21933-50-6

Upstream product

• 47365-05-9 (S)-5-[1-(benzyloxycarbonylamino)-2-phenyl-ethyl]-2H-tetrazole 
• 47365-05-9 benzyl (S)-(2-phenyl-1-(1H-tetrazol-5-yl)ethyl)carbamate 
• 21947-21-7 (S)-N-benzyloxycarbonyl-2-amino-3-phenyl-propionitrile 
• 5241-56-5 benzyl [(2S)-1-amino-1-oxo-3-phenylpropan-2-yl]carbamate 
• 1161-13-3 N-Cbz-L-Phe 
• 63-91-2 L-phenylalanine 

Downstream Products

• 920017-34-1 Boc-Dap-Phe-tetrazole 
• 145385-59-7 (S)-3-(8-Amino-octanoylamino)-N-[(S)-2-phenyl-1-(1H-tetrazol-5-yl)-ethyl]-succinamic acid 

Relevant academic research and scientific papers

A new chiral synthesis of a bicyclic enedione containing a seven-membered ring mediated by a combination of chiral amine and Bronsted acid

Several chiral amines bearing a heterocyclic moiety such as pyrrolidine, piperazine or tetrazole were prepared from l-phenylalanine. The enantioselectivity of the intramolecular asymmetric aldol reaction mediated by a combination of the synthetic chiral a

LAT1 activity of carboxylic acid bioisosteres: Evaluation of hydroxamic acids as substrates

Large neutral amino acid transporter 1 (LAT1) is a solute carrier protein located primarily in the blood–brain barrier (BBB) that offers the potential to deliver drugs to the brain. It is also up-regulated in cancer cells, as part of a tumor's increased metabolic demands. Previously, amino acid prodrugs have been shown to be transported by LAT1. Carboxylic acid bioisosteres may afford prodrugs with an altered physicochemical and pharmacokinetic profile than those derived from natural amino acids, allowing for higher brain or tumor levels of drug and/or lower toxicity. The effect of replacing phenylalanine's carboxylic acid with a tetrazole, acylsulfonamide and hydroxamic acid (HA) bioisostere was examined. Compounds were tested for their ability to be LAT1 substrates using both cis-inhibition and trans-stimulation cell assays. As HA-Phe demonstrated weak substrate activity, its structure–activity relationship (SAR) was further explored by synthesis and testing of HA derivatives of other LAT1 amino acid substrates (i.e., Tyr, Leu, Ile, and Met). The potential for a false positive in the trans-stimulation assay caused by parent amino acid was evaluated by conducting compound stability experiments for both HA-Leu and the corresponding methyl ester derivative. We concluded that HA's are transported by LAT1. In addition, our results lend support to a recent account that amino acid esters are LAT1 substrates, and that hydrogen bonding may be as important as charge for interaction with the transporter binding site.

Glycosylation mediated - BAIL in aqueous solution

The use of Br?nsted acid ionic liquid (BAIL) as a catalyst for the activation of unreactive and unprotected glycosyl donors has been demonstrated for the first time in aqueous solution.

Synthesis of tetrazole analogues of amino acids using Fmoc chemistry: isolation of amino free tetrazoles and their incorporation into peptides

An efficient synthesis of tetrazole analogues of amino acids starting from Nα-Fmoc amino acid in a three-step protocol is reported. The free amino tetrazoles were obtained in good yields and with excellent purity after removal of the Fmoc group

MONOMETHYLVALINE COMPOUNDS HAVING PHENYLALANINE CARBOXY MODIFICATIONS AT THE C-TERMINUS

Auristatin peptide analogs of MeVal-Val-Dil-Dap-Phe (MMAF) having a carboxylic acid equivalent at the C-terminal phenylalanine were prepared and attached to ligands through various linkers, including maleimidocaproyl-val-cit-PAB. The resulting ligand drug conjugates were active in vitro and in vivo.