Paul Slattum - Academia.edu (original) (raw)
Papers by Paul Slattum
Journal of Medicinal Chemistry, Nov 16, 2010
We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo... more We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo-3H-quinazolin-6-yl)methyl-prop-2-ynylamino]-N-(3-pyridylmethyl)benzamide (CB38065, 1) is nicotinamide phosphoribosyltransferase (Nampt). With its cellular target known we sought to optimize the biochemical and cellular Nampt activity of 1 as well as its cytotoxicity. It was found that a 3-pyridylmethylamide substituent in the A region was critical to cellular Nampt activity and cytotoxicity, although other aromatic substitution did yield compounds with submicromolar enzymatic inhibition. Small unsaturated groups worked best in the D-region of the molecule, with 3,3-dimethylallyl providing optimal potency. The E region required a quinazolin-4-one or 1,2,3-benzotriazin-4-one group for activity, and many substituents were tolerated at C² of the quinazolin-4-one. The best compounds showed subnanomolar inhibition of Nampt and low nanomolar cytotoxicity in cellular assays.
® technology is designed to covalently attach marker molecules to nucleic acids in a simple one-s... more ® technology is designed to covalently attach marker molecules to nucleic acids in a simple one-step chemical reaction, allowing sensitive and precise detection of labeled samples. Label IT ® Reagents directly label RNA bases, and the labels and do not impact hybridization performance. Since Label IT ® Reagents allow the
The present invention concerns a method of forming POLYMERS IN THE PRESENCE nucleic acid using a ... more The present invention concerns a method of forming POLYMERS IN THE PRESENCE nucleic acid using a polymerization matrix. This invention relates to a process ALSO ALLOWS THE PRODUCE IN SYSTEMS polymerization heterophasic. Such methods may USED TO CHANNEL nucleic acids, to condense the nucleic acid to form polymers linking the nucleic acid to complex SUPRAMOLECULAR CONTAINING POLYMERS AND nucleic acid and to form a INTERPOLIELECTROLITA.
ACS Energy Letters, 2016
Perylene tetracarboxylic diimide (PTCDI) derivatives have been extensively investigated for one-d... more Perylene tetracarboxylic diimide (PTCDI) derivatives have been extensively investigated for one-dimensional (1D) self-assembly and their applications in optoelectronic devices. Our study on self-assembled PTCDI nanofiber materials revealed a persistent photoconductivity (PPC) effect, which is sustained conductivity after illumination is terminated. A comprehensive understanding of the PPC effect in PTCDI nanofibril materials will enable us to explore and enhance their optoelectronic applications. Here, we have investigated the PPC effect in the nanofibers assembled from 1-methylpiperidine-substituted perylene tetracarboxylic diimide (MP-PTCDI) with respect to the PPC relaxation at different temperatures, illumination power densities, molar amount, and morphology of the PTCDI film deposited on the interdigitated electrodes. The photocurrent relaxation was also performed on several other PTCDI nanofiber materials for comparative study. We conclude that the significant PPC effect in MP-PTCDI nanofibers can be attributed to the electrical potential fluctuations caused by the structure defects, which thus hinder the recombination of charge carriers. This study may provide new design rules for fabrication of molecular semiconductor materials with strong PPC in order to approach high efficiency of photovoltaics and photocatalysis.
The journal of physical chemistry letters, Jan 5, 2017
Thermoactivated electrical conductivity has been studied on nanofibers fabricated from the deriva... more Thermoactivated electrical conductivity has been studied on nanofibers fabricated from the derivatives of perylene tetracarboxylic diimide (PTCDI) both in the dark and under visible light illumination. The activation energy obtained for the nanofibers fabricated from donor-acceptor (D-A) PTCDIs are higher than that for symmetric n-dodecyl substituted PTCDI. Such difference originates from the strong dependence of thermoactivated charge hopping on material disorder, which herein is dominated by the D-A charge-transfer and dipole-dipole interactions between stacked molecules. When the nanofibers were heated above the first phase transition temperature (around 85 °C), the activation energy was significantly increased because of the thermally enhanced polaronic effect. Moreover, charge carrier density can be increased in the D-A nanofibers under visible light illumination. Consistent with the theoretical models in the literature, the increased charge carrier density did cause decrease i...
