32404-28-7Relevant articles and documents
The Regioselective Synthesis of o -Nitrobenzyl DOPA Derivatives
Schneider, Tobias,Martin, Joshua,Durkin, Patrick M.,Kubyshkin, Vladimir,Budisa, Nediljko
, p. 2691 - 2699 (2017/06/13)
Photocaged DOPA derivatives may serve for non-invasive unmasking of the catechol fragment in biological systems. This would enable efficient control of the redox and metal-coordinating properties associated with the free catechol moiety, in particular, in biosynthetically produced adhesive proteins and synthetic peptides. Synthetic routes towards photocaged DOPA derivatives are reported herein. A new method for preparing para -alkylated DOPA starting from 3,4-dihydroxybenzaldehyde is described for the first time.
Dual-fluorescence l -amino acid reports insertion and orientation of melittin peptide in cell membranes
Postupalenko, Viktoriia Y.,Zamotaiev, Oleksandr M.,Shvadchak, Volodymyr V.,Strizhak, Aleksandr V.,Pivovarenko, Vasyl G.,Klymchenko, Andrey S.,Mely, Yves
, p. 1998 - 2007 (2014/01/06)
Monitoring insertion and orientation of peptides in situ on cell membranes remains a challenge. To this end, we synthesized an l-amino acid (AFaa) containing a dual-fluorescence dye of the 3-hydroxyflavone family, as a side chain. In contrast to other labeling approaches using a flexible linker, the AFaa fluorophore, introduced by solid phase synthesis into desired position of a peptide, is attached closely to its backbone with well-defined orientation, and, therefore, could reflect its localization in the membrane. This concept was validated by replacing the leucine-9 (L9) and tryptophan-19 (W19) residues by AFaa in melittin, a well-studied membrane-active peptide. Due to high sensitivity of AFaa dual emission to the environment polarity, we detected a much deeper insertion of L9 peptide position into the bilayer, compared to the W19 position. Moreover, using fluorescence microscopy with a polarized light excitation, we found different orientation of AFaa at L9 and W19 positions of melittin in the bilayers of giant vesicles and cellular membranes. These results suggested that in the natural membranes, similarly to the model lipid bilayers, melittin is preferentially oriented parallel to the membrane surface. The developed amino acid and the proposed methodology will be of interest to study other membrane peptides.
Discovery of a novel nonphosphorylated pentapeptide motif displaying high affinity for Grb2-SH2 domain by the utilization of 3′-substituted tyrosine derivatives
Song, Yan-Li,Peach, Megan L.,Roller, Peter P.,Qiu, Su,Wang, Shaomeng,Long, Ya-Qiu
, p. 1585 - 1596 (2007/10/03)
The growth factor receptor-bound protein 2 (Grb2) is an SH2 domain-containing docking module that represents an attractive target for anticancer therapeutic intervention. An impressive number of synthetic Grb2-SH2 domain inhibitors have been identified; however, clinical agents operating by this mechanism are lacking, due in part to the unique requirement of anionic phosphate-mimicking functionality for high SH2 domain-binding affinity or the extended peptide nature of most inhibitors. In the current study, a new binding motif was successfully developed by the incorporation of 3′-substituted tyrosine derivatives into a simplified nonphosphorylated cyclic pentapeptide scaffold (4), which resulted in high affinity Grb2-SH2 inhibitors without any phosphotyrosine or phosphotyrosine mimetics. The new L-amino acid analogues bearing an additional nitro, amino, hydroxy, methoxy or carboxy group at the 3′-position of the phenol ring of tyrosine were prepared in an orthogonally protected form suitable for solid-phase peptide synthesis using Fmoc protocols. The incorporation of these residues into cyclic peptides composed of a five-amino acid sequence motif, Xx′-Leu-(3′- substituted-Tyr)-Ac6c-Asn, provided a brand new class of nonphosphorylated Grb2 SH2 domain inhibitors with reduced size, charge and peptidic character. The highest binding affinity was exhibited by the 3′-aminotyrosine (3′-NH2-Tyr)-containing (R)-sulfoxide-cyclized pentapeptide (10b) with an IC50 = 58 nM, the first example with low-nanomolar affinity for a five-amino acid long sequence binding to Grb2-SH2 domain free of any phosphotyrosine or phosphotyrosine mimics. However, the incorporation of 3′-NO2-Tyr, 3′-OH-Tyr or 3′-OCH3-Tyr surrogates in the pentapeptide scaffold is detrimental to Grb2-SH2 binding. These observations were rationalized using molecular modeling. More significantly, the best Grb2-SH2 inhibitor 10b showed excellent activity in inhibiting the growth of erbB2-dependent MDA-MB-453 tumor cell lines with an IC50 value of 19 nM. This study is the first attempt to identify novel nonphosphorylated high affinity Grb2 SH2 inhibitors by the utilization of 3′-substituted tyrosine derivatives, providing a promising new strategy and template for the development of non-pTyr-containing Grb2-SH2 domain antagonists with potent cellular activity, which potentially may find value in chemical therapeutics for erbB2-related cancers.
