Chaotropic Effects in Supercritical Fluid Chromatography via Ammonium Hydroxide in Water-rich Modifiers: Enabling Separation of Peptides and Highly Polar Pharmaceuticals at Preparative Scale.
- Jinchu Liu, A. Makarov, E. Regalado
- ChemistryAnalytical Chemistry
- 24 September 2019
This work introduces chaotropic effects in SFC separations using a non-traditional mobile phase mixture consisting of ammonium hydroxide combined with high water concentration in alcohol modifier and carbon dioxide to enable the widespread transition of SFC to domains that were previously considered out of its scope.
Electrochemical Synthesis of Hindered Primary and Secondary Amines via Proton-Coupled Electron Transfer.
- Dan Lehnherr, Yu-hong Lam, T. Rovis
- ChemistryJournal of the American Chemical Society
- 18 December 2019
Mechanistic insight based on DFT data, as well as cyclic voltammetry and NMR spectroscopy, suggests that a proton-coupled electron-transfer mechanism is operational as part of a hetero-biradical cross-Coupling of α-amino radicals and radicals derived from cyanoheteroarenes.
Extending the range of supercritical fluid chromatography by use of water-rich modifiers.
- Jinchu Liu, E. Regalado, I. Mergelsberg, C. Welch
- ChemistryOrganic and biomolecular chemistry
- 10 July 2013
Improved peak shape is obtained for a variety of glycosides and otherwise hydrophilic compounds when 5% water is added to the methanol co-solvent used in SFC separations, and examples of the use of this approach in preparative SFC purifications are presented.
Expanding the range of sub/supercritical fluid chromatography: Advantageous use of methanesulfonic acid in water-rich modifiers for peptide analysis.
- G. L. Losacco, Jimmy O. DaSilva, Jinchu Liu, E. Regalado, J. Veuthey, D. Guillarme
- MedicineJournal of Chromatography A
- 9 March 2021
Synthesis of [1,2,4]Triazolo[4,3-α]piperazines via Highly Reactive Chloromethyloxadiazoles
- J. Balsells, L. Dimichele, Jinchu Liu, M. Kubryk, K. Hansen, J. Armstrong
- Chemistry
- 17 February 2005
A concise, modular approach for the synthesis of [1,2,4]triazolo[4,3-α]piperazines via condensation of highly reactive chloromethyloxadiazoles with ethylenediamines is described. NMR studies of this…
Generic Enhanced Sub/Supercritical Fluid Chromatography: Blueprint for Highly Productive and Sustainable Separation of Primary Hindered Amines
- Jimmy O. DaSilva, Dan Lehnherr, E. Regalado
- Chemistry
- 25 March 2020
α,α-Diaryl primary amines are highly important chemical building blocks in agrochemical and pharmaceutical active ingredients. One of the limitations of current chromatographic methodologies for th...
Support of academic synthetic chemistry using separation technologies from the pharmaceutical industry.
- E. Regalado, M. Kozlowski, C. Welch
- ChemistryOrganic and biomolecular chemistry
- 12 March 2014
The use of state-of-the-art separation tools from the pharmaceutical industry for addressing intractable separation problems from academic synthetic chemistry is evaluated, showing fast and useful…
Highly diastereoselective heterogeneously catalyzed hydrogenation of enamines for the synthesis of chiral beta-amino acid derivatives.
- N. Ikemoto, D. Tellers, R. Tillyer
- Chemistry, BiologyJournal of the American Chemical Society
- 19 February 2004
Pure (Z)-enamines readily prepared from beta-ketoesters and amides using (S)-phenylglycine amide were hydrogenated with very high diastereoselectivities (up to 200:1) using heterogeneous catalysis.…
Total Synthesis of Chaetoglobin A via Catalytic, Atroposelective Oxidative Phenol Coupling.
- Houng Kang, Carilyn Torruellas, Jinchu Liu, M. Kozlowski
- Chemistry, BiologyOrganic Letters
- 12 September 2018
The first total synthesis of chaetoglobin A (1), which features a chiral axis between two identical highly oxygenated bicyclic cores, was successfully completed in 12 steps from 2,6-dimethoxytoluene.…
Convergent Kilo-Scale Synthesis of a Potent Renin Inhibitor for the Treatment of Hypertension
- Louis-Charles Campeau, S. Dolman, P. O'shea
- Chemistry
- 24 June 2011
Process research and development of a synthetic route towards a novel renin inhibitor (1) is described. The highly convergent synthetic route provided 1 in 15% yield on multikilogram scale with a…
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