Alkaloid and benzopyran compounds of Melicope latifolia fruit exhibit anti-hepatitis C virus activities.

BACKGROUND: New agents for developing alternative or complementary medicine to treat the hepatitis C virus (HCV) are still needed due to high rates of HCV infection globally and the current limitations of available treatments. Treatment of HCV with a combination of direct acting antivirals have been shown to be approximately 90% effective but will be limited in the future due to the emergence of drug resistance and high cost. The leaves of Melicope latifolia have previously been reported to have anti-HCV activity and are a potential source of bioactive compounds for future novel drug development. This study aimed to evaluate the efficacy of the extract of M. latifolia fruit to treat HCV and to isolate its active compounds. METHOD: M. latifolia fruit was extracted using methanol and purified using vacuum liquid chromatography (VLC) and Radial Chromatography. The anti-HCV activity was analyzed using cell culture lines Huh7it-1 and JFH1 (genotype 2a). Time-of-addition and immunoblotting studies were performed to identify the mode of action of the isolated active compounds. The structures of the active compounds were determined using nuclear magnetic resonance (NMR) spectra, UV, IR, and Mass Spectra. RESULTS: Six known compounds were isolated from M. latifolia fruit: O-methyloktadrenolon, alloevodionol, isopimpinellin, alloxanthoxyletin, methylevodionol, and N-methylflindersine. N-methylflidersine was the most active compound with IC50 value of 3.8 µg/ml while methylevodionol, isopimpinellin, and alloevodionol were less active. O-methyloktadrenolon and alloxanthoxyletin were moderately active with IC50 values of 10.9 and 21.72 µg/ml, respectively. N-methylflidersine decreased level of HCV NS3 protein expression in the cells. CONCLUSION: The alkaloid compound, N-methylflindersine which was isolated from M. latifolia possesses anti-HCV activity through post-entry inhibition and suppressed NS3 protein expression.

Two new 2-arylbenzofurans from Sesbania grandiflora L. and their cytotoxicity towards cancer cell.

Two new 2-arylbenzofurans, sesbagrandiflorain D (1) and E (2) along with two known 2-arylbenzofurans, spinosan A (3) and spinosan B (4) were isolated from the stem bark of Sesbania grandiflora L. The structure of two new compounds established by HRESIMS, 1 D NMR (1H, 13C) and 2 D NMR (HMQC, HMBC) spectra. Compounds (1-4) assayed for their cytotoxicity towards three human cancer cells (MCF-7, HeLa, and WiDr). Compound 1 showed very high activity against MCF-7 and WiDr with an IC50 value of 0.06 and 0.60 µg/mL, respectively.

Mesucalophylloidin, a new isoprenylated 4-phenylcoumarin from Mesua calophylloides (Ridl.) Kosterm.

A new isoprenylated 4-phenylcoumarin derivative, mesucalophylloidin (1) along with three known compounds, mammea A/BA cyclo F (2), calolongic acid (3) and isocalolongic acid (4) were isolated from the stem bark of Mesua calophylloides (Ridl.) Kosterm. Structures of all the compounds were elucidated using extensive spectroscopic methods, including UV, IR, HRESIMS, 1D and 2D NMR. Compounds 1-4 were evaluated for their cytotoxicity against P-388 cells, showing that compound 1 gave moderate activity with IC50 6.26 µg/mL.

Airlanggins A-B, two new isoprenylated benzofuran-3-ones from the stem bark of Calophyllum soulattri.

Two new isoprenylated benzofuran 3-ones, airlanggin A (1) and B (2) along with two known xanthones, ananixanthone (3) and trapezifolixanthone (4) were isolated from the stem bark of Calophyllum soulattri. Structures of all the compounds were elucidated using extensive spectroscopic methods, including UV, IR, HRESIMS, 1D and 2D NMR. Compounds 1-4 were evaluated for their cytotoxicity against P-388 cells, showing that compound 3 was the most active with IC50 0.68 µg/mL and compound 1 showed moderate activity with IC50 5.80 µg/mL.