Anti-inflammatory iridoids from the stems of Cistanche deserticola cultured in Tarim Desert

In order to determine the chemical constituents of Cistanche deserticola cultured in Tarim desert,a systematically phytochemical investigation was carried out.The constituents were isolated by silica gel,Sephadex LH-20,MCI gel,ODS column chromatography,and semi-preparative HPLC.Their structures were determined on the basis of MS and NMR spectroscopic analyses,by chemical methods,and/or comparison with literature data.The anti-inflammatory activities of the isolates were evaluated for their inhibitory effects on the lipopolysaccharide（LPS）-induced nitric oxide（NO）production in BV-2 mouse microglial cells.Nine iridoids were isolated and identified as cistadesertoside A（1）,cistanin（2）,cistachlorin（3）,6-deoxycatalpol（4）,gluroside（5）,kankanoside A（6）,ajugol（7）,bartsioside（8）,and 8-epi-loganic acid（9）.Compound 9 exhibited potent inhibition on the NO production with an IC50 value being 5.2 μmol·L-1,comparable to the positive control quercetin(4.3 μmol·L-1).Compound 1 was a new iridoid,and compounds 5,6,and 8 were isolated from this species for the first time.