2‐aminothiophenes from triacetonamine: A convenient way to novel sterically hindered piperidine derivatives

Abstract

Bicyclic 2‐aminothiophenes 2, which are available by the Gewald reaction of 2,2,6,6‐tetramethyl‐4‐piperidone (triacetonamine, 1), were employed in cyclizations to give new tricyclic thienopyridine and thienopyrimidine derivatives, without protection of the piperidine nitrogen, whereas methylation of 2 occurred exclusively at the piperidine nitrogen. Acylation of 2 in the presence of a tertiary amine yielded N‐thienyl imides, due to the high NH acidity of the intermediate N‐thienyl amides. Similarly, benzylation of an N‐thienyl amide proceeded readily in sodium ethoxide solution. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:529–536, 1998

Thienopyridines: synthesis, properties, and biological activity

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Development of Thiophene Compounds as Potent Chemotherapies for the Treatment of Cutaneous Leishmaniasis Caused by Leishmania major

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