UPLC-ESI-MRM/MS for Absolute Quantification and MS/MS Structural Elucidation of Six Specialized Pyranonaphthoquinone Metabolites From Ventilago harmandiana

Pyranonaphthoquinones (PNQs) are important structural scaffolds found in numerous natural products. Research interest in these specialized metabolites lies in their natural occurrence and therapeutic activities. Nonetheless, research progress has thus far been hindered by the lack of analytical standards and analytical methods for both qualitative and quantitative analysis. We report here that various parts of Ventilago harmandiana are rich sources of PNQs. We developed an ultraperformance liquid chromatography-electrospray ionization multiple reaction monitoring/mass spectrometry method to quantitatively determine six PNQs from leaves, root, bark, wood, and heartwood. The addition of standards in combination with a stable isotope of salicylic acid-D-6 was used to overcome the matrix effect with average recovery of 82% +/- 1% (n = 15). The highest concentration of the total PNQs was found in the root (11,902 mu g/g dry weight), whereas the lowest concentration was found in the leaves (28 mu g/g dry weight). Except for the root, PNQ-332 was found to be the major compound in all parts of V. harmandiana, accounting for similar to 48% of the total PNQs quantified in this study. However, PNQ-318A was the most abundant PNQ in the root sample, accounting for 27% of the total PNQs. Finally, we provide novel MS/MS spectra of the PNQs at different collision induction energies: 10, 20, and 40 eV (POS and NEG). For structural elucidation purposes, we propose complete MS/MS fragmentation pathways of PNQs using MS/MS spectra at collision energies of 20 and 40 eV. The MS/MS spectra along with our discussion on structural elucidation of these PNQs should be very useful to the natural products community to further exploring PNQs in V. harmandiana and various other sources

Aristolactam-Type Alkaloids from Orophea enterocarpa and Their Cytotoxicities

A new aristolactam, named enterocarpam-III (10-amino-2,3,4,6-tetramethoxy phenanthrene-1-carboxylic acid lactam, 1) together with the known alkaloid stigmalactam (2), were isolated from Orophea enterocarpa. Their structures were elucidated on the basis of interpretation of their spectroscopic data. Compounds 1 and 2 exhibited significant cytotoxicities against human colon adenocarcinoma (HCT15) cell line with IC50 values of 1.68 and 1.32 μM, respectively

Aristolactam-Type Alkaloids from <em>Orophea enterocarpa</em> and Their Cytotoxicities

A new aristolactam, named enterocarpam-III (10-amino-2,3,4,6-tetramethoxy phenanthrene-1-carboxylic acid lactam, <strong>1</strong>) together with the known alkaloid stigmalactam (<strong>2</strong>), were isolated from <em>Orophea enterocarpa</em>. Their structures were elucidated on the basis of interpretation of their spectroscopic data. Compounds <strong>1</strong> and <strong>2</strong> exhibited significant cytotoxicities against human colon adenocarcinoma (HCT15) cell line with IC<sub>50</sub> values of 1.68 and 1.32 μM, respectively

Cytotoxic Aporphine Alkaloids from Leaves and Twigs of Pseuduvaria trimera (Craib)

From ethyl acetate-methanol extracts of leaves and twigs of Pseuduvaria trimera a new aporphine alkaloid; 8-hydroxy-1,4,5-trimethoxy-7-oxoaporphine or 8-hydroxyartabonatine C (1) was isolated, together with the known 1,2,3-trimethoxy-4,5-dioxo-6a,7-dehydroaporphine (ouregidione, 2). Their structures were elucidated by a combination of spectral methods; mainly 2D NMR; IR and MS. Compounds 1 and 2 exhibited cytotoxic activity with IC50 values of 26.36 ± 5.18 μM and 12.88 ± 2.49 μM, respectively, for human hepatocellular carcinoma HepG2 cells, and 64.75 ± 4.45 and 67.06 ± 3.5 μM, respectively, for human breast cancer MDA-MB231 cells. Both compounds displayed anti-cancer activity but less than that of doxorubicin; a conventional chemotherapeutic drug, the IC50 levels of which were 2.21 ± 1.72 and 1.83 ± 0.09 μM for HepG2 and MDA-MB231 cells, respectively

Two new labdane-type diterpenoids cinnamate from <i>Croton decalvatus</i> Esser

<p>Two new labdane diterpene derivatives, crotondecalvatin A (<b>1</b>) and crotondecalvatin B (<b>2</b>) were obtained from the leaves and twigs of <i>Croton decalvatus</i>. The structures of compounds were established on the basis of extensive spectroscopic data.</p

Study on the absolute configuration and biological activity of rotenoids from the leaves and twigs of Millettia pyrrhocarpa Mattapha, Forest & Hawkins, sp. Nov

Abstract Background M. pyrrhocarpa is a new plant in the Fabaceae: Faboideae family that is found in Thailand. A literature search revealed that the Milletia genus is rich in bioactive compounds possessing a wide range of biological activities. In this study, we aimed to isolate novel bioactive compounds and to study their bioactivities. Methods The hexane, ethyl acetate, and methanol extracts from the leaves and twigs of M. pyrrhocarpa were isolated and purified using chromatography techniques. These extracts and pure compounds were tested in vitro for their inhibitory activities against nine strains of bacteria, as well as their anti-HIV-1 virus activity and cytotoxicity against eight cancer cell lines. Results Three rotenoids, named 6aS, 12aS, 12S-elliptinol (1), 6aS, 12aS, 12S-munduserol (2), dehydromunduserone (3), and crude extracts were evaluated for antibacterial, anti-HIV, and cytotoxic activities. It was found that compounds 1–3 inhibited the growth of nine strains of bacteria, and the best MIC/MBC values were obtained at 3/ > 3 mg/mL. The hexane extract showed anti-HIV-1 RT with the highest %inhibition at 81.27 at 200 mg/mL, while 6aS, 12aS, 12S-elliptinol (1) reduced syncytium formation in 1A2 cells with a maximum EC50 value of 4.48 μM. Furthermore, 6aS, 12aS, 12S-elliptinol (1) showed cytotoxicity against A549 and Hep G2 cells with maximum ED50 values of 2.27 and 3.94 μg/mL. Conclusion This study led to the isolation of constituents with potential for medicinal application, providing compounds (1–3) as lead compounds against nine strains of bacteria. The hexane extract showed the highest %inhibition of HIV-1 virus, Compound 1 showed the best EC50 in reducing syncytium formation in 1A2 cells, and it also showed the best ED50 against human lung adenocarcinoma (A549) and human hepatocellular carcinoma (Hep G2). The isolated compounds from M. pyrrhocarpa offered significant potential for future medicinal application studies