13 research outputs found
The syntheses of novel indicators and materials for chiral separation
The colorimetric properties of resorcinarene solutions had not been fully investigated since von Baeyer\u27s initial synthesis. We find that the solutions containing resorcinarene macrocycles develop color upon heating or standing. In the presence of saccharides, these solutions exhibit significant color changes which are readily observable by visual inspection. We determined that the solution color is due to macrocycle ring opening and oxidation. The optical responses to saccharides are due to complexation of the sugar with the acyclic chromophores. We have applied these mechanistic insights towards the challenging problems of the visual detection of saccharides and other important biologically analytes. In addition, we also report the first single crystal X-ray crystal structure determination of a rarely observed diamond resorcinarene stereoisomer. The visual sensing of saccharides is of importance to medical diagnostics and industry. The synthesis of the diamine tripod and the diamine fluorescein compounds will be presented and their application towards the detection of saccharides and biomolecules of interest will be discussed. In addition to this, the synthesis of a new cationic chiral surfactant, the l-arginine methyl ester, for use in chiral separations will also be presented
Trimethylsulfonium Methanesulfonate
In the title compound, C3H9S+.CH3O3S-, a thermal decomposition product of dimethyl sulfoxide, both cation and anion lie on mirror planes. In the cation, the S atom lies 0.792 (2) 脜 out of the plane defined by the three C atoms, with S-C distances of 1.781 (2) and 1.786 (3) 脜. In the anion, the S-O distances are 1.4556 (14) and 1.4646 (19) 脜, and the S-C distance is 1.759 (3) 脜
The Science Performance of JWST as Characterized in Commissioning
This paper characterizes the actual science performance of the James Webb
Space Telescope (JWST), as determined from the six month commissioning period.
We summarize the performance of the spacecraft, telescope, science instruments,
and ground system, with an emphasis on differences from pre-launch
expectations. Commissioning has made clear that JWST is fully capable of
achieving the discoveries for which it was built. Moreover, almost across the
board, the science performance of JWST is better than expected; in most cases,
JWST will go deeper faster than expected. The telescope and instrument suite
have demonstrated the sensitivity, stability, image quality, and spectral range
that are necessary to transform our understanding of the cosmos through
observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures;
https://iopscience.iop.org/article/10.1088/1538-3873/acb29
Chromophore formation in resorcinarene solutions and the visual detection of mono- and oligosaccharides
The colorimetric properties of resorcinarene solutions had not been investigated since Baeyer\u27s initial synthesis. We recently reported that solutions containing resorcinarene macrocycles develop color upon heating or standing. In the presence of saccharides, these solutions exhibit significant color changes which are easily seen. We herein present strong evidence that the solution color is due to macrocycle ring opening and oxidation. The optical responses to saccharides are due to complexation of the sugar with the acyclic chromophores. We apply these mechanistic insights toward the challenging problem of the visual detection of neutral oligosaccharides by simple chromogens. In addition, we also report the first single-crystal X-ray crystal structure determination of a rarely observed diamond resorcinarene stereoisomer