- Antibody drug conjugates of cleavable amino-benzoyl-maytansinoids
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ADCs based on the natural product maytansine have been successfully employed clinically. In a previous report, ADCs based on hydrophilic non-cell permeable maytansinoids was presented. The authors in this report further explore the maytansine scaffold to
- Carosso, Serena,Chen, Zhaoyuan,Delfino, Frank,Hickey, Carlos,Kelly, Marcus,Kirshner, Jessica R.,Kunz, Arthur,Makonnen, Sosina,Mao, Shu,Markotan, Thomas,Navarro, Elizabeth,Nittoli, Thomas,Olson, William,Papadopoulos, Nicholas,Shan, Jing,Spink, Jan,Thurston, Gavin,Zhao, Feng
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- STAT INHIBITORY COMPOUNDS AND COMPOSITIONS
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Provided herein are compounds and pharmaceutical compositions comprising said compounds that are useful for the inhibition of Signal Transducer and Activator of Transcription 5a and 5b (STAT5). Furthermore, the subject compounds and compositions are usefu
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Paragraph 0260
(2021/09/11)
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- Total Synthesis and Biological Assessment of Novel Albicidins Discovered by Mass Spectrometric Networking
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Natural products represent an important source of potential novel antimicrobial drug leads. Low production by microorganisms in cell culture often delays the structural elucidation or even prevents a timely discovery. Starting from the anti-Gram-negative antibacterial compound albicidin produced by Xanthomonas albilineans, we describe a bioactivity-guided approach combined with non-targeted tandem mass spectrometry and spectral (molecular) networking for the discovery of novel antimicrobial compounds. We report eight new natural albicidin derivatives, four of which bear a β-methoxy cyanoalanine or β-methoxy asparagine as the central α-amino acid. We present the total synthesis of these albicidins, which facilitated the unambiguous determination of the (2 S,3 R)-stereoconfiguration which is complemented by the assessment of the stereochemistry on antibacterial activity.
- von Eckardstein, Leonard,Petras, Daniel,Dang, Tam,Cociancich, Stéphane,Sabri, Souhir,Gr?tz, Stefan,Kerwat, Dennis,Seidel, Maria,Pesic, Alexander,Dorrestein, Pieter C.,Royer, Monique,Weston, John B.,Süssmuth, Roderich D.
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supporting information
p. 15316 - 15321
(2017/10/20)
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- Biologically Useful Chelators That Take Up Ca(2+) upon Illumination
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Two approaches were explored toward the goal of synthesizing physiologically useful Ca(2+)-selective chelators whose Ca(2+) affinities increase markedly upon photolysis.In the first approach, the known Ca(2+)-selective chelator 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) was masked with a variety of photoremovable protecting groups on one of its four carboxyl groups, reducing its affinity for Ca(2+) to ca. 1E5 M-1.Upon irradiation around 356 nm, free chelator with an affinity constant ca. 1E7 M-1 was regenerated but with very low quantumefficiencies (-1.Photochemical rearrangement of the diazoacetyl group converted it into an electron-donating carboxymethyl group, causing the Ca(2+) affinity to increase 30-fold to 1.4E7 M-1.The photolysis of Ca(2+)-free diazo-2 had a quantum efficiency with 365-nm light (λmax 370 nm, ε ca. 22000 M-1cm-1) of ca. 0.03 and generated the high-affinity chelator with rate constants of 2300 s-1 after a flash.Ca(2+) was then bound with association and dissociation rate constants of 8.0E8 M-1s-1 and 58 s-1, respectively.Diazo-2 was incorporated into rat fibroblasts either by microinjection or by incubation as the membrane-permeable, enzymatically labile tetrakis(acetoxymethyl) ester and, when flash-photolyzed, caused a drop in intracellular free to or below resting values of ca. 1E-7 M.An even larger increase in affinity(1600-fold) was obtained by substituting both phenyl rings of BAPTA with diazoacetyl substituents.Therefore, these chelators can be used to generate controlled fast decrements in intracellular free to mimic or ablate a host of important cellular responses, especially in nerve and muscle.
- Adams, S. R.,Kao, J. P. Y.,Tsien, R. Y.
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p. 7957 - 7968
(2007/10/02)
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