Two new limonoids from the stem barks of Chukrasia tabularis var. velutina

Two new phragmalin-type limonoid orthoesters, C-15 enolic acyl type and 13/14/18-cyclopropanyl type, named chukvelutilide H (1) and tabularin R (2), together with three known limonoid orthoesters (3-5), were isolated from the stem barks of Chukrasia tabularis var. velutina. The structures of these two new compounds were elucidated on their extensive HR-ESI-MS, 1D, and 2D spectroscopic analysis including HSQC, HMBC, and ROESY experiments.