Search results for: 'psi'

GGFG Motif for ADC Construction

To address both chemical and IP considerations in self-immolating linker applications , we propose shifting from the commonly used Val-Cit-PAB linker to the less explored Gly-Gly-Phe-Gly-formyl motif.

Linkerology® for Targeted Delivery and Release

Use the possibilities of Linkerology® to boost the efficacy of your drug! We illustrate how the drug Gepirone (Exxua TM ), a medication to treat major depressive disorders, can be conjugated.

PotM: Oligomeric Sarcosine Building Blocks

You are looking for monodisperse Sarcosines ? You want to use Sarcosine for SPPS? You need to improve your drug's hydrophilicity and search for PEG alternatives? Read on!

Linkerology® - An Example of Advanced Conjugation

The targeted delivery and traceless release of drugs is an important concept in pharmacology. Discover the possibilities of payload conjugation to carrier proteins shown for the example drug Elacestrant.

Combination Therapy & Linkerology®

Discover possibilities to fight chronic pain diseases by employing linker technologies. Check out the options for multiple drug conjugation in combination with different release mechanisms.

Selective Lysine Labeling with Squaric Acid

Keeping control! PEGylating reagents with a squaric acid ethyl ester react chemoselectively with side chain amino functions of surface-accessible Lysines in proteins. Other functionalities are not affected.

Conjugating Small Molecule Drugs

You want to attach your small molecule to a certain carrier? Let’s analyze the functional groups present and discuss Linkerology® possibilities for permanent or trigger-inducible, tracelessly-cleavable linkage.

Carbamidomethylated Cysteine as SPPS Building Block

Our building block Fmoc-L-Cys(Cam)-OH enables peptides resembling reduced and carbamido-methylated protein fragments by standard SPPS without error-prone modification reactions.

Fluorogenic Protease Substrates with Enhanced Signal-to-Noise-Ratio

Shine bright like our fluorophores! Learn how our superior fluorogenic protease substrate peptides can enhance your test performance. Click here to gather more information and discover available products!

Fatty Di-Acids

Peptide therapeutics – fewer injections/lower doses by prolonging their half-life via addition of a lipid modification that promotes binding to serum proteins such as albumin. Read on for recent innovations!

Conjugating Natural Products (1)

From evolution to solution - natural products are an infinite source of (bio)active compounds. In this series we present how natural products can be conjugated to empower their inherent potential.

Amino-PEG-Acids

PEGs are being used as spacers, as hydrophilic decoration, and building blocks. Read on for more detailed information about the reactivity of different PEG derivatives and how to use them.

Temporary Activity Masking via Self-Immolative Linkage

(Bi)functional dioxoborolane and disulfide-based self-immolative linkers – mode of action and application examples for the detection of H 2 O 2 , for prodrug design, and reversible peptide cyclization.

Acylation Efficiencies on Ser and Thr Pseudoproline Monomers

In two joint studies together with Prof. F. Albericio we investigated the coupling efficiencies of Ser and Thr pseudoproline monomers and their use for the synthesis of inaccessible peptide sequenes. Read on!

PotM: His Tags for the Chemical Modification of Peptides

Jensen et al. developed two methods that use poly-His sequences to direct the highly selective acylation of proteins, either at the N-terminus or at a specific Lys residue. Read on for more information.

Linker Technologies for Sophisticated Bioconjugations

Linkers serve as versatile tools, e.g. during SPPS or for the sophisticated (self-immolative) conjugation of a potent small molecule to a carrier. Check out our selection of over 100 readily available linkers.

The Dawson Linker

The Dawson Linker and its variants provide access to C-terminal peptide thioesters which are crucial components of Native Chemical Ligation reactions. Read on to discover all derivatives available at Iris Biotech!

Dyes and Fluorescent Labels at Iris Biotech

Dyes and fluorescent labels are an invaluable tool for diagnostics, medical and biochemical research. Iris Biotech offers labels with excitation ranges from UV to near-IR and various functional groups.

Amino Acid Oxidation Products

Oxidation is not only a known degradation pathway of proteins and peptides in vivo but is also a major side reaction for certain amino acids during peptide synthesis in vitro. Read on to discover our available building blocks.

iNoc – An Acid Stable Alternative to Cbz

Looking for an acid stable protecting group? Struggling with undesired loss of the Cbz protecting group while removing Boc under acidic conditions? Read on to find out more about iNoc as alternative.

Protease Stable Ile/Leu Surrogates

Herein we are presenting 2-(Fmoc-amino)-3,3-diMe-pent-4-enoic acid (FAA5040), a protease stable Ile/Leu surrogate suitable for further modification via its side chain double bond.

Enzymatically Cleavable Linkers Based on Val-Cit and Val-Ala

The peptide-based ADC linkers Val-Cit and Val-Ala are efficiently cleaved by lysosomal proteases and benefit from increased serum stability and effective payload-release in targeted cells.

Fmoc-L-Cys(Palm)-OH – A S-palmitoylated Cysteine building block

Interested in studying the effect of palmitoylation on your peptide’s localization, function, and stability? Read on to find out more about the use of lipidated “fatty” amino acids!

