R. Jason Herr - Academia.edu (original) (raw)
Papers by R. Jason Herr
The Journal of Organic Chemistry, 2009
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
The Journal of Organic Chemistry
Modern Drug Synthesis, 2010
Organic Process Research & Development, 2002
A process for the multigram preparation of 5-(2-methoxy-4nitrophenyl)oxazole, a key intermediate ... more A process for the multigram preparation of 5-(2-methoxy-4nitrophenyl)oxazole, a key intermediate for the preparation of the hepatitis C drug candidate VX-497 (merimepodib), has been achieved in good yield from a commercially available dye. Early studies focused on the preparation of the requisite aldehyde by the Beech reaction. A second approach utilized a palladium (0)-catalyzed formylation of an aryl diazonium species, which was followed by condensation of the aldehyde with tosylmethyl isocyanide (TosMIC) to provide the required oxazole. This twostep method has been carried out to provide multigram samples of this key intermediate in 75% overall yield and >95% purity from the commercially available Fast Red B tetrafluoroborate salt.
Bioorganic & Medicinal Chemistry, 2020
The evolution of gamma-secretase modulators (GSMs) through the introduction of novel heterocycles... more The evolution of gamma-secretase modulators (GSMs) through the introduction of novel heterocycles with the goal of aligning activity for reducing the levels of Aβ42 and properties consistent with a drug-like molecule are described. The insertion of a methoxypyridine motif within the tetracyclic scaffold provided compounds with improved activity for arresting Aβ42 production as well as improved properties, including solubility. In vivo pharmacokinetic analysis demonstrated that several compounds within the novel series were capable of crossing the BBB and accessing the therapeutic target. Treatment with methoxypyridine-derived compound 64 reduced Aβ42 levels in the plasma of J20 mice, in addition to reducing Aβ42 levels in the plasma and brain of Tg2576 mice.
Bioorganic & medicinal chemistry letters, Aug 6, 2016
The design and construction of a series of novel aminothiazole-derived γ-secretase modulators is ... more The design and construction of a series of novel aminothiazole-derived γ-secretase modulators is described. The incorporation of heterocyclic replacements of the terminal phenyl D-ring of lead compound 1 was conducted in order to align potency with favorable drug-like properties. γ-Secretase modulator 28 displayed good activity for in vitro inhibition of Aβ42, as well as substantial improvement in ADME and physicochemical properties, including aqueous solubility. Pharmacokinetic evaluation of compound 28 in mice revealed good brain penetration, as well as good clearance, half-life, and volume of distribution which collectively support the continued development of this class of compounds.
Bioorganic & Medicinal Chemistry Letters, 2015
IRAK4 plays a key role in TLR/IL-1 signaling. Previous efforts identified a series of aminopyrimi... more IRAK4 plays a key role in TLR/IL-1 signaling. Previous efforts identified a series of aminopyrimidine IRAK4 inhibitors that possess good potency, but modest kinase selectivity. Exploration of substituents at the C-2 and C-5 positions generated compounds that maintained IRAK4 potency and improved kinase selectivity. Additionally, it was found that the pyrimidine core could be replaced with a pyridine and still retain potency and kinase selectivity. The optimization efforts led to compound 26 which had an IRAK4 IC50 of 0.7nM, an IC50 of 55nM on THP-1 cells stimulated with LPS, a TLR4 agonist, and greater than 100-fold selectivity versus 96% of a panel of 306 kinases.
Bioorganic & medicinal chemistry letters, Jan 28, 2015
Interleukin receptor-associated kinase 4 (IRAK4) is a critical element of the Toll-like/interleuk... more Interleukin receptor-associated kinase 4 (IRAK4) is a critical element of the Toll-like/interleukin-1 receptor inflammation signaling pathway. A screening campaign identified a novel diaminopyrimidine hit that exhibits weak IRAK4 inhibitory activity and a ligand efficiency of 0.25. Hit-to-lead activities were conducted through independent SAR studies of each of the four pyrimidine substituents. Optimal activity was observed upon removal of the pyrimidine C-4 chloro substituent. The intact C-6 carboribose is required for IRAK4 inhibition. Numerous heteroaryls were tolerated at the C-5 position, with azabenzothiazoles conferring the best activities. Aminoheteroaryls were preferred at the C-2 position. These studies led to the discovery of inhibitors 35, 36, and 38 that exhibit nanomolar inhibition of IRAK4, improved ligand efficiencies, and modest kinase selectivities.
Bioorganic & Medicinal Chemistry Letters, 2014
A series of pyrrolo-benzo-1,4-diazine analogs have been synthesized and displayed potent Na v 1.7... more A series of pyrrolo-benzo-1,4-diazine analogs have been synthesized and displayed potent Na v 1.7 inhibitory activity and moderate selectivity over Na v 1.5. The syntheses, structure-activity relationships, and selected pharmacokinetic data of these analogs are described. Compound 41 displayed anti-nociceptive efficacy in the rat CFA pain model at 100 mpk oral dosing.
