16874-12-7Relevant articles and documents
Overcoming the Deallylation Problem: Palladium(II)-Catalyzed Chemo-, Regio-, and Stereoselective Allylic Oxidation of Aryl Allyl Ether, Amine, and Amino Acids
Begam, Hasina Mamataj,Jana, Ranjan,Manna, Kartic,Samanta, Krishanu
supporting information, p. 7443 - 7449 (2020/10/09)
We report herein a Pd(II)/bis-sulfoxide-catalyzed intramolecular allylic C-H acetoxylation of aryl allyl ether, amine, and amino acids with the retention of a labile allyl moiety. Mechanistically, the reaction proceeds through a distinct double-bond isomerization from the allylic to the vinylic position followed by intramolecular carboxypalladation and the β-hydride elimination pathway. For the first time, C-H oxidation of N-allyl-protected amino acids to furnish five-membered heterocycles through 1,3-syn-addition is established with excellent diastereoselectivity.
Synthesis and anticancer activities of proline-containing cyclic peptides and their linear analogs and congeners
Ghosh, Keshab Ch,Duttagupta, Indranil,Bose, Chandra,Banerjee, Priyanjalee,Gayen, Anuran Kumar,Sinha, Surajit
, p. 221 - 236 (2019/01/19)
A solution phase method was adopted for the synthesis of proline-containing cyclic pentapeptide 2 and total synthesis of naturally occurring cyclic heptapeptide Reniochalistatin B 3. For the synthesis of 3, both divergent and convergent strategies were used to improve the overall yield from 12 to 25%. Different N and C terminal modified linear analogs and congeners of 2 and 3 were synthesized. Both cyclic peptides 2 and 3 and their linear analogs/congeners were evaluated for anti-cancer activity against HeLa cell line, among which pentapeptide 2 h and hexapeptide 3n with N-terminal protected hexafluoroisopropyl carbamates (HFIPC) interestingly showed higher cytotoxicity with an IC50 of 2.73 and 4.3 μM, respectively compared to their Boc-protected analogs 2a (IC50 20 μM) and 3c (IC50 38.51 μM) and cyclic peptides 2 (>100 μM) and 3 (47 μM). These results were further validated by biological experiments such as colony formation and wound healing assays.
Base/Cryptand/Metal-Free Automated Nucleophilic Radiofluorination of [18F]FDOPA from Iodonium Salts: Importance of Hydrogen Carbonate Counterion
Maisonial-Besset, Aurélie,Serre, Audrey,Ouadi, Ali,Schmitt, Sébastien,Canitrot, Damien,Léal, Fernand,Miot-Noirault, Elisabeth,Brasse, David,Marchand, Patrice,Chezal, Jean-Michel
supporting information, p. 7058 - 7065 (2019/01/04)
As evidenced by the number of publications and patents published in the last years, the radiosynthesis of 6-[18F]fluoro-3,4-dihydroxy-L-phenylalanine ([18F]FDOPA) using the nucleophilic [18F]F- process remains currently a challenge for the radiochemists scientific community even if promising methods for the radiofluorination of electron-rich aromatic structures were recently developed from arylboronate, arylstannane or iodonium salt precursors. In such context, based on the use of an iodonium triflate salt precursor, we optimized a fast and efficient radiofluorination route fully automated and free from any base, cryptand or metal catalyst for the radiosynthesis of [18F]FDOPA. Using this method, this clinically relevant radiotracer was produced in 64 min, 27–38 % RCY d.c. (n = 5), >99 % RCP, >99 % ee., and high Am 170–230 GBq/μmol. In addition, this optimization study clearly highlighted the important role of a triflate-hydrogen carbonate counterion exchange during the radiolabeling process to achieve high fluorine-18 incorporation yields.
A Bioinspired Synthesis of Polyfunctional Indoles
Huang, Zheng,Kwon, Ohhyeon,Huang, Haiyan,Fadli, Aziz,Marat, Xavier,Moreau, Magali,Lumb, Jean-Philip
supporting information, p. 11963 - 11967 (2018/09/11)
Polyfunctional indoles bearing substituents at C5 and C6 are prevalent in natural products, pharmaceuticals, agrochemicals, and materials. Owing to the remoteness of the C5 and C6 positions, indoles of this family can be difficult to prepare, and often require multistep syntheses. Herein, we describe a concise process that converts simple derivatives of tyrosine into 5,6-difunctionalized indoles by direct oxidation of C?H, N?H, and O?H bonds. Our work draws inspiration from the biosynthetic polymerization of tyrosine to make melanin pigments, but makes an important departure to provide well-defined indole heterocycles.
