Liu, Zhibo et al. published their research in Organic Letters in 2012 | CAS: 33439-27-9

1-Tosylpiperidin-4-one (cas: 33439-27-9) belongs to piperidine derivatives. The piperidine structural motif is present in numerous natural alkaloids. These include piperine, which gives black pepper its spicy taste. Piperidine derivatives bearing a masked aldehyde function in the ε-position are easily transformed into quinolizidine compounds through intramolecular reductive amination.Electric Literature of C12H15NO3S

Expedient Approach to Novel N-Unprotected Bicyclic Azapyrimidine and Pyridine Structures was written by Liu, Zhibo;Qin, Ling;Zard, Samir Z.. And the article was included in Organic Letters in 2012.Electric Literature of C12H15NO3S This article mentions the following:

A direct route to novel bicyclic N-unprotected azapyrimidine structures including fused five-, six-, and seven-membered rings is described involving radical addition and cyclization of xanthates; this approach could be partially extended to pyridines. In the experiment, the researchers used many compounds, for example, 1-Tosylpiperidin-4-one (cas: 33439-27-9Electric Literature of C12H15NO3S).

1-Tosylpiperidin-4-one (cas: 33439-27-9) belongs to piperidine derivatives. The piperidine structural motif is present in numerous natural alkaloids. These include piperine, which gives black pepper its spicy taste. Piperidine derivatives bearing a masked aldehyde function in the ε-position are easily transformed into quinolizidine compounds through intramolecular reductive amination.Electric Literature of C12H15NO3S

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem