Evaluation of Spirooxindole-3,3'-pyrrolines-incorporating Isoquinoline Motif as Antitumor, Anti-inflammatory, Antibacterial, Antifungal, and Antioxidant Agents.

Background: A series of novel 2-(isoquinolin-1-yl)-spiro[oxindole-3,3'-pyrrolines] were synthesized by a one-pot three-component reaction involving dimethyl acetylenedicarboxylate, 3-phenylimidazo[5,1-a]isoquinoline and N-alkylisatins in chloroform at ∼60°C for 24 h.

Aims: This study aimed at the synthesis of novel spirooxindole-3,3'-pyrrolines derivatives and in vitro evaluation of cytotoxicity affinities in cross-correlations with their anti-inflammation and radical scavenging capacities.

Objectives: The objective of this study was to use a one-pot, three-component reaction to synthesize a novel set of spirooxindole-3,3'-pyrrolines derivatives.

Methods: A novel set of spirooxindole-3,3'-pyrrolines (8a-i) was synthesized by a one-pot three-component reaction involving dimethyl acetylenedicarboxylate, 3-phenylimidazo[5,1- a]isoquinoline and N-alkylisatins in chloroform at ∼60°C for 24 h. These new compounds were characterized by ¹HNMR, ¹³C-NMR, and HRMS spectral data and screened for their antitumor, anti-inflammatory, antibacterial, antifungal, and antioxidant activities.

Results: The new synthetic spirooxindole-3,3'-pyrrolines (8a-i)-tested compounds displayed significant anti-inflammatory properties and were noncytotoxic on PDL fibroblasts. However, they lacked antioxidative-DPPH radical scavenging capabilities. Notably, Doxorubicin and cisplatin demonstrated antiproliferative effects on various cancer monolayers. Moreover, compounds 8b, 8d, 8f, 8h, and 8i exhibited pronounced viability reduction properties in colorectal and pancreatic cancer monolayers, as well as across skin, lung, prostate, and cervical adenocarcinomas, with higher cytotoxicity in mammary cancer cells MCF7 and T47D. None of the tested compounds had significant antibacterial activity against S. aureus or E. coli. However, compounds 8c, 8d, and 8f exhibited notable antifungal properties, indicating potential for further investigation.

Conclusion: Eight new synthetic spiro[indoline-3,3-pyrroles] were prepared, characterized, and evaluated for their anti-inflammatory and cytotoxic properties. The compounds showed significant anti-inflammatory effects and promising cytotoxicity against various cancer monolayers, especially in colorectal and pancreatic cancers. Some compounds also exhibited antifungal properties. However, they did not exhibit significant antibacterial activity.