ACS applied materials & interfaces, May 18, 2016
Intrinsically low electrical conductivity of organic semiconductors hinders their further develop... more Intrinsically low electrical conductivity of organic semiconductors hinders their further development into practical electronic devices. Herein, we report on an efficient chemical self-doping to increase the conductivity through one-dimensional stacking arrangement of electron donor-acceptor (D-A) molecules. The D-A molecule employed was a 1-methylpiperidine-substituted perylene tetracarboxylic diimide (MP-PTCDI), of which the methylpiperidine moiety is a strong electron donor, and can form a charge transfer complex with PTCDI (acting as the acceptor), generating anionic radical of PTCDI as evidenced in molecular solutions. Upon self-assembling into nanoribbons through columnar π-π stacking, the intermolecular charge transfer interaction between methylpiperidine and PTCDI would be enhanced, and the electrons generated are delocalized along the π-π stacking of PTCDIs, leading to enhancement in conductivity. The conductive fiber materials thus produced can potentially be used as chemi...
![Research paper thumbnail of Analogues of 4-[(7-Bromo-2-methyl-4-oxo-3H-quinazolin-6-yl)methylprop-2-ynylamino]-N-(3-pyridylmethyl)benzamide (CB-30865) as Potent Inhibitors of Nicotinamide Phosphoribosyltransferase (Nampt)](https://attachments.academia-assets.com/111860723/thumbnails/1.jpg)
](Journal of Medicinal Chemistry, 2010
We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo... more We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo-3H-quinazolin-6-yl)methyl-prop-2-ynylamino]-N-(3-pyridylmethyl)benzamide (CB38065, 1) is nicotinamide phosphoribosyltransferase (Nampt). With its cellular target known we sought to optimize the biochemical and cellular Nampt activity of 1 as well as its cytotoxicity. It was found that a 3-pyridylmethylamide substituent in the A region was critical to cellular Nampt activity and cytotoxicity, although other aromatic substitution did yield compounds with submicromolar enzymatic inhibition. Small unsaturated groups worked best in the D-region of the molecule, with 3,3-dimethylallyl providing optimal potency. The E region required a quinazolin-4-one or 1,2,3-benzotriazin-4-one group for activity, and many substituents were tolerated at C 2 of the quinazolin-4-one. The best compounds showed subnanomolar inhibition of Nampt and low nanomolar cytotoxicity in cellular assays.
Journal of Medicinal Chemistry, Nov 16, 2010
We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo... more We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo-3H-quinazolin-6-yl)methyl-prop-2-ynylamino]-N-(3-pyridylmethyl)benzamide (CB38065, 1) is nicotinamide phosphoribosyltransferase (Nampt). With its cellular target known we sought to optimize the biochemical and cellular Nampt activity of 1 as well as its cytotoxicity. It was found that a 3-pyridylmethylamide substituent in the A region was critical to cellular Nampt activity and cytotoxicity, although other aromatic substitution did yield compounds with submicromolar enzymatic inhibition. Small unsaturated groups worked best in the D-region of the molecule, with 3,3-dimethylallyl providing optimal potency. The E region required a quinazolin-4-one or 1,2,3-benzotriazin-4-one group for activity, and many substituents were tolerated at C² of the quinazolin-4-one. The best compounds showed subnanomolar inhibition of Nampt and low nanomolar cytotoxicity in cellular assays.
® technology is designed to covalently attach marker molecules to nucleic acids in a simple one-s... more ® technology is designed to covalently attach marker molecules to nucleic acids in a simple one-step chemical reaction, allowing sensitive and precise detection of labeled samples. Label IT ® Reagents directly label RNA bases, and the labels and do not impact hybridization performance. Since Label IT ® Reagents allow the
The present invention concerns a method of forming POLYMERS IN THE PRESENCE nucleic acid using a ... more The present invention concerns a method of forming POLYMERS IN THE PRESENCE nucleic acid using a polymerization matrix. This invention relates to a process ALSO ALLOWS THE PRODUCE IN SYSTEMS polymerization heterophasic. Such methods may USED TO CHANNEL nucleic acids, to condense the nucleic acid to form polymers linking the nucleic acid to complex SUPRAMOLECULAR CONTAINING POLYMERS AND nucleic acid and to form a INTERPOLIELECTROLITA.
