51528-22-4Relevant academic research and scientific papers
Healable network polymers bearing flexible poly(lauryl methacrylate) chains via thermo-reversible furan-maleimide diels–alder reaction
Patil, Sachin S.,Torris, Arun,Wadgaonkar, Prakash P.
, p. 2700 - 2712 (2017)
A new ATRP initiator containing two furyl rings, namely, bis(furan-2-ylmethyl) 2-bromopentanedioate was synthesized starting from commercially available l-glutamic acid as a precursor. Well-defined bisfuryl-terminated poly(lauryl methacrylate) macromonomers with molecular weight and dispersity in the range 5000–12,000 g mol?1 and 1.30–1.37, respectively, were synthesized employing the initiator by atom transfer radical polymerization (ATRP). Independently, 1,1′,1″-(nitrilotris(ethane-2,1-diyl))tris(1H-pyrrole-2,5-dione) was synthesized as a tris-maleimide counterpart for furan-maleimide click reaction. Thermo-reversible network polymer bearing flexible poly(lauryl methacrylate; (PLMA) chains was obtained by furan-maleimide Diels–Alder click reaction of bisfuryl-terminated PLMA with 1,1′,1″-(nitrilotris(ethane-2,1-diyl))tris(1H-pyrrole-2,5-dione). The prepared network polymer showed retro-Diels–Alder reaction in the temperature range 110–170 °C as determined from DSC analysis. The presence of low Tg (–40 °C) PLMA chains induced chain mobility to the network structure which led to the complete scratch healing of the coating at 60 °C in five days due to furan-maleimide adduct formation. The storage modulus of the network polymer was found to be 3.7 × 104 Pa at the constant angular frequency of 5 rad/sec and strain of 0.5%. The regular reversal of storage (G′) and loss modulus (G″) was observed with repeated heating (40 to 110 °C) and cooling cycles (110 to 40 °C) at constant angular frequency and strain.
Synthesis of Two Epimers of Pseudopaline
Arnoux, Pascal,Cavelier, Florine,Cullia, Gregorio,Fanelli, Roberto,Voulhoux, Romé
, (2020/07/06)
Opines are a known group of compounds characterized by an elevated polarity. Recently, two new members of this class, staphylopine and pseudopaline, have been identified in Staphylococcus aureus and Pseudomonas aeruginosa, respectively. These molecules are metal chelators that contribute to the growth of bacteria in particularly metal-poor environment. Different evidences suggest that these molecules might have an important role in the development of pulmonary infections in humans. Considering the impact of P. aeruginosa infections in cystic fibrosis patients (prevalence up to 70 percent), pseudopaline has risen interest as potential source of new therapeutic intervention. We present herein a straightforward synthetic approach for the synthesis of the two epimers of pseudopaline. Starting from a chiral building block, we attribute the absolute configuration to the two obtained diasteroisomers.
GADOLINIUM BEARING PCTA-BASED CONTRAST AGENTS
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Page/Page column 29-30, (2020/03/02)
The present invention relates to the RRR/SSS pair of enantiomers of the of Gd(PCTA-tris-glutamic acid), the single enantiomers of the pair, the pharmaceutically acceptable salts thereof, their amide derivatives, and compositions comprising at least 50% of these compounds.
Strategies for the synthesis of HBGl3, a glutamic acid derived ligand bearing phenolic and azacarboxylate donor groups at the nitrogen atom
Mulla, Raminder S.,Walden, Melissa T.,Yufit, Dmitry S.,Desa, Tanya,Lurie-Luke, Elena,Williams, J.A. Gareth
supporting information, p. 6410 - 6420 (2017/09/29)
The development of a route applicable to the preparation of acyclic glutamic acid-based chelating ligands bearing two different auxiliary donor groups linked to the nitrogen atom by methylene spacers is described and applied to the synthesis of the new polydentate ligand HBGl3, the first example of such a structure. The synthesis is accomplished using a strategy employing reductive amination and t-butyl ester protected intermediates. The most basic pKa values for the HBGl3 ligand have been estimated via potentiometric and UV–Visible titration techniques.
Cobalt-bisoxazoline-catalyzed asymmetric kumada cross-coupling of racemic α-bromo esters with aryl grignard reagents
Mao, Jianyou,Liu, Feipeng,Wang, Min,Wu, Lin,Zheng, Bing,Liu, Shangzhong,Zhong, Jiangchun,Bian, Qinghua,Walsh, Patrick J.
supporting information, p. 17662 - 17668 (2015/02/02)
The first cobalt-catalyzed asymmetric Kumada cross-coupling with high enantioselectivity has been developed. The reaction affords a unique strategy for the enantioselective arylation of α-bromo esters catalyzed by a cobalt-bisoxazoline complex. A variety of chiral α-arylalkanoic esters were prepared in excellent enantioselectivity and yield (up to 97% ee and 96% yield). The arylated products were transformed into α-arylcarboxylic acids and primary alcohols without erosion of ee. The new enantioenriched α-arylpropionic esters synthesized herein are potentially useful in the development of nonsteroidal anti-inflammatory drugs. This method was conducted on gram-scale and applied to the synthesis of highly enantioenriched (S)-fenoprofen and (S)-ar-turmerone.
