Substituted piperidine challenge

Piperidine ring systems are key structural elements in a vast array of natural products, as well as in a large class of biologically active compounds. They are often embedded within scaffolds recognized as privileged structures by medicinal chemists. The biological importance of this ring system places high value on short and versatile synthetic routes to substituted piperidines, and therefore makes rapid structural elucidation of these compounds crucial. Typically, these elucidations require acquiring a range of standard NMR experiments, such as COSY, HSQC, and NOESY, which makes the process quite time-consuming. In this challenge, we will attempt to distinguish cis/trans isomers of two 3,4-disubstituted piperidines from their heteronuclear (¹H-¹³C) single quantum coherence (HSQC) NMR spectra.