A novel SWCNT platform bearing DOTA and β-cyclodextrin units. "one shot" multidecoration under microwave irradiation
Calcio Gaudino,Tagliapietra,Martina,Barge,Lolli,Terreno,Lembo,Cravotto
supporting information, p. 4708 - 4715 (2014/06/24)
The functionalization of single-walled carbon nanotubes (SWCNTs) via microwave-assisted grafting reactions enables efficient multidecoration in a single step. A novel water-soluble SWCNT platform was prepared via the simple 1,3-dipolar cycloaddition of azomethine ylides under dielectric heating. Thanks to a single grafting reaction the CNT surface binds in a 1:1 ratio an amino acidic β-cyclodextrin (β-CD) derivative and the DOTAMA moiety (1,4,7,10-tetraazacyclododecane-N,N′,N′′,N′′ ′-tetraacetic acid monoamide). This novel "one shot" synthesis, compared with multistep functionalizations, preserves the SWCNT's structural integrity (TEM images). Besides thermogravimetric analyses, the determination of the amount of β-CD and DOTA moieties grafting onto the SWCNT's surface was performed on the basis of phenolphthalein and gadolinium complexation, respectively. This journal is
MODULATORS OF TLR3/DSRNA COMPLEX AND USES THEREOF
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Page/Page column 24, (2012/08/07)
The present invention provides compounds and compositions that can modulate formation of Toll-like receptor 3 (TLR3) and double-stranded RNA (dsRNA) complex, and methods for using the same. In particular, some aspects of the invention provide compounds of the formula (I) compositions comprising and methods for using the same, where n, Ar1, Ar2, X1, X2, X3, Z1, and Z2 are those defined herein.
Small-molecule inhibitors of the TLR3/dsRNA complex
Cheng, Kui,Wang, Xiaohui,Yin, Hang
supporting information; experimental part, p. 3764 - 3767 (2011/06/18)
The protein-RNA interface has been regarded as "undruggable" despite its importance in many biological processes. The toll-like receptor 3 (TLR3)/double-stranded RNA (dsRNA) complex provides an exciting target for a number of infectious diseases and cancers. We describe the development of a series of small-molecule probes that were shown to be competitive inhibitors of dsRNA binding to TLR3 with high affinity and specificity. In a multitude of assays, compound 4a was profiled as a potent antagonist to TLR3 signaling and also repressed the expression of downstream signaling pathways mediated by the TLR3/dsRNA complex, including TNF-α and IL-1β.
COMPOSITIONS AND METHODS FOR CYCLOFRUCTANS AS SEPARATION AGENTS
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Page/Page column 45-49; 59, (2010/12/31)
The present invention relates to derivatized cyclofructan compounds, compositions comprising derivatized cyclofructan compounds, and methods of using compositions comprising derivatized cyclofructan compounds for chromatographic separations of chemical species, including enantiomers. Said compositions may comprise a solid support and/or polymers comprising derivatized cyclofructan compounds.
αvβ3 integrin-targeting Arg-Gly-Asp (RGD) peptidomimetics containing oligoethylene glycol (OEG) spacers
Rerat, Vincent,Dive, Georges,Cordi, Alex A.,Tucker, Gordon C.,Bareille, Reine,Amédée, Jo?lle,Bordenave, Laurence,Marchand-Brynaert, Jacqueline
supporting information; experimental part, p. 7029 - 7043 (2010/07/05)
RGD peptides are used in biomaterials science for surface modifications with a view to elicit selective cellular responses. Our objective is to replace peptides by small peptidomimetics acting similarly. We designed novel molecules targeting αvβ3 integrin and featuring spacer-arms (for surface grafting), which do not disturb the biological activity, from (L) N-(3-(trifluoromethyl)benzenesulfonyl) tyrosine used as scaffold. Various Arg-mimics were fixed on the phenol function, and the ortho position was used for the coupling of OEG spacers. All peptidomimetics were active in the nM range in a binding test toward human αvβ 3 integrin (IC50 = 0.1 to 1.7 nM) and selective versus platelet integrin αIIbβ3. Selected compounds revealed excellent ability to inhibit bone cells adhesion on vitronectin. Modeling and docking studies were performed for comparing the most active RGD peptidomimetic to cilengitide, i.e., cyclo-[RGDfN(Me)V]-. Lastly, the adhesion of endothelial cells on a cultivation support grafted with RGD peptidomimetics was significantly improved. 2009 American Chemical Society.
Design of new, chiral phase-transfer catalysts for practical, catalytic asymmetric synthesis
Maruoka, Keiji
, p. 95 - 99 (2007/10/03)
Structurally rigid, chiral spiro ammonium salts of type 1 derived from commercially available (S)-binaphthol have been designed as a new C2-symmetric chiral phase-transfer catalyst and successfully applied to the highly efficient, catalytic enantioselective alkylation of tert-butyl glycinate Schiff base under mild phase-transfer conditions to furnish a-alkyl-oc-amino acids and α,α-dialkyl-α-amino acids with excellent enantioselectivity. These ammonium salts have been also utilized for the in situ generation of chiral quaternary ammonium fluorides.