12-Nor-rotenoids and other cytotoxic constituents of Pachyrhizus erosus seeds.

Five previously undescribed compounds, including three 12-nor-rotenoids, were isolated from Pachyrhizus erosus seeds. A brief survey on the dealkylation of selected rotenoids with BBr3 was undertaken. Spectroscopic data of these previously undescribed compounds and reaction products are reported. The proposal of absolute configurations at stereocenters in the isolates and reaction products was based on NMR and ECD data. Most of the isolates and reaction products were evaluated for their growth inhibitory activities against four cancer cell lines and a Vero cell line. Many compounds exhibited strong to moderate activities with IC50 values ranging from 0.06 to 20.9 µM, and their structure-activity relationships were evaluated.

Furostanol glycosides, stilbenoids and nucleosides from the roots of Smilax perfoliata, and evaluation of their cytotoxic and anticholinesterase activities.

Three undescribed compounds including two furosteroid glycosides (perfoloside and 22-O-methylperfoloside) and one stilbenedimer (perfolostilbene) together with 21 known compounds were isolated from the roots of Smilax perfoliata. The structural elucidation was established by extensive uses of HRMS, 1D and 2D spectroscopic techniques. The assignment of the stereocenters in perfolostilbene was based on NOESY data and ECD calculation. Among the isolates, two compounds showed marginal cytotoxic activity against KB and Hela cell lines while seven stilbenoids showed strong to weak antiacetylcholinesterase and antibutyrylcholinesterase activities with IC50 ranging between 2-197 µM.

Neolignans from Myristica fragrans seeds, revision of their absolute configurations, reduction products and biological activities.

Chromatographic purification of the CH2Cl2 extract of Myristica fragrans seeds provided 19 known compounds, four dihydrofuran neolignans, licarines A, B and maceneolignans A, B were among the isolates. Prior to hydrogenation, in order to obtain their di- and tetrahydrogenated products, the absolute configuration of these compounds was thoroughly investigated based on their optical rotations and ECD spectra. This report provides evidences concerning the disagreement between the use of an aromatic quadrant rule and time-dependent density function theory calculation for the prediction of the absolute configurations at C-7 and C-8 in these dihydrobenzofuran neolignans. The absolute configurations of licarines A, B and maceneolignans A, B were subsequently redefined. The antimicrobial and cytotoxic activities of the isolates and reduction products of licarines A, B and maceneolignans A, B were also investigated.

Siphonagarofurans A-J: Poly-O-acylated ß-dihydroagarofuran sesquiterpenoids from the fruits of Siphonodon celastrineus.

Ten poly-O-acylated ß-dihydroagarofuran sesquiterpenoids, siphonagarofurans A-J, were obtained from the fruits of Siphonodon celastrineus using chromatographic techniques. Their structures were elucidated by extensive use of 2-D NMR spectroscopic methods. The absolute configurations of siphonagarofurans A-J were assigned following analysis of calculated and experimental ECD spectra. The absolute configuration of siphonagarofuran A was also confirmed by X-ray crystallographic analysis. Selected compounds were evaluated for their cytotoxic activity against KB, Vero and Hela cell lines with siphonagarofuran J identified as the most active compound, with IC50 values ranging from 14 to 27 µM.