65160-70-5

Upstream product

• 67-56-1 methanol 
• 74-79-3 L-arginine 
• 1119-34-2 L-arginine hydrochloride 

Downstream Products

• 102683-28-3 N-(benzyloxycarbonyl)-L-tyrosyl-D-arginine methyl ester 
• 18598-72-6 N^α-trityl-L-arginine methyl ester 
• 116097-82-6 Z-Asp(OCH₃)-Arg-OCH₃ 
• 77935-56-9 H-Tyr(Bzl)-Arg-OMe*2HCl 
• 102683-29-4 N-(benzyloxycarbonyl)-L-tyrosyl-L-arginine methyl ester 
• 81189-59-5 Boc-D-Tyr(Br-Z)-Arg-OMe 
• 122774-39-4 For-Tyr-Arg-OMe 
• 34522-32-2 N₂-(D-1-carboxyethyl)-L-arginine 
• 6072-05-5 Z-Arg-OMe 
• 301181-35-1 Boc-Lys(Cbz)-Arg-OMe 

Relevant academic research and scientific papers

Modified histidine containing amphipathic ultrashort antifungal peptide, His[2-p-(n-butyl)phenyl]-Trp-Arg-OMe exhibits potent anticryptococcal activity

In pursuit of ultrashort peptide-based antifungals, a new structural class, His(2-aryl)-Trp-Arg is reported. Structural changes were investigated on His-Trp-Arg scaffold to demonstrate the impact of charge and lipophilic character on the biological activity. The presence and size of the aryl moiety on imidazole of histidine modulated overall amphiphilic character, and biological activity. Peptides exhibited IC50 of 0.37–9.66 μg/mL against C. neoformans. Peptide 14f [His(2-p-(n-butyl)phenyl)-Trp-Arg-OMe] exhibited two-fold potency (IC50 = 0.37 μg/mL, MIC = 0.63 μg/mL) related to amphotericin B, without any cytotoxic effects up to 10 μg/mL. Peptide 14f act by nuclear fragmentation, membranes permeabilization, disruption and pore formations in the microbial cells as determined by the mechanistic studies employing Trp-quenching, CLSM, SEM, and HR-TEM. The amalgamation of short sequence, presence of appropriate aryl group on L-histidine, potent anticryptococcal activity, no cytotoxicity, and detailed mechanistic studies directed to the identification of 14f as a new antifungal structural lead.

Unveiling and tackling guanidinium peptide coupling reagent side reactions towards the development of peptide-drug conjugates

Peptide coupling reagents and especially uronium/guanidinium salts have been extensively utilized in solid-phase peptide synthesis. However, the impact of these reagents in solution phase synthesis, normally used in the formation of peptide-drug conjugates (PDCs), has not been fully explored. Herein, we identified that when guanidinium salts are used in classical peptide coupling conditions, besides leading to the formation of amide bonds, a uronium derivative can also be installed on specific amino acid scaffolds. The formation of this side product depends on the reaction conditions, as also on the nucleophilicity of the susceptible groups. Conditions to avoid this side product formation and a putative reaction mechanism describing its formation are reported.