17901-01-8Relevant articles and documents
Synthesis, biological evaluation, and molecular modeling studies of chiral chloroquine analogues as antimalarial agents
Kondaparla, Srinivasarao,Debnath, Utsab,Dola, Vasantha Rao,Sinha, Manish,Katti, Seturam B.,Soni, Awakash,Srivastava, Kumkum,Puri, Sunil K.
, (2019/01/05)
In a focused exploration, we designed, synthesized, and biologically evaluated chiral conjugated new chloroquine (CQ) analogues with substituted piperazines as antimalarial agents. In vitro as well as in vivo studies revealed that compound 7c showed potent activity (in vitro 50% inhibitory concentration, 56.98 nM for strain 3D7 and 97.76 nM for strain K1; selectivity index in vivo [up to at a dose of 12.5 mg/kg of body weight], 3,510) as a new lead antimalarial agent. Other compounds (compounds 6b, 6d, 7d, 7h, 8c, 8d, 9a, and 9c) also showed moderate activity against a CQ-sensitive strain (3D7) and superior activity against a CQ-resistant strain (K1) of Plasmodium falciparum. Furthermore, we carried out docking and three-dimensional quantitative structure-activity relationship (3D-QSAR) studies of all in-house data sets (168 molecules) of chiral CQ analogues to explain the structure-activity relationships (SAR). Our new findings specify the significance of the H-bond interaction with the side chain of heme for biological activity. In addition, the 3D-QSAR study against the 3D7 strain indicated the favorable and unfavorable sites of CQ analogues for incorporating steric, hydrophobic, and electropositive groups to improve the antimalarial activity.
Aqueous MW eco-friendly protocol for amino group protection
Nardi,Cano, N. Herrera,Costanzo,Oliverio,Sindona,Procopio
, p. 18751 - 18760 (2015/06/15)
In this paper a new catalyst-free and on-water method for protection of amines and amino acids with di-tert-butyl dicarbonate, 9-fluorenylmethoxycarbonyl chloride, acetyl chloride and tosyl chloride is presented. The protection can be realized in a few minutes under microwave-assistance. The reaction proved to be chemoselective in presence of ambident nucleophiles and water solution of di-tert-butyl carboxylic acid or chloride acid are the only wastes produced.
Lipopeptides from the tropical marine cyanobacterium symploca sp.
Mevers, Emily,Haeckl, F. P. Jake,Boudreau, Paul D.,Byrum, Tara,Dorrestein, Pieter C.,Valeriote, Frederick A.,Gerwick, William H.
, p. 969 - 975 (2014/05/20)
A collection of the tropical marine cyanobacterium Symploca sp., collected near Kimbe Bay, Papua New Guinea, previously yielded several new metabolites including kimbeamides A-C, kimbelactone A, and tasihalide C. Investigations into a more polar cytotoxic fraction yielded three new lipopeptides, tasiamides C-E (1-3). The planar structures were deduced by 2D NMR spectroscopy and tandem mass spectrometry, and their absolute configurations were determined by a combination of Marfeys and chiral-phase GC-MS analysis. These new metabolites are similar to several previously isolated compounds, including tasiamide (4), grassystatins (5, 6), and symplocin A, all of which were isolated from similar filamentous marine cyanobacteria.
Design, synthesis and evaluation of novel indole derivatives as AKT inhibitors
Yang, Dezhi,Wang, Peng,Liu, Jianzhen,Xing, Hualu,Liu, Yang,Xie, Wencheng,Zhao, Guisen
, p. 366 - 373 (2014/01/17)
Herein, we describe the discovery and synthesis of a new series of 1,2,4,7-tetra-substituted indole derivatives as novel AKT inhibitors by optimization of a weak hit methyl 4-(2-aminoethoxy)-1H-indole-2-carboxylate (1). Both representative compounds 6a and 6o exhibited the most potent inhibitory activities against AKT1, with inhibition rates of 72.5% and 78.6%, respectively, at concentrations of 10 nM. In addition, compounds 6a and 6o also potently inhibited the phosphorylation of the downstream GSK3 protein and displayed slightly better anti-proliferative activities in a prostate cancer cell line.
Catalytic methyl transfer from dimethylcarbonate to carboxylic acids
Ji, Yuan,Sweeney, Jessica,Zoglio, Jillian,Gorin, David J.