ACS Energy Letters, 2016
Perylene tetracarboxylic diimide (PTCDI) derivatives have been extensively investigated for one-d... more Perylene tetracarboxylic diimide (PTCDI) derivatives have been extensively investigated for one-dimensional (1D) self-assembly and their applications in optoelectronic devices. Our study on self-assembled PTCDI nanofiber materials revealed a persistent photoconductivity (PPC) effect, which is sustained conductivity after illumination is terminated. A comprehensive understanding of the PPC effect in PTCDI nanofibril materials will enable us to explore and enhance their optoelectronic applications. Here, we have investigated the PPC effect in the nanofibers assembled from 1-methylpiperidine-substituted perylene tetracarboxylic diimide (MP-PTCDI) with respect to the PPC relaxation at different temperatures, illumination power densities, molar amount, and morphology of the PTCDI film deposited on the interdigitated electrodes. The photocurrent relaxation was also performed on several other PTCDI nanofiber materials for comparative study. We conclude that the significant PPC effect in MP-PTCDI nanofibers can be attributed to the electrical potential fluctuations caused by the structure defects, which thus hinder the recombination of charge carriers. This study may provide new design rules for fabrication of molecular semiconductor materials with strong PPC in order to approach high efficiency of photovoltaics and photocatalysis.
The journal of physical chemistry letters, Jan 5, 2017
Thermoactivated electrical conductivity has been studied on nanofibers fabricated from the deriva... more Thermoactivated electrical conductivity has been studied on nanofibers fabricated from the derivatives of perylene tetracarboxylic diimide (PTCDI) both in the dark and under visible light illumination. The activation energy obtained for the nanofibers fabricated from donor-acceptor (D-A) PTCDIs are higher than that for symmetric n-dodecyl substituted PTCDI. Such difference originates from the strong dependence of thermoactivated charge hopping on material disorder, which herein is dominated by the D-A charge-transfer and dipole-dipole interactions between stacked molecules. When the nanofibers were heated above the first phase transition temperature (around 85 °C), the activation energy was significantly increased because of the thermally enhanced polaronic effect. Moreover, charge carrier density can be increased in the D-A nanofibers under visible light illumination. Consistent with the theoretical models in the literature, the increased charge carrier density did cause decrease i...
ACS applied materials & interfaces, May 18, 2016
Intrinsically low electrical conductivity of organic semiconductors hinders their further develop... more Intrinsically low electrical conductivity of organic semiconductors hinders their further development into practical electronic devices. Herein, we report on an efficient chemical self-doping to increase the conductivity through one-dimensional stacking arrangement of electron donor-acceptor (D-A) molecules. The D-A molecule employed was a 1-methylpiperidine-substituted perylene tetracarboxylic diimide (MP-PTCDI), of which the methylpiperidine moiety is a strong electron donor, and can form a charge transfer complex with PTCDI (acting as the acceptor), generating anionic radical of PTCDI as evidenced in molecular solutions. Upon self-assembling into nanoribbons through columnar π-π stacking, the intermolecular charge transfer interaction between methylpiperidine and PTCDI would be enhanced, and the electrons generated are delocalized along the π-π stacking of PTCDIs, leading to enhancement in conductivity. The conductive fiber materials thus produced can potentially be used as chemi...
Journal of Medicinal Chemistry, 2010
We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo... more We have shown previously that the target of the potent cytotoxic agent 4-[(7-bromo-2-methyl-4-oxo-3H-quinazolin-6-yl)methyl-prop-2-ynylamino]-N-(3-pyridylmethyl)benzamide (CB38065, 1) is nicotinamide phosphoribosyltransferase (Nampt). With its cellular target known we sought to optimize the biochemical and cellular Nampt activity of 1 as well as its cytotoxicity. It was found that a 3-pyridylmethylamide substituent in the A region was critical to cellular Nampt activity and cytotoxicity, although other aromatic substitution did yield compounds with submicromolar enzymatic inhibition. Small unsaturated groups worked best in the D-region of the molecule, with 3,3-dimethylallyl providing optimal potency. The E region required a quinazolin-4-one or 1,2,3-benzotriazin-4-one group for activity, and many substituents were tolerated at C 2 of the quinazolin-4-one. The best compounds showed subnanomolar inhibition of Nampt and low nanomolar cytotoxicity in cellular assays.