Triterpenes From Lagerstroemia indica L. Bark With Anti-ZIKV Activity

Two previously undescribed triterpenes, 2S,3R,23-trihydroxy-1-oxo-olean-12-en-28-oic acid (1) and 2S,3R-dihydroxy-1-oxo-olean-12-en-28-oic acid (2), along with 19 known triterpenes (3-21), were isolated from the bark of Lagerstroemia indica L. Their structures were determined by comprehensive spectroscopic analysis, including NMR, HR-ESI-MS, UV, and IR measurements. The absolute configurations were established through ECD calculations. Compound 4 demonstrated potent anti-ZIKV activity with an EC₅₀ value of 6.05 ± 0.51 µM. Notably, Compound 4 was shown to inhibit ZIKV envelope (E) protein expression and viral replication in a dose-dependent manner.