Correction: Nukulkit et al. Eight Indole Alkaloids from the Roots of <i>Maerua siamensis</i> and Their Nitric Oxide Inhibitory Effects. <i>Molecules</i> 2022, <i>27</i>, 7558

After a proofreading check, some experimental data were inconsistent with the supplementary information in the original publication [...

Eight Indole Alkaloids from the Roots of Maerua siamensis and Their Nitric Oxide Inhibitory Effects

Maerua siamensis (Capparaceae) roots are used for treating pain and inflammation in traditional Thai medicine. Eight new indole alkaloids, named maeruanitriles A and B, maeroximes A&ndash;C, and maeruabisindoles A&ndash;C, were isolated from them. Spectroscopic methods and computational analysis were applied to determine the structure of the isolated compounds. Maeroximes A&ndash;C possesses an unusual O-methyloxime moiety. The bisindole alkaloid maeruabisindoles A and B possess a rare azete ring, whereas maeruabisindole C is the first indolo[3,2-b]carbazole derivative found in this plant family. Five compounds [maeruanitriles A and B, maeroxime C, maeruabisindoles B, and C] displayed anti-inflammatory activity by inhibiting nitric oxide (NO) production in the lipopolysaccharide-induced RAW 264.7 cells. Maeruabisindole B was the most active inhibitor of NO production, with an IC50 of 31.1 &plusmn; 1.8 &mu;M compared to indomethacin (IC50 = 150.0 &plusmn; 16.0 &mu;M) as the positive control

A new benzoquinone and a new stilbenoid from <i>Paphiopedilum exul</i> (Ridl.) Rolfe

One new alkyl benzoquinone, paphionone (1), one new trans-stilbenoid, (E)-6,5′-dihydroxy-2,3′-dimethoxystilbene (2), and eight known stilbenoids and flavonoids (3-10) were isolated from the leaves and roots of Paphiopedilum exul (Orchidaceae). Their chemical structures were determined based on IR, ECD, MS and NMR analyses. Cytotoxicity of all isolated compounds towards human hepatocellular carcinoma (HepG2) cell line was examined in vitro by MTT assay. The para-hydroxybenzyl substituted stilbene 10 was potently cytotoxic to the cancer cells, with an IC50 value of 4.80 ± 1.10 μM (selectivity index = 20.83). All compounds were non-toxic to normal human embryo fibroblast (OUMS-36) cell line.</p