- A Diverse Library of Chiral Cyclopropane Scaffolds via Chemoenzymatic Assembly and Diversification of Cyclopropyl Ketones
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Chiral cyclopropane rings are key pharmacophores in pharmaceuticals and bioactive natural products, making libraries of these building blocks a valuable resource for drug discovery and development campaigns. Here, we report the development of a chemoenzymatic strategy for the stereoselective assembly and structural diversification of cyclopropyl ketones, a highly versatile yet underexploited class of functionalized cyclopropanes. An engineered variant of sperm whale myoglobin is shown to enable the highly diastereo- and enantioselective construction of these molecules via olefin cyclopropanation in the presence of a diazoketone carbene donor reagent. This biocatalyst offers a remarkably broad substrate scope, catalyzing this reaction with high stereoselectivity across a variety of vinylarene substrates as well as a range of different α-aryl and α-alkyl diazoketone derivatives. Chemical transformation of these enzymatic products enables further diversification of these molecules to yield a collection of structurally diverse cyclopropane-containing scaffolds in enantiopure form, including core motifs found in drugs and natural products as well as novel structures. This work illustrates the power of combining abiological biocatalysis with chemoenzymatic synthesis for generating collections of optically active scaffolds of high value for medicinal chemistry and drug discovery.
- Nam, Donggeon,Steck, Viktoria,Potenzino, Robert J.,Fasan, Rudi
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supporting information
p. 2221 - 2231
(2021/02/16)
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- Methods and compositions for selectin inhibition
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The present invention relates to the field of anti-inflammatory substances, and more particularly to novel compounds that act as antagonists of the mammalian adhesion proteins known as selectins. In some embodiments, methods for treating selectin mediated disorders are provided which include administration of compound of Formula I: wherein the constituent variables are defined herein.
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Page/Page column 14
(2008/06/13)
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- Antiangiogenic and antitumor agents: Design, synthesis, and evaluation of novel 2-amino-4-(3-bromoanilino)-6-benzylsubstituted pyrrolo[2,3-d]pyrimidines as inhibitors of receptor tyrosine kinases
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Several different classes of growth factor receptors containing tyrosine kinases (RTK) are directly or indirectly involved in angiogenesis. Inhibition of these RTKs has provided a new paradigm in the treatment of tumors by restricting their growth and metastasis. We have designed, synthesized and evaluated eleven novel 2-amino-4-(3-bromoanilino)-6-substituted benzyl pyrrolo[2,3-d]pyrimidines as the first in a series of RTK inhibitors. These analogues were synthesized from appropriate α-bromomethylbenzyl ketones by cyclocondensation with 2,6-diamino-4-pyrimidone to afford the 2-amino-4-oxo-6-substituted benzyl pyrrolo[2,3-d]pyrimidines. Chlorination of the 4-position followed by displacement with 3-bromoaniline afforded the target compounds. In some instances, the 2-amino moiety of the pyrrolo[2,3-d] pyrimidines was protected prior to the chlorination and displacement followed by deprotection. The compounds were evaluated as inhibitors of vascular endothelial growth factor receptors VEGFR-2 (Flk-1, KDR) and VEGFR-1 (Flt-1); epidermal growth factor receptor (EGFR); and platelet-derived growth factor receptor-β (PDGFR-β). Selected compounds were also evaluated against the growth of A431 cells (which overexpress EGFR) in culture and as inhibitors of angiogenesis in the chicken embryo chorioallantonic membrane (CAM) assay. In each evaluation, a known standard compound was used as a comparison. Of the 11 analogues, five were more potent or equipotent as compared to standard compounds against the growth factor receptors. Two analogues showed superior inhibition of A431 cells in culture compared to the standard compounds. Three analogues were equipotent with the standard compound in the CAM assay and four of the analogues were dual inhibitors of RTKs. The structure-activity relationship for inhibition of different RTKs was quite distinct and different, and for VEGFR-2 and EGFR diametrically opposite. The inhibitory data against the RTKs in this study demonstrates that variation of the substituent(s) in the benzyl ring of these 2-amino-4-anilino 6-benzyl pyrrolo[2,3-d]pyrimidines does indeed control both the potency and specificity of inhibitory activity against RTKs.
- Gangjee, Aleem,Yang, Jie,Ihnat, Michael A.,Kamat, Shekhar
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p. 5155 - 5170
(2007/10/03)
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