Organocatalytic double arylation of 3-isothiocyanato oxindoles: Stereocontrolled synthesis of complex spirooxindoles

Design, synthesis, and apoptotic evaluation of spiro[indoline-3,3'-pyrazolo[1,2-a]indazole] derivatives via [3 + 2] N,N-cycloaddition

An efficient protocol for the synthesis of spiro[indoline-3,3'-pyrazolo[1,2-a]indazole] derivatives was developed via a [3 + 2] N,N-cycloaddition strategy, utilizing substituted 2-(2-oxoindolin-3-ylidene)malononitrile derivatives and 1,2-dihydro-3H-indazol-3-one under mild conditions, yielding excellent results (3a-3l). Furthermore, selected derivatives (3e and 3h-3l) were evaluated for cytotoxicity against various cancer cell lines, including MCF-7 (breast cancer), A549 (lung cancer), Colo-205 (colon cancer), and A2780 (ovarian cancer). The IC50 values ranged from 1.34 ± 0.21 μM (for 3l against MCF-7) to 8.53 ± 1.49 μM (for 3h against A2780). Notably, derivative 3l demonstrated the most potent apoptotic activity, exhibiting the lowest IC50 values across all four cancer cell lines. Additionally, molecular docking studies corroborated the observed biological activity, suggesting that these compounds may interact with relevant cellular targets, potentially accounting for their cytotoxic effects.

Synthesis of triazole-fused tetracyclic spirooxindole derivatives via metal-free Huisgen cycloaddition

We report an efficient, metal free method for synthesizing tetracyclic spirooxindole derivatives from N-protected isatins and propargyl bromide via Huisgen cycloaddition. This simple and practicle method provides access to spirooxindoles containing five-, six-, or seven-membered rings fused to a triazole ring.

Insight on novel oxindole conjugates adopting different anti-inflammatory investigations and quantitative evaluation

Background: A dual COX/5-LOX strategy was adopted to develop new oxindole derivatives with superior anti-inflammatory activity. Methods: Three series of oxindoles - esters 4a-p, 6a-l and imines 7a-o - were synthesized and evaluated for their anti-inflammatory and analgesic activities. Molecular docking and predicted pharmacokinetic parameters were done for the most active compounds. A new LC-MS/MS method was developed and validated for the quantification of 4h in rat plasma. Results: Compounds 4h, 6d, 6f, 6j and 7m revealed % edema inhibition up to 100.00%; also, 4l and 7j showed 100.00% writhing protection. Compound 4h showed dual inhibitory activity with IC50 = 0.0533 and 0.4195 μM for COX-2 and 5-LOX, respectively. Molecular docking rationalized the obtained biological activity. The pharmacokinetic parameters of 4h from rat plasma were obtained.

Advances of α-activated cyclic isothiocyanate for the enantioselective construction of spirocycles

The efficient and enantioselective synthesis of pharmaceutically important spirocycles has attracted the focus of organic and medicinal chemists. In this context, with the excellent reactivity of α-activated isothiocyanate as formal 1,3-dipoles in the (3 + 2) cyclization process, the cyclic isothiocyanates featuring important pharmacophores, such as oxindole, pyrazolone, and indanone moieties, have emerged as powerful precursors to access a variety of spirocycles with highly structural diversities. In addition, the facile transformations of these spirocycles have shown potential applications in drug design. This review will cover the recent advances of α-activated cyclic isothiocyanates in the enantioselective construction of spirocycles since 2015, and the applications of corresponding products in organic and medicinal chemistry.

Recent advances in organocatalytic asymmetric multicomponent cascade reactions for enantioselective synthesis of spirooxindoles

Catalytic asymmetric MCCRs for enantioselective synthesis of spirooxindoles by using chiral phosphoric acids, amines, bifunctional thiourea/squaramides and metal-based reagents as catalysts.

Stereoselective synthesis and applications of spirocyclic oxindoles

This review summaries recent synthetic developments towards spirocyclic oxindoles and applications as valuable medicinal and synthetic targets.

Double Spirocyclization of Arylidene-Δ2-Pyrrolin-4-Ones with 3-Isothiocyanato Oxindoles

Arylidene-Δ2-pyrrolin-4-ones undergo organocatalyzed double spirocyclization with 3-isothiocianato oxindoles in a domino 1,4/1,2-addition sequence. The products contain three contiguous stereocenters (ee up to 98%, dr up to 99:1, 12 examples). The absolute configuration of the major diastereomer was determined by single crystal X-ray analysis. Along with heterocyclic Michael acceptors based on oxazolone, isoxazolone, thiazolidinone, pyrazolone, and pyrimidinedione, the reported results display the applicability of unsaturated Δ2-pyrrolin-4-ones (pyrrolones) for the organocatalyzed construction of 3D-rich pyrrolone-containing heterocycles.