189455-66-1

Upstream product

• 35661-39-3 N-[(9H-fluoren-9-ylmethoxy)carbonyl]-L-alanine 
• 35661-40-6 N-Fmoc L-Phe 
• 56-41-7 L-alanin 
• 84890-98-2 Fmoc-Phe-O-COO-isoBu 
• 5269-38-5 L-alanine trimethylsilyl ester 
• 103321-57-9 2S-flouren-9-ylmethoxycarbonylamino-3-phenylpropionyl chloride 
• 118474-95-6 (S)-methyl 2-((S)-2-((((9H-fluoren-9-yl)methoxy)carbonyl)amino)-3-phenylpropanamido)propanoate 
• 860800-19-7 9H-fluoren-9-ylmethyl N-[(1S)-1-benzyl-2-benzotriazol-1-yl-2-oxoethyl]carbamate 
• 13404-22-3 tert-butyl L-alaninate hydrochloride 
• 233281-34-0 N-(9-fluorenylmethyloxycarbonyl)phenylalanylalanine 3,4,5-tris(octadecyloxy)benzyl ester 

Downstream Products

• 1349173-20-1 Fmoc-Phe-D-Ala-OSu 
• 1349173-19-8 Fmoc-Phe-Ala-OSu 
• 1197342-94-1 Fmoc-L-Phe-L-Ala-SH 
• 1027955-03-8 [1-(1-azidocarbonyl-ethylcarbamoyl)-2-phenyl-ethyl]-carbamic acid 9H-fluoren-9-ylmethyl ester 
• 918625-51-1 [1-(1-isocyanato-ethylcarbamoyl)-2-phenyl-ethyl]-carbamic acid 9H-fluoren-9-ylmethyl ester 

Relevant academic research and scientific papers

Characterization of Nα-Fmoc-protected dipeptide isomers by electrospray ionization tandem mass spectrometry (ESI-MSn): Effect of protecting group on fragmentation of dipeptides

A series of positional isomeric pairs of Fmoc-protected dipeptides, Fmoc-Gly-Xxx-OY/Fmoc-Xxx-Gly-OY (Xxx = Ala, Val, Leu, Phe) and Fmoc-Ala-Xxx-OY/Fmoc-Xxx-Ala-OY (Xxx = Leu, Phe) (Fmoc = [(9-fluorenylmethyl) oxy]carbonyl) and Y = CH3/H), have been characterized and differentiated by both positive and negative ion electrospray ionization ion-trap tandem mass spectrometry (ESI-IT-MSn). In contrast to the behavior of reported unprotected dipeptide isomers which mainly produce y 1+ and/or a1+ ions, the protonated Fmoc-Xxx-Gly-OY, Fmoc-Ala-Xxx-OY and Fmoc-Xxx-Ala-OY yield significant b 1+ ions. These ions are formed, presumably with stable protonated aziridinone structures. However, the peptides with Gly- at the N-terminus do not form b1+ ions. The [M + H]+ ions of all the peptides undergo a McLafferty-type rearrangement followed by loss of CO2 to form [M + H-Fmoc + H]+. The MS3 collision-induced dissociation (CID) of these ions helps distinguish the pairs of isomeric dipeptides studied in this work. Further, negative ion MS 3 CID has also been found to be useful for differentiating these isomeric peptide acids. The MS3 of [M-H-Fmoc + H]- of isomeric peptide acids produce c1-, z1 - and y1- ions. Thus the present study of Fmoc-protected peptides provides additional information on mass spectral characterization of the dipeptides and distinguishes the positional isomers. Copyright

Benzoisothiazolone (BIT): A Fast, Efficient, and Recyclable Redox Reagent for Solid Phase Peptide Synthesis

Solid-phase peptide synthesis (SPPS), a preferred synthetic procedure, generates by-products and effluents in multiple equivalents for one equivalent of desired product. Presented herein is the use of a fast and efficient coupling protocol for SPPS using a benzoisothiazolone (BIT), which can be fully recycled. The BIT, as redox activator, works under very mild conditions and generates minimal amount of waste. As a case study, the BIT coupling protocol is applied to the synthesis of side chain of the recently discovered antibiotic, teixobactin.

