A small, axially chiral diacid was designed with chiral memory based on restricted rotation. Heat... more A small, axially chiral diacid was designed with chiral memory based on restricted rotation. Heating a racemic sample with a chiral alkaloid led to an enantiomeric excess of up to 40% ee. The guest-induced chirality was preserved on cooling to rt, which was maintained even in the absence of guest (t(1/2) = 14y). The chiral enrichment process was also reversible, allowing the diacid to be used as a chiral switch.
Journal of the American Chemical Society, Jan 12, 2015
A new series of molecular torsion balances were designed to measure the strength of individual Ag... more A new series of molecular torsion balances were designed to measure the strength of individual Ag-π interactions in solution. The formation of a well-defined intramolecular Ag-π interaction in these model systems was verified by X-ray crystallography and 1H NMR. The strength of the intramolecular Ag-π interaction in solution was found to stabilizing in nature and quantified to be -1.34 to -2.6 kcal/mol using a double mutant cycle analysis. The Ag-π interaction was also found to be very sensitive to changes in geometry or solvent environment.
An eight channel molecularly imprinted polymer sensor array was prepared that was able to differe... more An eight channel molecularly imprinted polymer sensor array was prepared that was able to differentiate six different aryl amine analytes, including diastereomers with 94% accuracy.
... AH Hoveyda, Dr. BM Cole, Dr. KD Shimizu. ... Da die Reaktionen durch die Dipeptid-Schiff-Base... more ... AH Hoveyda, Dr. BM Cole, Dr. KD Shimizu. ... Da die Reaktionen durch die Dipeptid-Schiff-Basen beschleunigt wer-den[71, sollten eventuell auftretende Nebenprodukte der Ligan-den-Festphasensynthese kein ernstes Hindernis fur eine genaue Untersuchung sein, denn die ...
... Ken D. Shimizu, Bridget M. Cole, Clinton A. Krueger, Kevin W. Kuntz, Marc L. Snapper* und Ami... more ... Ken D. Shimizu, Bridget M. Cole, Clinton A. Krueger, Kevin W. Kuntz, Marc L. Snapper* und Amir H. Hoveyda* ... Unsere Methode weist gegenuber traditionelleren Verfahren zur Entdeckung chiraler Liganden eine Reihe von Vorteilen auf: 1) Die Suche kann auf einem festen ...
The majority of binding models that have been applied to molecularly imprinted polymers (MIPs) ha... more The majority of binding models that have been applied to molecularly imprinted polymers (MIPs) have been homogeneous models. MIPs, on the other hand, are heterogeneous materials containing binding sites with a wide array of binding affinities and selectivities. Demonstrated is that the binding behavior of MIPs can be accurately modeled by the heterogeneous Langmuir-Freundlich (LF) isotherm. The applicability of the LF isotherm to MIPs was demonstrated using five representative MIPs from the literature, including both homogeneous and heterogeneous MIPs. Previously, such comparisons required the use of several different binding models and analyses, including the Langmuir model, the Freundlich model, and numerical approximation techniques. In contrast, the LF model enabled direct comparisons of the binding characteristics of MIPs that have very different underlying distributions and were measured under different conditions. The binding parameters can be calculated directly using the LF fitting coefficients that yield a measure of the total number of binding sites, mean binding affinity, and heterogeneity. Alternatively, solution of the Langmuir adsorption integral for the LF model enabled direct calculation of the corresponding affinity spectrum from the LF fitting coefficients from a simple algebraic expression, yielding a measure of the number of binding sites with respect to association constant Finally, the ability of the LF isotherm to model MIPs suggests that a unimodal heterogeneous distribution is an accurate approximation of the distribution found in homogeneous and heterogeneous MIPs.
A large bis-urea macrocycle was synthesized and assembled into columnar nanotubes containing a si... more A large bis-urea macrocycle was synthesized and assembled into columnar nanotubes containing a sizable cavity. This purely organic nanotube is held together primarily by hydrogen bonding and yet shows remarkable thermal stability up to 180 degrees C in the presence and absence of acetic acid guest. This enables the nanotube to be used as reusable organic zeolite.
... Convergent Functional Groups. 15. Synthetic and Structural Studies of Large and Rigid Molecul... more ... Convergent Functional Groups. 15. Synthetic and Structural Studies of Large and Rigid Molecular Clefts Ken D. Shimizu, Torin M. Dewey, and J. Rebek, Jr.' ... SOC. 1987, 109, 65496551. (e) Galln, A.; Andreu, D.; Echavarren, AM; Prados, P.; de Mendoza, J. J. Am. Chem. Soc. ...
