3674-06-4Relevant articles and documents
Synthesis of pyrimidine nucleoside and amino acid conjugates
Koplūnait?, Martyna,Butkut?, Kamil?,Me?kys, Rolandas,Taurait?, Daiva
supporting information, (2020/11/13)
The synthesis of novel pyrimidine nucleoside bioconjugates with amino acids is presented. The N4-amino acid-acylated 2′-deoxycytidine analogues, modified with various amino acids, were synthesized using a three-step synthesis and obtained in moderate overall yields. Novel amino acid-alkylated 2′-deoxycytidine derivatives were obtained during the rearrangement of amino acid-acylated derivatives that occurred during Boc deprotection.
Synthesis, Characterization and in vitro Studies of a Cathepsin B-Cleavable Prodrug of the VEGFR Inhibitor Sunitinib
Karnthaler-Benbakka, Claudia,Koblmüller, Bettina,Mathuber, Marlene,Holste, Katharina,Berger, Walter,Heffeter, Petra,Kowol, Christian R.,Keppler, Bernhard K.
, (2019/01/04)
Since several decades, the prodrug concept has raised considerable interest in cancer research due to its potential to overcome common problems associated with chemotherapy. However, for small-molecule tyrosine kinase inhibitors, which also cause severe side effects, hardly any strategies to generate prodrugs for therapeutic improvement have been reported so far. Here, we present the synthesis and biological investigation of a cathepsin B-cleavable prodrug of the VEGFR inhibitor sunitinib. Cell viability assays and Western blot analyses revealed, that, in contrast to the non-cathepsin B-cleavable reference compound, the prodrug shows activity comparable to the original drug sunitinib in the highly cathepsin B-expressing cell lines Caki-1 and RU-MH. Moreover, a cathepsin B cleavage assay confirmed the desired enzymatic activation of the prodrug. Together, the obtained data show that the concept of cathepsin B-cleavable prodrugs can be transferred to the class of targeted therapeutics, allowing the development of optimized tyrosine kinase inhibitors for the treatment of cancer.
The Cooperative Effect of Both Molecular and Supramolecular Chirality on Cell Adhesion
Liu, Jinying,Yuan, Feng,Ma, Xiaoyu,Auphedeous, Dang-i Y.,Zhao, Changli,Liu, Chuntai,Shen, Changyu,Feng, Chuanliang
supporting information, p. 6475 - 6479 (2018/05/08)
Although helical nanofibrous structures have great influence on cell adhesion, the role played by chiral molecules in these structures on cells behavior has usually been ignored. The chirality of helical nanofibers is inverted by the odd–even effect of methylene units from homochiral l-phenylalanine derivative during assembly. An increase in cell adhesion on left-handed nanofibers and weak influence of cell behaviors on right-handed nanofibers are observed, even though both were derived from l-phenylalanine derivatives. Weak and negative influences on cell behavior was also observed for left- and right-handed nanofibers derived from d-phenylalanine, respectively. The effect on cell adhesion of single chiral molecules and helical nanofibers may be mutually offset.
Binding and Action of Amino Acid Analogs of Chloramphenicol upon the Bacterial Ribosome
Tereshchenkov, Andrey G.,Dobosz-Bartoszek, Malgorzata,Osterman, Ilya A.,Marks, James,Sergeeva, Vasilina A.,Kasatsky, Pavel,Komarova, Ekaterina S.,Stavrianidi, Andrey N.,Rodin, Igor A.,Konevega, Andrey L.,Sergiev, Petr V.,Sumbatyan, Natalia V.,Mankin, Alexander S.,Bogdanov, Alexey A.,Polikanov, Yury S.
, p. 842 - 852 (2018/02/26)
Antibiotic chloramphenicol (CHL) binds with a moderate affinity at the peptidyl transferase center of the bacterial ribosome and inhibits peptide bond formation. As an approach for modifying and potentially improving properties of this inhibitor, we explored ribosome binding and inhibitory activity of a number of amino acid analogs of CHL. The L-histidyl analog binds to the ribosome with the affinity exceeding that of CHL by 10 fold. Several of the newly synthesized analogs were able to inhibit protein synthesis and exhibited the mode of action that was distinct from the action of CHL. However, the inhibitory properties of the semi-synthetic CHL analogs did not correlate with their affinity and in general, the amino acid analogs of CHL were less active inhibitors of translation in comparison with the original antibiotic. The X-ray crystal structures of the Thermus thermophilus 70S ribosome in complex with three semi-synthetic analogs showed that CHL derivatives bind at the peptidyl transferase center, where the aminoacyl moiety of the tested compounds established idiosyncratic interactions with rRNA. Although still fairly inefficient inhibitors of translation, the synthesized compounds represent promising chemical scaffolds that target the peptidyl transferase center of the ribosome and potentially are suitable for further exploration.
