Synthesis of the Corrected Structure Assigned to Clonorosin B, an Alkaloid Obtained from the Soil-derived Fungus Clonostachys rosea YRS-06.

ABSTRACT

The revised structure, 2, assigned to the title natural product has been prepared by chemical synthesis using a reaction sequence involving six simple steps starting from 2,3-dimethoxybenzaldehyde and proceeding via intermediates 8, 12, and 14. A comparison of the NMR data acquired on synthetically derived compound 2 with those reported for the natural product reveals an excellent match. Preliminary biological screening of compound 2 along with analogues/precursors 7, 9, 10, 11, 13, 14, and 15 revealed that none exhibited antibacterial, antifungal or cytotoxic effects.