Novel Approach to Isoindolo[2,1-a]quinolines

Synthesis of dihydroisoindolo[2,1-a]quinolin-11-ones, their in silico ADMET properties and in vitro antitumor activities

We evaluated the antitumoral activity of diverse series of 5-aryl-dihydroisoindolo[2,1-a]quinolin-11-ones, AIIQ (Aryl IsoIndolo-Quinoline, 4a-m), and 5-vinyl dihydroisoindolo[2,1-a]quinolin-11-ones, VIIQ (Vinyl IsoIndolo-Quinoline, 6a-l), obtained using three component imino Diels-Alder (DA) reaction of anilines, o-phthalaldehyde and dienophiles. The first series was obtained in previous work employing isoeugenol and anethole as dienophiles, whereas the vinyl series was synthesized in high yields (75-90%) using isoprene as a dienophile. The cytotoxic activity of both AIIQ and VIIQ series was evaluated against four cancer lines, identifying a new lead compound 4h from the AIIQ series, active against MCF-7 (310 nM), SKBR3 (1434 nM), PC3 (210 nM) and HeLa (79 nM) cells with high selectivity. In addition, in silico ADMET properties for the two series were assessed and discussed.

Advancements in the synthesis of fused tetracyclic quinoline derivatives

Fused tetracyclic systems containing a quinoline nucleus represent an important class of heterocyclic bioactive natural products and pharmaceuticals because of their significant and wide-spectrum biological properties. Several of these compounds have been obtained with diverse pharmacological and biological activities, such as antiplasmodial, antifungal, antibacterial, potent antiparasitic, antiproliferative, anti-tumor and anti-inflammatory activities. This information will be beneficial for medicinal chemists in the field of drug discovery to design and synthesize new fused tetracyclic quinolines as potent therapeutical agents. This review article provides a comprehensive report regarding the methods developed for the synthesis of fused tetracyclic quinolines reported so far (till October 2019). The article includes synthesis by one-pot domino reaction, microwave synthesis using a catalyst, using ionic liquids, photocatalytic synthesis (UV radiation), Pfitzinger reaction, I2-catalyzed cyclization reaction, Wittig reaction, cascade reaction, imino Diels-Alder reaction, Friedel-Crafts reaction, CDC reaction, solvent-free reactions and using small chiral organic molecules as catalysts. To the best of our knowledge, this is the first review focused on the synthesis of fused tetracyclic quinolines along with mechanistic aspects.

Organocatalytic C(sp3)-H Functionalization via Carbocation-Initiated Cascade [1,5]-Hydride Transfer/Cyclization: Synthesis of Dihydrodibenzo[b,e]azepines

Carbocation-initiated cascade [1,5]-hydride transfer/cyclization and dimerization reactions were developed to synthesize dihydrodibenzo[b,e]azepine and octahydrodipyrroloquinoline derivatives in high yields. These redox-neutral C(sp³)-H functionalization-involving cascade reactions feature transition-metal-free, high atom- and step-economy, and environmental friendliness with water as the sole byproduct.