Synthesis p. 3363 - 3373 (2010)
Update date:2022-08-02
Topics:
Zerovnik, Darja
Groselj, Uros
Kralj, David
Malavasic, Crt
Bezensek, Jure
Dahmann, Georg
Stare, Katarina
Meden, Anton
Stanovnik, Branko
Svete, Jurij
Three synthetic methods for the preparation of 1,5-disubstituted 1,5,6,7-tetrahydro-4H-pyrazolo[4,3-c]pyridin-4-ones as heterocyclic histamine analogues were developed. The first method starts from easily available methyl 5-(2-aminoethyl)-1H-pyrazole-4-carboxylates, which were N-alkylated and the resulting secondary amines were cyclised in the presence of a base to give the title compounds in 17-92% yields (method A). Alternatively, the amines were first cyclised to the 5-unsubstituted pyrazolo[4,3-c]pyridin-4-ones. Subsequent N-benzylation afforded three of the title compounds in 36-49% yields (method B). The third method comprises a six-step transformation of methyl acrylate into 1-benzylpiperidine-2,4-dione. Treatment of the latter with N,N-dimethylformamide dimethylacetal (DMFDMA) followed by acid-catalysed cyclisation of the formed enaminone with methyl-, phenyl- and tert-butylhydrazine afforded the same three title compounds in 79-87% yields (method C). Georg Thieme Verlag Stuttgart New York.
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Doi:10.1021/acscatal.9b03458
(2020)Doi:10.1016/j.tet.2010.09.069
(2010)Doi:10.1021/jo00005a014
(1991)Doi:10.1021/ja982488y
(1998)Doi:10.1016/j.tet.2011.05.118
(2011)Doi:10.1016/j.ica.2011.01.079
(2011)