A step-economic and one-pot access to chiral C<sup>α</sup>-tetrasubstituted α-amino acid derivatives <i>via</i> a bicyclic imidazole-catalyzed direct enantioselective <i>C</i>-acylation
Cα-Tetrasubstituted α-amino acids are ubiquitous and unique structural units in bioactive natural products and pharmaceutical compounds. The asymmetric synthesis of these molecules has attracted a lot of attention, but a more efficient method is still greatly desired. Here we describe the first sequential four-step acylation reaction for the efficientsynthesis of chiral Cα-tetrasubstituted α-amino acid derivatives
Herein, two novel multifunctional releasablephotoaffinitylinkers were developed for effective and transient tracking interacting proteins with the overall objective of understanding their in vivo biological functions in real-time. These linkers could be used for the chemical modification of protein under moderate experimental conditions to form protein photoaffinity probes. These probes incorporated
Synthesis, Spectral and Antimicrobial Studies on some Newer Imidazole Analogs
作者:Rajiv Dahiya
DOI:10.3797/scipharm.0803-04
日期:——
A novel series of 3,5-diiodo-4-(2-methyl-1H-imidazol-5-yl)benzoic acid analogs of amino acids, dipeptides and tripeptides was synthesized by using dicyclohexylcarbodiimide and diisopropylcarbodiimide (DCC/DIPC) as coupling agents and triethylamine (TEA) as base. Structures of all the newly synthesized compounds were confirmed by elemental analysis and IR, 1H NMR, 13C NMR and mass spectral data. Imidazolopeptides were investigated for their antimicrobial activity and some of newly synthesized compounds 2c, 2d, 2h and their hydrolyzed analogs 3b, 3d exhibited potent bioactivity against pathogenic fungi Candida albicans and dermatophytes Trichophyton mentagrophytes and Microsporum audouinii with MIC values of 12.5-6 μg/ml, as compared to the reference drug - griseofulvin. In addition, moderate activity against gram negative bacteria Pseudomonas aeruginosa and Klebsiella pneumoniae was also observed for synthesized imidazolopeptides.
Synthesis and Biological Activity of Peptide Derivatives of Iodoquinazolinones/Nitroimidazoles
作者:Rajiv Dahiya、Anil Kumar、Rakesh Yadav
DOI:10.3390/molecules13040958
日期:——
to afford the corresponding acid derivatives 5ba-da and 6ea-ga. All peptide derivatives were assayed for antimicrobial and anthelmintic activities against eight pathogenic microbes and three earthworm species. Among the tested compounds, 5e, 5d, 6e and their hydrolyzed analogs 5da and 6ea exhibited higher antimicrobial activity against Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans
Copper(I)-Mediated Denitrogenative Macrocyclization for the Synthesis of Cyclic α<sub>3</sub>
β-Tetrapeptide Analogues
作者:Chun-Chi Chen、Sheng-Fu Wang、Yung-Yu Su、Yuya A. Lin、Po-Chiao Lin
DOI:10.1002/asia.201700339
日期:2017.6.19
α3β‐tetrapeptide analogues that contain important biological properties and results in rich structural information being obtained for conformational studies. With the success of this copper(I)‐catalyzed macrocyclization, two histone deacetylase inhibitor analogues consisting of the cyclic α3β‐tetrapeptide framework have been successfully synthesized.