, p. 11606 - 11611 (2013/12/04)
Although methylation reactions are commonplace, currently used reagents are hazardous, toxic, and/or unstable. Dimethylcarbonate has been put forth as an inexpensive, nontoxic, and green potential methylating reagent. Herein we report a general, base-catalyzed methyl transfer from dimethylcarbonate to carboxylic acids. High selectivity for esterification is observed even in the presence of unprotected phenols, and the mild reaction conditions enable conservation of stereochemistry at epimerizable stereocenters. Isotope-labeling studies suggest a mechanism proceeding by direct methyl transfer from dimethylcarbonate to the substrate.
Design, synthesis, and applications of potential substitutes of t-Bu-phosphinooxazoline in Pd-catalyzed asymmetric transformations and their use for the improvement of the enantioselectivity in the Pd-catalyzed allylation reaction of fluorinated allyl enol carbonates
Belanger, Etienne,Pouliot, Marie-France,Courtemanche, Marc-Andre,Paquin, Jean-Francois
scheme or table, p. 317 - 331 (2012/02/15)
The design, synthesis, and applications of potential substitutes of t-Bu-PHOX in asymmetric catalysis is reported. The design relies on the incorporation of geminal substituents at C5 in combination with a substituent at C4 other than t-butyl (i-Pr, i-Bu, or s-Bu). Most of these new members of the PHOX ligand family behave similarly in terms of stereoinduction to t-Bu-PHOX in three palladium-catalyzed asymmetric transformations. Electronically modified ligands were also prepared and used to improve the enantioselectivity in the Pd-catalyzed allylation reaction of fluorinated allyl enol carbonates.
Universal peptidomimetics
Ko, Eunhwa,Liu, Jing,Perez, Lisa M.,Lu, Genliang,Schaefer, Amber,Burgess, Kevin
supporting information; scheme or table, p. 462 - 477 (2011/04/16)
This paper concerns peptidomimetic scaffolds that can present side chains in conformations resembling those of amino acids in secondary structures without incurring excessive entropic or enthalpic penalties. Compounds of this type are referred to here as minimalist mimics. The core hypothesis of this paper is that small sets of such scaffolds can be designed to analogue local pairs of amino acids (including noncontiguous ones) in any secondary structure; i.e., they are universal peptidomimetics. To illustrate this concept, we designed a set of four peptidomimetic scaffolds. Libraries based on them were made bearing side chains corresponding to many of the protein-derived amino acids. Modeling experiments were performed to give an indication of kinetic and thermodynamic accessibilities of conformations that can mimic secondary structures. Together, peptidomimetics based on these four scaffolds can adopt conformations that resemble almost any combination of local amino acid side chains in any secondary structure. Universal peptidomimetics of this kind are likely to be most useful in the design of libraries for high-throughput screening against diverse targets. Consequently, data arising from submission of these molecules to the NIH Molecular Libraries Small Molecule Repository (MLSMR) are outlined.
Efficient and selective cleavage of the t-butoxycarbonyl group from di-t-butylimidodicarbonate using catalytic bismuth(III) bromide in acetonitrile
Zheng, Jianlong,Yin, Biaolin,Huang, Wenming,Li, Xiaopeng,Yao, Hequan,Liu, Zhaogui,Zhang, Jiancun,Jiang, Sheng
scheme or table, p. 5094 - 5097 (2009/12/01)
Di-t-butylimidodicarbonates can be chemoselectively and efficiently deprotected to the corresponding mono-BOC-protected amines in high yields using a catalytic amount of bismuth(III) bromide in acetonitrile at room temperature. This method is mild and compatible with the presence of a wide range of functional and other protecting groups in the substrates, such as TBDMS, MOM and mono-BOC or Cbz-protected amines, etc. The method has advantages of ease of operation and use of nontoxic and inexpensive catalyst.
Development of a temporary marker for peptides
Sameiro,Goncalves,Maia, Hernani L.S.
, p. 1480 - 1485 (2007/10/03)
3-[(N,N-Dimethylaminophenyl)-4′-diazenyl]benzoic acid was coupled with several amino acid esters and the product acylated further with Boc. The material thus obtained was then submitted to cleavage by electrolysis and nucleophilic attack in order to evaluate the possibility of using this chromophore as a temporary marker.
Efficient and selective cleavage of t-butoxycarbonyl group from carbamates and amides by CeCl3·7H2O-NaI
Yadav,Subba Reddy,Reddy, K. Srinivasa
, p. 468 - 470 (2007/10/03)
A highly selective cleavage of the t-butoxycarbonyl group has been achieved in high yields using CeCl3·7H2O-NaI in acetonitrile at ambient temperature under neutral conditions. This method is mild and compatible with a wide range of
