Discovery of two new tirucallane-type triterpenes anomers from Toona ciliata

Toona ciliata, a member of the Meliaceae family, is valued for its high-quality timber and medicinal potential in treating various ailments. In this study, two triterpene isomers were isolated and characterised as an inseparable mixture from its chloroform extract using chromatography and spectroscopic techniques. Despite rigorous/extensive attempts to separate these isomers, they co-crystallised in a consistent 67:33 ratio, as verified by X-ray crystallography. The structure was further confirmed by ESI-MS, HRMS,¹H NMR,¹³C NMR, DEPT 90, DEPT 135, COSY, NOESY, HSQC, and HMBC. Additionally, four more compounds were isolated successfully, out of that lutein and dyscusin C found for the first time from this plant.