Fmoc-MeDbz-OH – Available on Large Scale

Are you using the Fmoc-MeDbz-OH Dawson Linker in large scale on a regular basis? A robust and economic processallows us to promptly provide you with kg quantities at competitive prices and in high quality.

New Dawson Linker Derivatives

Interested in the formation of peptide thioesters for Native Chemical Ligation? Read on to find out more about the use of Dawson Linker derivatives as thioester surrogates compatible with Fmoc SPPS.

Amino-Methylcoumarins as Fluorescent Labels

Enzymatically-activatable probes based on 7-amino-4-methylcoumarin (AMC) represent versatile tools for the detection and localization of proteolytic enzyme activities. Read on to find out more.

Valine-Citrulline Based Enzymatically Cleavable Linkers

Iris Biotech presents its selection of Val-Cit-based linkers, a dipeptide motif frequently utilized for the development of ADCs with increased serum stability and high cleavage efficiency.

His-Tag for Specific Linker Attachment

Learn, how His-Tag can be used for specific linker attachment. Another example in our LINKEROLOGY series of sophisticated linker technologies.

Lipidated Amino Acids

The tremendous success of Liraglutide and Semaglutide has moved amino acids modified with lipids into the focus of many research endeavors. Delve into the treasure trove of our lipidated amino acids!

Short arginine analogs: peptide synthesis prediction of biological effects

Arginine, a semi-essential amino acid, is involved in various important metabolic processes.

Protease Inhibitors

Protease inhibitors are molecules that inhibit protease function by binding either reversibly or irreversibly to the enzyme.

Fmoc-L-Lys(Nvoc)-OH

o -Nitroveratryloxycarbonyl (Nvoc) is a photocleavable side chain protecting group for lysine that can be removed by irradiation with UV light (350 nm).

H-L-Lys(Suc)-OH*HCl

Succinylation of proteins on the epsilon-amino group of lysine residues is a posttranslational modification that is still poorly understood.

Diazirine Amino Acids for Photo Cross-Linkage in Living Cells

Iris Biotech introduces a comprehensive set of photo-crosslinking amino acids bearing the diazirine moiety.

beta,beta-Dimethyl Amino Acids

The use of bioactive peptides has increased over the recent years as they attracted attention for their use as therapeutic agents.

Polylysines

Polylysines are polymers of the canonical amino acid Lysine, and are characterized by their high charge density caused by the presence of one free amino group per lysine monomer.

Arginine Analogues

Trypsin (EC 3.4.21.4), an endopeptidase and natural protease found in the digestive system, cleaves peptide chains and proteins predominantly at the carboxyl side of the amino acids Lys and Arg (except when followed by Pro).

Specific Linkers

The variations for linkers are endless, as in our catalogue program already hundreds of different derivatives are available for conjugation of small molecules, biomolecules and surfaces to each other.

Poly(Glutamic Acid) as Versatile Biodegradable Drug Carrier

Polyglutamates are well known to be highly biocompatible, biodegradable and multifunctional polymers, which have already been used as building blocks in polymer drug conjugates and polymeric micelles.

Polysarcosine – a True Alternative to PEG

Potential alternatives to PEGs, polypeptoids in general and polysarcosine (PSR) in particular stand out in terms of safety, synthetic control and versatility.

New: Oligo Glycine – Linker

Oligo-glycines are either flexible linkers or form well defined rigid substructures. We offer a variety of oligo-glycines as building blocks which can easily be introduced into any molecule.

New Statin Analogues: Super-Threonine Derivatives

A set of new statin analogues, so called Super-Threonines, is available consisting of Fmoc protected L-enantiomers with all possible 4 stereoisomers of chiral centers in the side chain. They appear in nature as bridge building element in cyclodepsipeptides, like pipecolidepsin A, a compound which shows relevant cytotoxic activity in three human tumor cell lines (lung, colon, breast) and has unique structural features.

Amino Aldehydes

Aldehydes are between alcohols and carboxylic acids with respect to their oxidation level and show specific reactivity. Therefore they are highly interesting building blocks and intermediates for a large number of very interesting classes of reactions and compounds such as Wittig reaction, formation of secondary alcohols, heterocycles and semiaminals to name only a few.

Linkers for Antibody-Drug Conjugation (ADC)

Cleavable dipeptide linkers like Val-Ala and Val-Cit rely on processes inside the cell to liberate the payload, as they undergo rapid hydrolysis in the presence of lysosomal extracts or purified human cathepsin B.

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.

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.

Perfluorophenyl azides as Photo Cross-Linker

Aryl azides are well-known precursors of nitrenes and have been introduced by Fleet et al . as versatile photoaffinity labeling agents to probe biological receptors.

Shorter Arginine homologues to stabilize peptides towards tryptic digestion

Abstract: Trypsin digests peptides at the position of arginine. Because shorter homologues of arginine with appropriate protecting groups for conventional Fmoc/tBu peptide synthesis are now available, three model peptides containing arginine and two shorter homologues of arginine were synthesized.

Abstract: A considerable number of biologically active naturally occurring products are peptides, depsipeptides, and peptide conjugates.

Abstract: N alpha-9-Fluorenylmethoxycarbonyl-N epsilon-4=methyltrityl-lysine, [Fmoc-Lys(Mtt)-OH], was prepared in two steps from lysine, in 42% overall yield.