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
A small, axially chiral diacid was designed with chiral memory based on restricted rotation. Heat... more A small, axially chiral diacid was designed with chiral memory based on restricted rotation. Heating a racemic sample with a chiral alkaloid led to an enantiomeric excess of up to 40% ee. The guest-induced chirality was preserved on cooling to rt, which was maintained even in the absence of guest (t(1/2) = 14y). The chiral enrichment process was also reversible, allowing the diacid to be used as a chiral switch.
Journal of the American Chemical Society, Jan 12, 2015
A new series of molecular torsion balances were designed to measure the strength of individual Ag... more A new series of molecular torsion balances were designed to measure the strength of individual Ag-π interactions in solution. The formation of a well-defined intramolecular Ag-π interaction in these model systems was verified by X-ray crystallography and 1H NMR. The strength of the intramolecular Ag-π interaction in solution was found to stabilizing in nature and quantified to be -1.34 to -2.6 kcal/mol using a double mutant cycle analysis. The Ag-π interaction was also found to be very sensitive to changes in geometry or solvent environment.
An eight channel molecularly imprinted polymer sensor array was prepared that was able to differe... more An eight channel molecularly imprinted polymer sensor array was prepared that was able to differentiate six different aryl amine analytes, including diastereomers with 94% accuracy.
... AH Hoveyda, Dr. BM Cole, Dr. KD Shimizu. ... Da die Reaktionen durch die Dipeptid-Schiff-Base... more ... AH Hoveyda, Dr. BM Cole, Dr. KD Shimizu. ... Da die Reaktionen durch die Dipeptid-Schiff-Basen beschleunigt wer-den[71, sollten eventuell auftretende Nebenprodukte der Ligan-den-Festphasensynthese kein ernstes Hindernis fur eine genaue Untersuchung sein, denn die ...
... Ken D. Shimizu, Bridget M. Cole, Clinton A. Krueger, Kevin W. Kuntz, Marc L. Snapper* und Ami... more ... Ken D. Shimizu, Bridget M. Cole, Clinton A. Krueger, Kevin W. Kuntz, Marc L. Snapper* und Amir H. Hoveyda* ... Unsere Methode weist gegenuber traditionelleren Verfahren zur Entdeckung chiraler Liganden eine Reihe von Vorteilen auf: 1) Die Suche kann auf einem festen ...
The majority of binding models that have been applied to molecularly imprinted polymers (MIPs) ha... more The majority of binding models that have been applied to molecularly imprinted polymers (MIPs) have been homogeneous models. MIPs, on the other hand, are heterogeneous materials containing binding sites with a wide array of binding affinities and selectivities. Demonstrated is that the binding behavior of MIPs can be accurately modeled by the heterogeneous Langmuir-Freundlich (LF) isotherm. The applicability of the LF isotherm to MIPs was demonstrated using five representative MIPs from the literature, including both homogeneous and heterogeneous MIPs. Previously, such comparisons required the use of several different binding models and analyses, including the Langmuir model, the Freundlich model, and numerical approximation techniques. In contrast, the LF model enabled direct comparisons of the binding characteristics of MIPs that have very different underlying distributions and were measured under different conditions. The binding parameters can be calculated directly using the LF fitting coefficients that yield a measure of the total number of binding sites, mean binding affinity, and heterogeneity. Alternatively, solution of the Langmuir adsorption integral for the LF model enabled direct calculation of the corresponding affinity spectrum from the LF fitting coefficients from a simple algebraic expression, yielding a measure of the number of binding sites with respect to association constant Finally, the ability of the LF isotherm to model MIPs suggests that a unimodal heterogeneous distribution is an accurate approximation of the distribution found in homogeneous and heterogeneous MIPs.
A large bis-urea macrocycle was synthesized and assembled into columnar nanotubes containing a si... more A large bis-urea macrocycle was synthesized and assembled into columnar nanotubes containing a sizable cavity. This purely organic nanotube is held together primarily by hydrogen bonding and yet shows remarkable thermal stability up to 180 degrees C in the presence and absence of acetic acid guest. This enables the nanotube to be used as reusable organic zeolite.
... Convergent Functional Groups. 15. Synthetic and Structural Studies of Large and Rigid Molecul... more ... Convergent Functional Groups. 15. Synthetic and Structural Studies of Large and Rigid Molecular Clefts Ken D. Shimizu, Torin M. Dewey, and J. Rebek, Jr.' ... SOC. 1987, 109, 65496551. (e) Galln, A.; Andreu, D.; Echavarren, AM; Prados, P.; de Mendoza, J. J. Am. Chem. Soc. ...
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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