Amino Acids

Stable Conjugation with Thiols

Maleimide (MAL) reacts rather specific with free thiol groups and forms appropriate conjugates. However, this reaction is slightly reversible, resulting in loss of the conjugation partner.

Amino functions open the maleimido ring structure through hydrolysis with nucleophilc neighboring effect and thus inhibit the undesired release reaction.

Structural Element: Aminoisobutyric Acid and Homologues

Aminoisobutyric acid (Aib) and its homologues are a strong helix promoters in peptide mimetics. Aib-containing model peptides are already used in cancer treatment, antimicrobial peptides and cell penetrating peptides (CPP).

We offer Aib and its homologues positioning the dimethyl fragment either close to the N- or to the C-terminus.

Polar Amino Acids for Increased Solubilization

alpha-Sulfo-beta-Alanine has been used to couple to hydrophobic molecules and peptides and increase solubility. Attachment can be carried out by conventional Fmoc/tBu protocols.

Custom Synthesis of Alkyne Amino Acids Analogues for Click Conjugation

1,4-substituted 1,2,3-triazole are isosteric to peptide bonds and result in peptide mimetics which even retain activity e.g. in case of certain tyrosinease inhibitors.

We offer custom synthesis of Alkyne Amino Acid Analogues as building blocks for triazol formation via Click conjugation. Side chains can represent all natural amino acids or unusual residues. In combination with our alpha-azido acids we can offer the whole range of building blocks to design Click-peptide bond analogues for every proteinogenic amino acid.

Custom Synthesis of Click-able compounds for Cu-free Click Conjugation

The presence of catalytic copper, limits the in vivo application of the Click this reaction for several reasons.

We offer custom synthesis of Strained Cyclooctynes and Substituted 1,2,4,5- Tetrazines as building blocks for fast Click reactions in the absence of any catalyst.

Custom Synthesis of beta & gamma Amino Acids including Statine Analogues

GABA is a neurotransmitter in the central nervous system of mammals and its deficiency is associated with severe neurological disorders. Statine, a GABA analogue, occurs in several peptide APIs.

Derivatives of gamma-amino acid analogues are of continued vital interest for a variety of applications in medicinal chemistry.

We have a tool box available to offer a broad range of substituted gamma-amino acids and statines on custom synthesis basis.

Benzotriazole Amino Acids

Benzotriazol activated carboxylic acids:

• Fast reaction (within minutes) at room temperature with amines and other nucleophiles under addition of base (in both water and non- aqueous solvents).
• Stable to racemization when coupling with nucleophiles.
• High solubility in organic solvents like DMF and DCM.
• Stable in water.