19391-35-6Relevant articles and documents
Photochemical formation of quinone methides from peptides containing modified tyrosine
Husak, Antonija,Noichl, Benjamin P.,?umanovac Ramljak, Tatjana,Sohora, Margareta,?kalamera,Budi?a, Nediljko,Basari?, Nikola
, p. 10894 - 10905 (2016)
We have demonstrated that quinone methide (QM) precursors can be introduced in the peptide structure and used as photoswitchable units for peptide modifications. QM precursor 1 was prepared from protected tyrosine in the Mannich reaction, and further used as a building block in peptide synthesis. Moreover, peptides containing tyrosine can be transformed into a photoactivable QM precursor by the Mannich reaction which can afford monosubstituted derivatives 2 or bis-substituted derivatives 3. Photochemical reactivity of modified tyrosine 1 and dipeptides 2 and 3 was studied by preparative irradiation in CH3OH where photodeamination and photomethanolysis occur. QM precursors incorporated in peptides undergo photomethanolysis with quantum efficiency ΦR = 0.1-0.2, wherein the peptide backbone does not affect their photochemical reactivity. QMs formed from dipeptides were detected by laser flash photolysis (λmax ≈ 400 nm, τ = 100 μs-20 ms) and their reactivity with nucleophiles was studied. Consequently, QM precursors derived from tyrosine can be a part of the peptide backbone which can be transformed into QMs upon electronic excitation, leading to the reactions of peptides with different reagents. This proof of principle showing the ability to photochemically trigger peptide modifications and interactions with other molecules can have numerous applications in organic synthesis, materials science, biology and medicine.
Quantitative insight into the design of compounds recognized by the L-type amino acid transporter 1 (LAT1)
Ylikangas, Henna,Malmioja, Kalle,Peura, Lauri,Gynther, Mikko,Nwachukwu, Emmanuel O.,Lepp?nen, Jukka,Laine, Krista,Rautio, Jarkko,Lahtela-Kakkonen, Maija,Huttunen, Kristiina M.,Poso, Antti
supporting information, p. 2699 - 2707 (2015/02/02)
L-Type amino acid transporter 1 (LAT1) is a transmembrane protein expressed abundantly at the blood-brain barrier (BBB), where it ensures the transport of hydrophobic acids from the blood to the brain. Due to its unique substrate specificity and high expression at the BBB, LAT1 is an intriguing target for carrier- mediated transport of drugs into the brain. In this study, a comparative molecular field analysis (CoMFA) model with considerable statistical quality (Q2=0.53, R2=0.75, Q2 SE=0.77, R2 SE=0.57) and good external predictivity (CCC=0.91) was generated. The model was used to guide the synthesis of eight new prodrugs whose affinity for LAT1 was tested by using an in situ rat brain perfusion technique. This resulted in the creation of a novel LAT1 prodrug with l-tryptophan as the promoiety; it also provided a better understanding of the molecular features of LAT1-targeted high-affinity prodrugs, as well as their promoiety and parent drug. The results obtained will be beneficial in the rational design of novel LAT1-binding prodrugs and other compounds that bind to LAT1.
tert-buyldiphenylsilylethyl ("TBDPSE"): A practical protecting group for phenols
Gerstenberger, Brian S.,Konopelski, Joseph P.
, p. 1467 - 1470 (2007/10/03)
(Chemical Equation Presented) A new protection group for phenols, the 2-(tert-butyldiphenylsilyl)ethyl (TBDPSE) group, has been prepared and investigated. Protection of a variety of substituted phenols proceeds in good to excellent yield. The group is stable to mild acid, base, hydrogenolysis conditions, and lithium/ halogen exchange on the protected phenol. Removal is achieved with strong acid or standard fluoride treatment.
