35696-87-8Relevant academic research and scientific papers
Monodentate Transient Directing Group Enabled Pd-Catalyzed Ortho-C-H Methoxylation and Chlorination of Benzaldehydes
Li, Feng,Zhou, Yirong,Yang, Heng,Wang, Ziqi,Yu, Qinqin,Zhang, Fang-Lin
supporting information, p. 3692 - 3695 (2019/05/24)
We report Pd-catalyzed ortho-C-H methoxylation and chlorination of benzaldehydes by employing monodentate transient directing groups (TDGs) as an alternative strategy to bidentate TDGs. More importantly, a single crystal of benzaldehyde imine ortho-cyclopalladium intermediate was successfully obtained, and its structure was unambiguously determined by X-ray diffraction, which clearly showed that it was a binuclear palladium species bridged by a pyridone ligand. The utility of this approach was further demonstrated through the synthesis of key intermediates of natural products and drugs.
Pd-Catalyzed, ortho C-H Methylation and Fluorination of Benzaldehydes Using Orthanilic Acids as Transient Directing Groups
Chen, Xiao-Yang,Sorensen, Erik J.
supporting information, p. 2789 - 2792 (2018/03/08)
The direct, Pd-catalyzed ortho C-H methylation and fluorination of benzaldehydes have been accomplished using commercially available orthanilic acids as transient directing groups. In these reactions, the 1-fluoro-2,4,6-trimethylpyridinium salts can be either a bystanding F+ oxidant or an electrophilic fluorinating reagent. An X-ray crystal structure of a benzaldehyde ortho C-H palladation intermediate was obtained using triphenylphosphine as the stabilizing ligand.
X-ray Characterization and Structure-Based Optimization of Striatal-Enriched Protein Tyrosine Phosphatase Inhibitors
Witten, Michael R.,Wissler, Lisa,Snow, Melanie,Geschwindner, Stefan,Read, Jon A.,Brandon, Nicholas J.,Nairn, Angus C.,Lombroso, Paul J.,K?ck, Helena,Ellman, Jonathan A.
, p. 9299 - 9319 (2017/11/30)
Excessive activity of striatal-enriched protein tyrosine phosphatase (STEP) in the brain has been detected in numerous neuropsychiatric disorders including Alzheimer's disease. Notably, knockdown of STEP in an Alzheimer mouse model effected an increase in the phosphorylation levels of downstream STEP substrates and a significant reversal in the observed cognitive and memory deficits. These data point to the promising potential of STEP as a target for drug discovery in Alzheimer's treatment. We previously reported a substrate-based approach to the development of low molecular weight STEP inhibitors with Ki values as low as 7.8 μM. Herein, we disclose the first X-ray crystal structures of inhibitors bound to STEP and the surprising finding that they occupy noncoincident binding sites. Moreover, we utilize this structural information to optimize the inhibitor structure to achieve a Ki of 110 nM, with 15-60-fold selectivity across a series of phosphatases.
Diverse ortho-C(sp2)-H functionalization of benzaldehydes using transient directing groups
Liu, Xi-Hai,Park, Hojoon,Hu, Jun-Hao,Hu, Yan,Zhang, Qun-Liang,Wang, Bao-Long,Sun, Bing,Yeung, Kap-Sun,Zhang, Fang-Lin,Yu, Jin-Quan
supporting information, p. 888 - 896 (2017/05/16)
Pd-catalyzed C-H functionalizations promoted by transient directing groups remain largely limited to C-H arylation only. Herein, we report a diverse set of ortho-C(sp2)-H functionalizations of benzaldehyde substrates using the transient directing group strategy. Without installing any auxiliary directing group, Pd(II)-catalyzed C-H arylation, chlorination, bromination, and Ir(III)-catalyzed amidation, could be achieved on benzaldehyde substrates. The transient directing groups formed in situ via imine linkage can override other coordinating functional groups capable of directing C-H activation or catalyst poisoning, significantly expanding the scope for metal-catalyzed C-H functionalization of benzaldehydes. The utility of this approach is demonstrated through multiple applications, including late-stage diversification of a drug analogue.
Pd-Catalyzed Ortho C-H Hydroxylation of Benzaldehydes Using a Transient Directing Group
Chen, Xiao-Yang,Ozturk, Seyma,Sorensen, Erik J.
supporting information, p. 6280 - 6283 (2017/12/08)
The direct Pd-catalyzed ortho C-H hydroxylation of benzaldehydes was achieved using 4-chloroanthranilic acid as the transient directing group, 1-fluoro-2,4,6-trimethylpyridnium triflate as the bystanding oxidant, and p-toluenesulfonic acid as the putative oxygen nucleophile. The unusual C-H chlorination and polyfluoroalkoxylation reactions signaled the importance of external nucleophiles to the outcome of Pd(IV) reductive eliminations.
Anti-MRSA cephems. Part 3: additional C-7 acid derivatives.
Springer, Dane M,Luh, Bing Yu,Goodrich, Jason T,Bronson, Joanne J
, p. 281 - 291 (2007/10/03)
Twenty-seven novel cephalosporin derivatives with activity against methicillin-resistant Staphylococcus aureus (MRSA) are described. The compounds contain novel acid moieties at C-7 that were synthesized using nucleophilic aromatic substitution reactions and Stille couplings. The most interesting compound (6) displayed an MIC(90) against MRSA of 3.7 microg/mL, and an average PD(50) of 3.9 mg/kg.
Cephalosporin derivatives
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, (2008/06/13)
The present invention provides a novel series of cephem derivatives of the general formula I wherein R1, R2, R3, R5, R6, R7, A, L1, X, n and n′ are as defined herein above. The compounds of formula I are antibacterial agents useful in the treatment of infections in humans and other animals caused by a variety of gram-positive bacteria, particularly methicillin-resistant Staphylococcus aureus. Also included in the invention are processes for preparing the compounds of formula I and pharmaceutical compositions containing said compounds in combination with pharmaceutically acceptable carriers, diluents or excipients.
