Triterpenes and Phenolic Compounds from Euphorbia deightonii with Antiviral Activity against Herpes Simplex Virus Type-2.

Two undescribed compounds, 3 β, 7 β -dihydroxy-24-methylenelanosta-8-ene-11-one ( 1 ) and neolignane deightonin ( 4 ) were isolated from the aerial parts of Euphorbia deightonii Croizat together with six known compounds, namely, kansenone ( 2 ), euphorbol-7-one ( 3 ), dehydrodiconiferyl diacetate ( 5 ), marylaurencinol D ( 6 ), scoparon ( 7 ), and 3,4,3'-tri- O -methylellagic acid ( 8 ). The structures of the isolated compounds were determined by HRESIMS, 1D ( 1 H, 13 C JMOD) and 2D NMR (HSQC, HMBC, 1 H- 1 H COSY, NOESY) spectroscopic analysis, and by comparison of the assignments with literature data. The anti-herpes simplex virus type-2 activity of the isolated compounds were investigated by qRT-PCR assay on Vero cells after determining cytotoxic concentration 50% (CC 50 ). Compounds 1 , 3 , 4 , and 7 exhibited inhibitory effects with respective IC 50 values of 7.05, 2.42, 11.73, and 0.032 µM. Scoparon ( 7 ) showed the strongest anti-HSV activity with a selectivity index of 10.93.