Amino Acids

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.

Bis-Boc-guanidinopyrazole

Arginine rich peptides show increased interest during the last years as they have the capability to cross cell and blood brain barrier membranes.

Aspartic and Glutamic Acid Homologues

Arginine rich peptides show increased interest during the last years as the have the capability to cross cell and blood brain barrier membranes.

Thio-Prolines - Rigid Homo-Cys Analogues

Cysteins and homocysteins are found in many natural and artificial peptide sequences. Mercaptoproline is a rigid analogue of homocysteine offering several options to the medicinal chemist.

Bis-Mal-Lysine

Bis Thiol & Amine reactive PEGylated Cross-Linker which has been used for enhanced receptor binding, for the design of long-acting conjugates for type 2 diabetes therapeutics and in reorienting the Fab Domains of Trastuzumab Results in Potent HER2 Activators.

Prolines with Hydrophobic Substituents

Prolines are key elements positioned at the edge of β-turns in peptides. With modified prolines these positions can be used for either covalent amide or disulfide bonds – as we have demonstrated in many examples – or for filling hydrophobic pockets, whenever the pyrrolidine ring is substituted with groups like Methyl or Phenyl.

Product of the Month: Fmoc-L-Cys(Dpm)-OH

Any amino acid can be functionalized on the N-terminus with oxalic acid and on the C-terminus with hydrazine, in order to form a so-called NXO building block. Through this double modification N and C terminus will be inverted, which provides interesting structural options for peptidomimetics.

2-(Fmoc-amino)-3-azidobutanoic acid

Building Blocks for the synthesis of 2,3-diaminobutanoic acid containing peptides or for Click reactions.

N-Fmoc-a-sulfo-b-alanine: a versatile building block for the water solubilisation of chromophores and fluorophores by solid-phase strategy

Abstract: An easy and efficient solid-phase synthesis strategy to obtain rapidly water-soluble chromophores/fluorophores in highly pure form has been developed.

Alpha-Sulfo-beta-Alanine

alpha-Sulfo-beta-Alanine has been used to couple to hydrophobic labels like Cyanine and Rhodamine dyes and other hydrophobic residues to increase their solubility in water. As di- or tripeptide a further increase of hydrophilicity can be achieved. Fmoc-beta-Ala(SO3H)-OH can be coupled in SPPS by standard phosphonium or uronium based coupling reagents. In high throughput technologies for DNA sequencing and genomics charge-modified dye-labeled dideoxynucleoside-5’-triphosphates were synthesized for ‘direct-load’ applications in DNA sequencing.