Bioorganic & Medicinal Chemistry Letters, 2014
The Journal of Organic Chemistry, 2009
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
The Journal of Organic Chemistry
Modern Drug Synthesis, 2010
Organic Process Research & Development, 2002
A process for the multigram preparation of 5-(2-methoxy-4nitrophenyl)oxazole, a key intermediate ... more A process for the multigram preparation of 5-(2-methoxy-4nitrophenyl)oxazole, a key intermediate for the preparation of the hepatitis C drug candidate VX-497 (merimepodib), has been achieved in good yield from a commercially available dye. Early studies focused on the preparation of the requisite aldehyde by the Beech reaction. A second approach utilized a palladium (0)-catalyzed formylation of an aryl diazonium species, which was followed by condensation of the aldehyde with tosylmethyl isocyanide (TosMIC) to provide the required oxazole. This twostep method has been carried out to provide multigram samples of this key intermediate in 75% overall yield and >95% purity from the commercially available Fast Red B tetrafluoroborate salt.
Bioorganic & Medicinal Chemistry, 2020
The evolution of gamma-secretase modulators (GSMs) through the introduction of novel heterocycles... more The evolution of gamma-secretase modulators (GSMs) through the introduction of novel heterocycles with the goal of aligning activity for reducing the levels of Aβ42 and properties consistent with a drug-like molecule are described. The insertion of a methoxypyridine motif within the tetracyclic scaffold provided compounds with improved activity for arresting Aβ42 production as well as improved properties, including solubility. In vivo pharmacokinetic analysis demonstrated that several compounds within the novel series were capable of crossing the BBB and accessing the therapeutic target. Treatment with methoxypyridine-derived compound 64 reduced Aβ42 levels in the plasma of J20 mice, in addition to reducing Aβ42 levels in the plasma and brain of Tg2576 mice.
Bioorganic & medicinal chemistry letters, Aug 6, 2016
The design and construction of a series of novel aminothiazole-derived γ-secretase modulators is ... more The design and construction of a series of novel aminothiazole-derived γ-secretase modulators is described. The incorporation of heterocyclic replacements of the terminal phenyl D-ring of lead compound 1 was conducted in order to align potency with favorable drug-like properties. γ-Secretase modulator 28 displayed good activity for in vitro inhibition of Aβ42, as well as substantial improvement in ADME and physicochemical properties, including aqueous solubility. Pharmacokinetic evaluation of compound 28 in mice revealed good brain penetration, as well as good clearance, half-life, and volume of distribution which collectively support the continued development of this class of compounds.
Bioorganic & Medicinal Chemistry Letters, 2015
IRAK4 plays a key role in TLR/IL-1 signaling. Previous efforts identified a series of aminopyrimi... more IRAK4 plays a key role in TLR/IL-1 signaling. Previous efforts identified a series of aminopyrimidine IRAK4 inhibitors that possess good potency, but modest kinase selectivity. Exploration of substituents at the C-2 and C-5 positions generated compounds that maintained IRAK4 potency and improved kinase selectivity. Additionally, it was found that the pyrimidine core could be replaced with a pyridine and still retain potency and kinase selectivity. The optimization efforts led to compound 26 which had an IRAK4 IC50 of 0.7nM, an IC50 of 55nM on THP-1 cells stimulated with LPS, a TLR4 agonist, and greater than 100-fold selectivity versus 96% of a panel of 306 kinases.
Bioorganic & medicinal chemistry letters, Jan 28, 2015
Interleukin receptor-associated kinase 4 (IRAK4) is a critical element of the Toll-like/interleuk... more Interleukin receptor-associated kinase 4 (IRAK4) is a critical element of the Toll-like/interleukin-1 receptor inflammation signaling pathway. A screening campaign identified a novel diaminopyrimidine hit that exhibits weak IRAK4 inhibitory activity and a ligand efficiency of 0.25. Hit-to-lead activities were conducted through independent SAR studies of each of the four pyrimidine substituents. Optimal activity was observed upon removal of the pyrimidine C-4 chloro substituent. The intact C-6 carboribose is required for IRAK4 inhibition. Numerous heteroaryls were tolerated at the C-5 position, with azabenzothiazoles conferring the best activities. Aminoheteroaryls were preferred at the C-2 position. These studies led to the discovery of inhibitors 35, 36, and 38 that exhibit nanomolar inhibition of IRAK4, improved ligand efficiencies, and modest kinase selectivities.
Bioorganic & Medicinal Chemistry Letters, 2014
A series of pyrrolo-benzo-1,4-diazine analogs have been synthesized and displayed potent Na v 1.7... more A series of pyrrolo-benzo-1,4-diazine analogs have been synthesized and displayed potent Na v 1.7 inhibitory activity and moderate selectivity over Na v 1.5. The syntheses, structure-activity relationships, and selected pharmacokinetic data of these analogs are described. Compound 41 displayed anti-nociceptive efficacy in the rat CFA pain model at 100 mpk oral dosing.
Bioorganic & Medicinal Chemistry Letters, 2014