- Synthesis, Nicotinic Acetylcholine Binding, and in Vitro and in Vivo Pharmacological Properties of 2′-Fluoro-(carbamoylpyridinyl)deschloroepibatidine Analogues
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In this study, we report the synthesis, nAChR in vitro and in vivo pharmacological properties of 2′-fluoro-(carbamoylpyridinyl)deschloroepibatidine analogues (5, 6a,b, and 7a,b), which are analogues of our lead structure epibatidine. All of the analogues had subnanomolar binding affinity for α4β2?-nAChRs, and all were potent antagonists of α4β2-nAChRs in an in vitro functional assay. Analogues 6a,b were also highly selective for α4β2- relative to α3β4- and α7-nAChRs. Surprisingly, all of the analogues were exceptionally potent antagonists of nicotine-induced antinociception in the mouse tail-flick test, relative to standard nAChR antagonists such as DHβE. 2′-Fluoro-(4-carbamoyl-3-pyridinyl)deschloroepitabidine (6a) displayed an attractive combination of properties, including subnanomolar binding affinity (Ki = 0.07 nM), submicromolar inhibition of α4β2-nAChRs in the functional assay (IC50 = 0.46 μM) with a high degree of selectivity for α4β2- relative to the α3β4/α7-nAChRs (54-/348-fold, respectively), potent inhibition of [3H]dopamine release mediated by α4β2?- and α6β2?-nAChRs in a synaptosomal preparation (IC50 = 21 and 32 nM, respectively), and an AD50 of 0.007 μg/kg as an antagonist of nicotine induced antinociception in the mouse tail-flick test which is 64raquo;250 times more potent than DHβE. These data suggest that compound 6a will be highly useful as a pharmacological tool for studying nAChRs and merits further development.
- Ondachi, Pauline W.,Castro, Ana H.,Luetje, Charles W.,Wageman, Charles R.,Marks, Michael J.,Damaj, M. Imad,Mascarella, S. Wayne,Navarro, Hernán A.,Carroll, F. Ivy
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- 2 - Amino - 4 - bromo pyridine synthesis method
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The invention relates to the field of medical intermediate synthesis, in particular to a synthetic method of 2-amino-4-bromopyridine, and provides a preparation method of 2-amino-4-bromopyridine. The preparation method comprises the following steps: (1) esterification reaction: esterifying 4-bromopyridinium chloride to obtain a 4-bromopyridine-2-ethyl formate crude product; (2) ammoniation reaction: ammonifying the 4-bromopyridine-2-ethyl formate crude product into 4-bromopyridine-2-formamide; (3) Hofmann degradation reaction: conducting Hofmann degradation on 4-bromopyridine-2-formamide to obtain 2-amino-4-bromopyridine, wherein the synthetic route is shown in the formula I. The synthetic method provided by the invention has the advantages that the raw material cost is low; the yield is high; the reactions and the operation are simple; the three waste treatment is convenient; industrialization can be realized easily.
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Paragraph 0059; 0063
(2018/04/26)
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