Discovery of glucosyloxybenzyl 2-hydroxy-2-isobutylsuccinates with anti-inflammatory activities from Pleione grandiflora

Abstract

Six new glucosyloxybenzyl 2-hydroxy-2-isobutylsuccinates, pleionesides A-F (1-6), along with two known compounds (7, 8) were obtained from the pseudobulbs of Pleione grandiflora (Rolfe) Rolfe. The structures and absolute configurations of new compounds were established by HRESIMS and NMR data, along with acidic hydrolysis and alkaline hydrolysis experiments. Compounds 1-6 were tested for their anti-inflammatory activities on LPS-induced BV2 microglial cells. Amoung them, 2, 4 and 5 showed moderate activities with IC₅₀ values of 73.4, 32.8 and 57.1 μM, respectively, compared with the positive control quercetin with an IC₅₀ value of 28.3 μM.

Keywords: Glucosyloxybenzyl 2-hydroxy-2-isobutylsuccinates; Pleione grandiflora; Pseudobulbs.