6330-15-0Relevant academic research and scientific papers
Chiral recognition of carboxylates by a static library of thiourea receptors with amino acid arms
Ulatowski, Filip,Jurczak, Janusz
, p. 4235 - 4243 (2015/05/13)
Chiral recognition is based on a large network of very subtle interactions whose outcome is difficult to predict. A combinatorial approach is therefore the most suitable to search for the most efficient receptor and obtain a structure-enantioselectivity correlation. We synthesized a set of 12 receptors constructed with 1,9-diaminoantracene and α-amino acid esters, linked via thiourea groups. The association constants and enantioselectivities for the complexes with mandelate and N-acetylphenylalanine were determined by competitive NMR titrations. Association constants quite regularly depend on the substituents in the receptor structure, but the distribution of enantioselectivities across the library could not easily be rationalized.
Antimicrobial toxicity studies of ionic liquids leading to a 'hit' MRSA selective antibacterial imidazolium salt
Coleman, Deborah,Spulak, Marcel,Garcia, M. Teresa,Gathergood, Nicholas
body text, p. 1350 - 1356 (2012/06/16)
Imidazolium salts can be classed as surfactants, detergents, ionic liquids, reagents, catalysts or solvents. A study of the toxicity and ecotoxicity of these salts yields valuable information for their use as pharmaceuticals as well as impact on the environment. Our approach to screen a series of chiral imidazolium salts for toxicity to bacteria and fungi, including clinical pathogen strains, has led to the identification of a 'hit' MRSA selective antimicrobial compound. Preliminary structure-activity-relationship (SAR) information (required position of l-phenylalanine and l-valine group) is also elucidated within this first generation of compounds. Conversely, most of the imidazolium salts were nontoxic (IC95 > 2 mM) to the 12 fungi strains and 8 bacteria strains screened, and we propose that they are suitable candidates for 'green chemistry' applications. Ecotoxicity studies (Biodegradation ISO 14593 'CO2 Headspace Test') of two bromide ionic liquids containing l-phenylalanine residues indicate that these ionic liquids passed the test (>60% in 28 days) and classed as readily biodegradable.
A simple synthesis of chiral macrocyclic tetraamides derived from α-amino acids
Zielinski, Tomasz,Achmatowicz, Michal,Jurczak, Janusz
, p. 2053 - 2059 (2007/10/03)
Bisamidation of oxalyl chloride using four L-α-amino acid esters afforded chiral diesters which were reacted with three α,ω-diamines under high-pressure conditions (10 kbar) to give macrocyclic tetramides of C2-symmetry.
N-cholyl amino acid alkyl esters - A novel class of organogelators
Willemen, Hendra M.,Vermonden, Tina,Marcelis, Antonius T. M.,Sudhoelter, Ernst J. R.
, p. 2329 - 2335 (2007/10/03)
Several N-cholyl amino acid alkyl esters were found to act as novel, potent organogelators for aromatic solvents and cyclohexene. These novel organogelators afford stable, transparent, and thermoreversible gels. Modification of the molecular structure and IR measurements show that gelation takes place by means of a hydrogen-bonded network and involves at least the amide bond and several hydroxy groups of the cholic acid component. The chiral center of the amino acid component seems to play an important role in gelation. Although a wide variety of derivatives display gelation behavior, a small change in molecular structure can have a dramatic effect on the gelling capability. Electron microscopy reveals a fibrous structure in the gels. Differential scanning calorimetry shows several transitions in the melting behavior of the gels.
