6344-79-2Relevant academic research and scientific papers
Synthesis of regioisomeric pyrido[c]azocanones from azaindanone derivatives
Penning, Miriam,Christoffers, Jens
, p. 2140 - 2149 (2014/04/17)
A ring enlargement reaction with methylamine gave new pyrido[2,3-c]-, pyrido[3,4-c]- and pyrido[3,2-c]azocanone derivatives from cyclic β-oxo esters with a cyclopentapyridine skeleton and a 1,4-diketone moiety. The starting materials for this ring transformation were either prepared from halogenopyridine carboxylates by Heck reaction and subsequent hydrogenation, or (halogenomethyl)pyridine carboxylates were submitted to SN reaction with diethyl malonate. Both routes were completed by Dieckmann condensation to build the cyclic β-oxo ester structure and alkylation with phenacylbromide to install the 1,4-diketone motif. Copyright
Preparation of some Thiopyranopyridine Derivatives
Clarke, Kenneth,Goulding, John,Scrowston, Richard M.
, p. 1501 - 1505 (2007/10/02)
In the first systematic study of thiopyranopyridines in which the sulphur atom is separated from the pyridine ring by one carbon atom, the four isomeric enol esters, ethyl 5-hydroxy-8H-thiopyranopyridine-6-carboxylate (4b), ethyl 8-hydroxy-5H-thiopyranopyridine-7-carboxylate (5b), and ethyl 4-hydroxy-1H-thiopyrano- and pyridine-3-carboxylate (6b) and (7b), have been synthesised.Improved methods for the preparation of their pyridine precursors are described.With phenylhydrazine, the enol esters (4b) - (7b) give condensed pyrazole derivatives (15) - (18), which have dipolar structures; with hot mineral acid they undergo decarboxylative hydrolysis, to give the corresponding oxothiopyranopyridines (4a) - (7a).