New Class of Selective Estrogen Receptor Degraders (SERDs): Expanding the Toolbox of PROTAC Degrons
Wang, Lucia,Guillen, Valeria S.,Sharma, Naina,Flessa, Kevin,Min, Jian,Carlson, Kathryn E.,Toy, Weiyi,Braqi, Sara,Katzenellenbogen, Benita S.,Katzenellenbogen, John A.,Chandarlapaty, Sarat,Sharma, Abhishek
supporting information, p. 803 - 808 (2018/07/21)
An effective endocrine therapy for breast cancer is to selectively and effectively degrade the estrogen receptor (ER). Up until now, there have been largely only two molecular scaffolds capable of doing this. In this study, we have developed new classes of scaffolds that possess selective estrogen receptor degrader (SERD) and ER antagonistic properties. These novel SERDs potently inhibit MCF-7 breast cancer cell proliferation and the expression of ER target genes, and their efficacy is comparable to Fulvestrant. Unlike Fulvestrant, the modular protein-targeted chimera (PROTAC)-type design of these novel SERDs should allow easy diversification into a library of analogs to further fine-tune their pharmacokinetic properties including oral availability. This work also expands the pool of currently available PROTAC-type scaffolds that could be beneficial for targeted degradation of various other therapeutically important proteins.
Photocyclization of Tetra- and Pentapeptides Containing Adamantylphthalimide and Phenylalanines: Reaction Efficiency and Diastereoselectivity
Sohora, Margareta,Vazdar, Mario,Sovi?, Irena,Mlinari?-Majerski, Kata,Basari?, Nikola
, p. 14905 - 14922 (2019/01/04)
A series of tetrapeptides and pentapeptides was synthesized bearing a phthalimide chromophore at the N-terminus. The C-terminus of the peptides was strategically substituted with an amino acid, Phe, Phe(OMe), or Phe(OMe)2 characterized by different oxidation potentials. The photochemical reactivity of the peptides was investigated by preparative irradiation and isolation of photoproducts, as well as with laser flash photolysis. Upon photoexcitation, the peptides undergo photoinduced electron transfer (PET) and decarboxylation, followed by diastereoselective cyclization with the retention of configuration for tetrapeptides or inversion of configuration for pentapeptides. Molecular dynamics (MD) simulations and NOE experiments enabled assignment of the stereochemistry of the cyclic peptides. MD simulations of the linear peptides disclosed conformational reasons for the observed diastereoselectivity, being due to the peptide backbone spatial orientation imposed by the Phe amino acids. The photochemical efficiency for the decarboxylation and cyclization is not dependent on the peptide length, but it depends on the oxidation potential of the amino acid at the C-terminus. The results described herein are particularly important for the rational design of efficient photochemical reactions for the preparation of cyclic peptides with the desired selectivity.
Synthesis and photochemical reactivity of phthalimidoadamantane–tyrosine conjugates
Sohora, Margareta,Vidovi?, Nikolina,Mlinari?-Majerski, Kata,Basari?, Nikola
, p. 5305 - 5320 (2017/09/23)
Abstract: Dipeptide 3, tetrapeptide 4 and pentapeptide 5, containing adamantylphthalimide and tyrosine, were synthesized and their photochemical reactivity investigated. Upon excitation to the triplet excited state, 3 does not give any photoproduct, although the photoinduced electron transfer (PET) should take place based on the thermodynamic properties. Tetrapeptide 4 and pentapeptide 5 are photochemically reactive, undergoing decomposition upon excitation. The lack of anticipated photodecarboxylation reactivity is explained by PET between the tyrosine and the phthalimide. However, deprotonation of the phenoxyl radical-cation giving phenoxyl radicals or back electron transfer giving starting material are probably faster than intrastrand single electron transfer which would lead to carboxyl radical and decarboxylation. The results indicate the importance of fine-tuning the molecular structure to attain the desired photoreactivity by the right choice of the reactants redox potential, as well as their acid/base properties.
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
supporting information, p. 10894 - 10905 (2016/12/06)
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.
N,O-Bis(trimethylsilyl)acetamide/N-hydroxysuccinimide ester (BSA/NHS) as coupling agents for dipeptide synthesis
Huang, Ye,Feng, Wen-Hua
, p. 357 - 360 (2016/03/16)
A method using N,O-bis(trimethylsilyl)acetamide/N-hydroxysuccinimide ester (BSA/NHS) as coupling agents for dipeptide synthesis is descried. The coupling reaction between N-hydroxysuccinimide (NHS) esters and amines could be performed under mild conditions with N,O-bis(trimethylsilyl)acetamide (BSA) as coupling reagent and no additional acid/base is required. All byproducts and excessive reactants are water soluble or hydrolysable and easy to eliminate through water-washing at the purification stage. Moreover, all the reactants are inexpensive and widely used in conventional drug production.
Mechanistic insight into the lability of the benzyloxycarbonyl (Z) group in N-protected peptides under mild basic conditions
Tena-Solsona, Marta,Angulo-Pachon, Cesar A.,Escuder, Beatriu,Miravet, Juan F.
supporting information, p. 3372 - 3378 (2014/06/09)
An unexpected lability of the benzyloxycarbonyl (Z) protecting group under mild basic conditions at room temperature is explained by a mechanism based on anchimeric assistance. It is found that the vicinal amide group stabilises the tetrahedral intermediate formed after nucleophilic addition of hydroxide to the carbonyl of the Z group. This effect operates in N-protected tripeptides and tetrapeptides but Z-protected dipeptides are stable under the same conditions due to blockage of the vicinal amide NH by intramolecular H-bonding with the terminal carboxylate moiety. Copyright
