Correction: Structural modification of olibergin A, an isoflavonoid, from Dalbergia stipulacea Roxb. and its cytotoxicity.

[This corrects the article DOI: 10.1039/D2RA02865D.].

Structural modification of olibergin A, an isoflavonoid, from Dalbergia stipulacea Roxb. and its cytotoxicity.

Fifteen derivatives were synthesized from olibergin A, a major isoflavonoid isolated from the stems of Dalbergia stipulacea Roxb. All compounds were evaluated for cytotoxicity against HCT-116, HT-29, MCF-7 and vero cell lines using MTT assay. Cytotoxicity results showed 5-hydroxy-7,2',4',5'-tetramethoxyisoflavone (5) was the most active with IC50 values of 19.03 ± 0.70, 10.83 ± 1.65, 12.53 ± 0.70 and 13.53 ± 0.84 µM against HCT-116, HT-29, MCF-7 and vero cell lines, respectively. It should be noted that 5-hydroxy-7,2',4',5'-tetramethoxyisoflavone (5) showed two times less toxicity against vero cells than the cisplatin standard (IC50 = 6.55 ± 0.81 µM) while 5 and cisplatin exhibited nearly equal cytotoxicity against the MCF-7 cell line. 5,7,2',4',5'-Pentamethoxyisoflavanone (10) showed an IC50 value of 30.34 ± 1.15 µM against the HCT-116 cell line and exhibited weak cytotoxicity against normal cells, the vero cell line. In addition, 5,7,4'-trihydroxy-2',5'-dimethoxyisoflavan oxime (13) demonstrated cytotoxicity against HT-29 cells with an IC50 value of 31.41 ± 1.38 µM and displayed weak activity toward the vero cell line. The information revealed that these compounds were suitable for development to anticancer agents against HCT-116, HT-29 and MCF-7 cell lines.

Dalpulapans A-E from the roots of Dalbergia stipulacea.

Five new compounds, dalpulapans A-E (1-5), were isolated from the hexane extract of the roots of Dalbergia stipulacea Roxb. Five new compounds, dalpulapans A-E (1-5), were isolated from the hexane extract of the roots of Dalbergia stipulacea Roxb. An evaluation of cytotoxic activity against HeLa, A549 and normal cell lines using MTT assay was performed. The results showed that R,R-velucarpin A (6) was the most active against HeLa cells with an IC50 value of 10.9 ± 0.42 µM, while fortunately this compound exhibited weak cytotoxicity against normal cells (29.20 ± 1.16 µM). Structures of all isolates were identified from their 1D and 2D NMR spectroscopic data and MS analysis. Experimental and calculated ECD spectra were studied to define the absolute configurations.