-butenoic acid

Overview

2-Amino-3-butenoic acid, also known as dehydroalanine, is an unsaturated amino acid with the chemical formula C4H7NO2. It is a derivative of alanine, where the methyl group is replaced by a vinyl group, resulting in an unsaturated carbon-carbon double bond. This compound is of interest in biochemistry and organic chemistry due to its role as an intermediate in various biochemical pathways and its potential applications in peptide synthesis.

Structure and Properties

2-Amino-3-butenoic acid consists of a carboxyl group (-COOH), an amino group (-NH2), and a vinyl side chain (-CH=CH2) attached to the alpha carbon. The presence of the double bond in the side chain makes it an unsaturated amino acid, which can participate in various chemical reactions, such as Michael additions and cycloadditions.

Chemical Properties

• Molecular Formula: C4H7NO2
• Molar Mass: 101.10 g/mol
• Density: 1.1 g/cm³ (approximate)
• Melting Point: Decomposes before melting
• Solubility: Soluble in water and polar organic solvents

Biological Significance

2-Amino-3-butenoic acid is not one of the standard amino acids found in proteins, but it can be formed as a post-translational modification of cysteine residues in proteins. This modification occurs through the elimination of hydrogen sulfide from cysteine, resulting in the formation of dehydroalanine. This residue can then undergo further reactions, such as cross-linking with other amino acids, which can affect the structure and function of proteins.

Applications in Peptide Synthesis

In synthetic chemistry, 2-amino-3-butenoic acid is used as a building block for the synthesis of peptides and peptidomimetics. Its unsaturated side chain allows for the introduction of various functional groups through addition reactions, making it a versatile intermediate in the design of novel compounds with potential biological activity.

Synthesis

The synthesis of 2-amino-3-butenoic acid can be achieved through several methods, including:

• Dehydrohalogenation of 3-chloroalanine: This involves the elimination of hydrogen chloride from 3-chloroalanine to form the unsaturated amino acid.
• Enzymatic conversion: Certain enzymes can catalyze the conversion of cysteine to dehydroalanine in proteins.

Also see

• Amino acid
• Peptide synthesis
• Post-translational modification
• Cysteine
• Michael addition