Cyclopentane ring itself or as an element of bicyclic or polycyclic systems is not only ubiquitous in nature but also an increasingly recognized structural motif for biomedical research and drug discovery. In this context, the first part of the thesis describes our efforts towards synthetic analogs of a natural epoxy cyclopentenone isoprostane known to possess anti-inflammatory bioactivity. Employing reported strategies seven novel cyclopentenone isoprostanes were provided to our collaborators to examine their bioactivity. Additionally, preliminary studies demonstrated that the analog bearing an azide functionality could be labeled with an alkyne-containing cyanine (Cy5) and thus could serve as a valuable tool to further study the signaling pathway of related isoprostanes.
While numerous methodologies have been developed for the synthesis of this structural entity, the employment of known strategies to access relevant structural analogs can still be tedious and challenging. Acknowledging that, the second part of the thesis covers our investigations towards the use of vinylboron derivatives in radical-mediated [3 + 2] annulation reactions. The development of an efficient route giving access to 1,1-diborylethene in gram scale allowed us to extend the scope of this reaction allowing the synthesis of substituted cyclopentanes flanked with two boronic ester moieties. The established processes are operationally simple, convergent, atom economical, and mild. Thus, the synthesis of cyclopentanes presenting sensitive functional groups is enabled.
Additionally, the utility of the synthesized cyclopentane platforms was demonstrated by taking advantage of the presence of either the iodine atom, the boron atom(s), or both functionalities. These functionalization products include intriguing and applicable bicyclo[3.1.0]hexanes decorated with a boronic ester moiety, allylic gem-diboronates, and homoallyiodides among others, and are all easily accessible in one or two steps