Design,Synthesis, and Anti-Proliferative Activity of Some New Quinoxaline-1,3,4-oxadiazole Sulfonamide Hybrids

Russian Journal of General Chemistry - In the current study, some new quinoxaline linked 1,3,4-oxadiazole sulfonamide hybrids have been designed, synthesized and characterized by IR, 1H and 13C...     

Rapid Characterization of Molecular Diffusion by NMR Spectroscopy

An NMR‐based approach for rapid characterization of translational diffusion of molecules has been developed. Unlike the conventional method of acquiring a series of 2D ¹³C and ¹H spectra, the proposed approach involves a single 2D NMR spectrum, which can be acquired in minutes. Using this method, it was possible to detect the presence of intermediate oligomeric species of diphenylalanine in solution during the process of its self‐assembly to form nanotubular structures.     

A multielectrode microcompartment culture platform for studying signal transduction in the nervous system

This paper describes the design, fabrication, and characterization of a microfabricated compartmented culture system (micro-CCS) useful for electrophysiological signaling studies in cultured neurons. The focus of the paper is the process of interfacing the micro-CCS with cultured neurons and to demonstrate the applicability of the system for biochemical-mediated electrophysiological studies. Moreover, we show that we can record action potentials from cultured neurons through the extracellular compartmented application of elevated levels of K(+) ions. Finally, we show that we can isolate the electrophysiological effects of the sodium channel blocker tetrodotoxin in one of the compartments of a two compartment culture while recording electrophysiological data from both compartments.     

Design,Synthesis, Antitubercular and Antibacterial Activities of 1,3,5-Triazinyl Carboxamide Derivatives and In Silico Docking Studies

Russian Journal of General Chemistry - A series of novel N-{2-fluoro-6-[(4,6-dimethoxy-1,3,5-triazin-2-yl)methyl]phenyl} carboxamide derivatives has been synthesized, and their molecular structures...     

A new synthetic route to oxazole and pyrrole 2-deoxy-C-ribosides

The synthesis of oxazole and pyrrole 3-carbethoxy/3-arylsulfonyl d and l-2-deoxyribosides by TosMIC addition/cyclization on d and l-2-deoxyribo-1-carboxaldehyde and unsaturated esters in moderate to good yields is reported.     

Synthetic studies toward mannopeptimycin-E: synthesis of the O-linked tyrosine 1,4-alpha,alpha-manno,manno-pyranosyl pyranoside

[structure: see text] The enantioselective synthesis of the C-4' acylated 1,4-alpha,alpha-manno,manno-disaccharide fragment of mannopeptimycin-E has been achieved in seven steps from d-tyrosine. The route relies upon diastereoselective palladium-catalyzed glycosylation, diastereoselective reduction, and diastereoselective bis-dihydroxylation. The efficiency of the synthesis is demonstrated by the high overall yield (37%) and the preparation of various analogues.     

Synthesis of second-generation sansalvamide A derivatives: novel templates as potential antitumor agents

We report the synthesis of 34 second-generation Sansalvamide A derivatives. San A derivatives have unique anticancer properties and target multiple cancers, including colon, pancreatic, breast, prostate, and melanoma. As novel templates, the derivatives described herein explore the role of stereochemistry, amide bond geometry, transannular hydrogen bonding, and polarity on antitumor potency. Testing the chemotherapeutic activity of these derivatives against multiple cancer cell lines will provide clear structural motifs and identify conformational space that is important for cytotoxicity. The 34 compounds presented are divided into six series, where five series involve the insertion of D-amino acids in conjunction with four structural features at each of the five positions of the macrocycle. The sixth series involves comparison between all L- and all D-amino acid derivatives with N-methyls placed at each position around the macrocyclic core. The four structural features explored in conjunction with D-amino acids include N-methyl amino acids, aromatic amino acids, polar amino acids, and hydrophobic alkyl amino acids.     

De novo synthesis of oligosaccharides using a palladium-catalyzed glycosylation reaction

The natural all d- and/or unnatural all l-1,4- and 1,6-oligosaccharides were synthesized from furan alcohols using a palladium-catalyzed glycosylation reaction. The 1,4- and 1,6-alpha-manno-disaccharides were achieved in seven total steps starting from chiral furan alcohols. Similarly, 1,4- and 1,6-alpha-manno-trisaccharides were also synthesized in nine total steps. Key to the overall efficiency of this process was the use of highly diastereoselective palladium-catalyzed glycosylations, reductions, and dihydroxylations.     

A palladium-catalyzed glycosylation reaction: the de novo synthesis of natural and unnatural glycosides

A highly stereoselective and sterospecific palladium-catalyzed glycosylation reaction of a variety of alcohols is reported. The reaction selectively converts alpha-2-substituted 6-carboxy-2H-pyran-3(6H)-ones into alpha-2-substituted 6-alkoxy-2H-pyran-3(6H)-ones with complete retention of configuration and similarly converts the pyranones with beta-carboxy groups into pyranones with beta-alkoxy groups. The reaction works equally well with both amino acid- and carbohydrate-based alcohols. To demonstrate the utility of this process for carbohydrate chemistry several of the products were selectively converted into alpha-manno-pyranosides in two additional steps. Because the 2-substituted 6-carboxy-2H-pyran-3(6H)-ones are prepared by asymmetric synthesis, this reaction can be used for the preparation of either d- or l-pyranones.