A simple method for the generation of chloromethyl polystyrene on the Multipin(TM) solid support

A novel route for the chloromethylation of polystyrene grafted Multipin supports (Synphase(TM) Crowns) has been developed. Aminomethylated polystyrene was converted into chloromethylated polystyrene via a simple diazotisation reaction. The modified graft polymer was assessed by solid phase synthesis of a model dipeptide.

Extended Solution-phase Peptide Synthesis Strategy Using Isostearyl-Mixed Anhydride Coupling and a New C-Terminal Silyl Ester-Protecting Group forN-Methylated Cyclic Peptide Production

Herein, we present a new and efficient convergent solution-phase synthetic strategy for producing peptides containingN-methyl amino acids. Specifically, we have synthesized a model cyclic octapeptide with twoN-methyl amino acids, utilizing an isostearyl-m

Isostearyl Mixed Anhydrides for the Preparation of N-Methylated Peptides Using C-Terminally Unprotected N-Methylamino Acids

Sustainable and efficient manufacturing methods for N-methylated peptides remain underexplored despite growing interest in therapeutic N-methylated peptides within the pharmaceutical industry. A methodology for the coupling of C-terminally unprotected N-methylamino acids mediated by an isostearic acid halide (ISTAX) and silylating reagent has been developed. This approach allows for the coupling of a wide variety of amino acids and peptides in high yields under mild conditions without the need for a C-terminal deprotection step in the process of C-terminal elongation. These advantages make this a useful synthetic method for the production of peptide therapeutics and diagnostics containing N-methylamino acids.

α-N-Protected dipeptide acids: A simple and efficient synthesis via the easily accessible mixed anhydride method using free amino acids in DMSO and tetrabutylammonium hydroxide

The importance of dipeptides both in medicinal and pharmacological fields is well documented and many efforts have been made to find simple and efficient methods for their synthesis. For this reason, we have investigated the synthesis of α-N-protected dipeptide acids by reacting the easily accessible mixed anhydride of α-N-protected amino acids with free amino acids under different reaction conditions. The combination of TBA-OH and DMSO has been found to be the best to overcome the low solubility of amino acids in organic solvents. Under these experimental conditions, the homogeneous phase condensation reaction occurs rapidly and without detectable epimerization. The present method is also applicable to side-chain unprotected Tyr, Trp, Glu, and Asp but not Lys. This latter residue is able to engage two molecules of mixed anhydride giving the corresponding isotripeptide. Moreover, the applicability of this protocol for the synthesis of tri- and tetrapeptides has been tested. This approach reduces the need for protecting groups, is cost effective, scalable, and yields dipeptide acids that can be used as building blocks in the synthesis of larger peptides.

Heating and microwave assisted SPPS of C-terminal acid peptides on trityl resin: The truth behind the yield

Despite correct purity of crude peptides prepared on trityl resin by Fmoc/tBu microwave assisted solid phase peptide synthesis, surprisingly, lower yields than those expected were obtained while preparing C-terminal acid peptides. This could be explained

Aziridine-mediated ligation and site-specific modification of unprotected peptides

A synthesis of aziridine-containing peptides via the Cu(II)-promoted coupling of unprotected peptide thioacids and N-H aziridine-2-carbonyl peptides is reported. The unique reactivity of the resulting N-acylated aziridine-2-carbonyl peptides facilitates t

An efficient method for the preparation of peptide alcohols

N-Protected ll-dipeptide alcohols 3a-p, diastereomeric mixture (3d + 3d′) and tripeptide alcohols 6a-c were synthesized by treatment of various amino alcohols with N-protected(α-aminoacyl)benzotriazoles 1a-c, 1f-m, (1a + 1a′) and N-protected(α-dipeptidoyl)benzotriazoles 5a, 5b respectively in good yields with complete retention of chirality.

Carbocations in action. Design, synthesis, and evaluation of a highly acid-sensitive naphthalene-based backbone amide linker for solid-phase synthesis

(Diagram presented) The design, synthesis, and properties of an extremely acid-labile backbone amide linker based on a regiospecifically substituted tetraalkoxy naphthaldehyde core are presented. This handle enables cleavage of peptide backbone amides (se