Regioselective Synthesis of Spiro-Ganoderma Meroterpenoid Motifs via Lewis Acid-Catalyzed Divergent Cycloadditions:
Muralikrishna Katta1,2, Cun-Han Wei1,2, Yong-Xian Cheng1,2
1Guangdong Provincial Key Laboratory of Chinese Medicine Ingredients and Gut Microbiomics Institute for Inheritance-Based Innovation of Chinese Medicine, Marshall Laboratory of Biomedical Engineering, School of Pharmacy, Shenzhen University Medical School, Shenzhen University, Shenzhen 518060, China.
Abstract:
For the first time, a water-driven Lewis acid-catalyzed [5 + 2] cyclization between allylsilanes and aurones was developed, affording spiro-Ganoderma-meroterpenoid (SGM) motifs with high yields and stereoselectivity. This method enables efficient construction of spiro-tricyclic rings, introducing contiguous stereocenters without dry conditions or thermal/photoactivation. This approach revealed dual catalysts over the regio-control [3 + 2] spirocyclic ring creation by opposite functional group incorporation and halting at the interim stage, facilitating the synthesis of SGM scaffolds.
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