1.Discovery, Synthesis and Pre-Clinical Characterization of N-(3-chloro-4-fluorophenyl)-1H-pyrazolo[4,3-b]pyridin-3-amine (VU0418506), a novel positive allosteric modulator of the metabotropic glutamate receptor 4 (mGlu4).
Engers DW, Blobaum AL, Gogliotti RD, Cheung YY, Salovich JM, Garcia-Barrantes PM, Daniels JS, Morrison R, Jones CK, Soars MG, Zhuo X, Hurley J, Macor JE, Bronson JJ, Conn PJ, Lindsley CW, Niswender CM, Hopkins CR. ACS Chem Neurosci. 2016 Apr 13. [Epub ahead of print]
The efficacy of positive allosteric modulators (PAMs) of the metabotropic glutamate receptor 4 (mGlu4) in pre-clinical rodent models of Parkinson's disease has been established by a number of groups. Here, we report an advanced pre-clinically characterized mGlu4 PAM, N-(3-chloro-4-fluorophenyl)-1H-pyrazolo[4,3-b]pyridin-3-amine (VU0418506). We detail the discovery of VU0418506 starting from a common picolinamide core scaffold and evaluation of a number of amide bioisosteres leading to the novel pyrazolo[4,3-b]pyridine head group. VU0418506 has been characterized as a potent and selective mGlu4 PAM with suitable in vivo pharmacokinetic properties in three preclinical safety species.
2.High-performance liquid chromatographic enantioseparation of fluorinated cyclic ß3 -amino acid derivatives on polysaccharide-based chiral stationary phases. Comparison with nonfluorinated counterparts.
Lajkó G1,2, Orosz T1, Kiss L2, Forró E2, Fülöp F2, Péter A1, Ilisz I1. Biomed Chromatogr. 2016 Feb 13. doi: 10.1002/bmc.3702. [Epub ahead of print]
The stereoisomers of five fluorinated cyclic ß3 -amino acid derivatives and their nonfluorinated counterparts were separated on chiral stationary phases containing as chiral selectors cellulose tris-(3,5-dimethylphenyl carbamate), or cellulose tris-(3-chloro-4-methylphenyl carbamate), or cellulose tris-(4-methylbenzoate), or cellulose tris-(4-chloro-3-methylphenyl carbamate), or amylose tris-(3,5-dimethylphenyl carbamate) or amylose tris-(5-chloro-2-methylphenyl carbamate). The enantioseparations were carried out in normal-phase mode with n-hexane/alcohol/alkylamine mobile phases in the temperature range 5-40 °C. The effects of the mobile phase composition, the nature and concentration of the alcohol and alkylamine additives, the structures of the analytes and temperature on the separations were investigated. Thermodynamic parameters were calculated from plots of ln α versus 1/T. The Δ(ΔH°) values ranged between -5.0 and +1.6 kJ mol-1 , while Δ(ΔS°) varied between -12.
3.Fluorescence spectroscopy for monitoring reduction of natural organic matter and halogenated furanone precursors by biofiltration.
Peleato NM1, McKie M2, Taylor-Edmonds L2, Andrews SA2, Legge RL3, Andrews RC2. Chemosphere. 2016 Jun;153:155-61. doi: 10.1016/j.chemosphere.2016.03.018. Epub 2016 Mar 24.
The application of fluorescence spectroscopy to monitor natural organic matter (NOM) reduction as a function of biofiltration performance was investigated. This study was conducted at pilot-scale where a conventional media filter was compared to six biofilters employing varying enhancement strategies. Overall reductions of NOM were identified by measuring dissolved organic carbon (DOC), and UV absorbance at 254 nm, as well as characterization of organic sub-fractions by liquid chromatography-organic carbon detection (LC-OCD) and parallel factors analysis (PARAFAC) of fluorescence excitation-emission matrices (FEEM). The biofilter using granular activated carbon media, with exhausted absorptive capacity, was found to provide the highest removal of all identified PARAFAC components. A microbial or processed humic-like component was found to be most amenable to biodegradation by biofilters and removal by conventional treatment. One refractory humic-like component, detectable only by FEEM-PARAFAC, was not well removed by biofiltration or conventional treatment.
4.MPX-004 and MPX-007: New Pharmacological Tools to Study the Physiology of NMDA Receptors Containing the GluN2A Subunit.
Volkmann RA1, Fanger CM1, Anderson DR1, Sirivolu VR2, Paschetto K3, Gordon E3, Virginio C4, Gleyzes M5, Buisson B5, Steidl E5, Mierau SB6, Fagiolini M6, Menniti FS1. PLoS One. 2016 Feb 1;11(2):e0148129. doi: 10.1371/journal.pone.0148129. eCollection 2016.
GluN2A is the most abundant of the GluN2 NMDA receptor subunits in the mammalian CNS. Physiological and genetic evidence implicate GluN2A-containing receptors in susceptibility to autism, schizophrenia, childhood epilepsy and neurodevelopmental disorders such as Rett Syndrome. However, GluN2A-selective pharmacological probes to explore the therapeutic potential of targeting these receptors have been lacking. Here we disclose a novel series of pyrazine-containing GluN2A antagonists exemplified by MPX-004 (5-(((3-chloro-4-fluorophenyl)sulfonamido)methyl)-N-((2-methylthiazol-5-yl)methyl)pyrazine-2-carboxamide) and MPX-007 (5-(((3-fluoro-4-fluorophenyl)sulfonamido)methyl)-N-((2-methylthiazol-5-yl)methyl)methylpyrazine-2-carboxamide). MPX-004 and MPX-007 inhibit GluN2A-containing NMDA receptors expressed in HEK cells with IC50s of 79 nM and 27 nM, respectively. In contrast, at concentrations that completely inhibited GluN2A activity these compounds have no inhibitory effect on GluN2B or GluN2D receptor-mediated responses in similar HEK cell-based assays.