RESUMEN
A new nickel catalyzed cross-electrophile coupling for accessing γ-lactams (isoindolinones) as well as γ-lactones (isobenzofuranones) via carbonylation with CO2 is documented. The protocol exploits the synergistic role of redox-active Ni(II) complexes and AlCl3 as a CO2 activator/oxygen scavenger, leading to the formation of a wide range of cyclic amides and esters (28 examples) in good to high yields (up to 87 %). A dedicated computational investigation revealed the multiple roles played by AlCl3. In particular, the simultaneous transient protection of the pendant amino group of the starting reagents and the formation of the electrophilically activated CO2-AlCl3 adduct are shown to concur in paving the way for an energetically favorable mechanistic pathway.
RESUMEN
The study of natural products as potential drug leads has gained tremendous research interest. Quercetin is one of those natural products. It belongs to the family of flavonoids and, more specifically, flavonols. This review summarizes the beneficial pharmaceutical effects of quercetin, such as its anti-cancer, anti-inflammatory, and antimicrobial properties, which are some of the quercetin effects described in this review. Nevertheless, quercetin shows poor bioavailability and low solubility. For this reason, its encapsulation in macromolecules increases its bioavailability and therefore pharmaceutical efficiency. In this review, a brief description of the different forms of encapsulation of quercetin are described, and new ones are proposed. The beneficial effects of applying new pharmaceutical forms of nanotechnology are outlined.