New Cytotoxic Monotetrahydrofuran Annonaceous Acetogenins from <i>Annona </i><i>m</i><i>uricata</i>

Three new monotetrahydrofuran annonaceous acetogenins, muricin H (1), muricin I (2), and cis-annomontacin (3), along with five known acetogenins, annonacin, annonacinone, annomontacin, murisolin, and xylomaticin, were isolated from the seeds of Annona muricata. Additionally, two new monotetrahydrofuran annonaceous acetogenins, cis-corossolone (4) and annocatalin (5), together with four known ones, annonacin, annonacinone, solamin, and corossolone, were isolated from the leaves of this species. The structures of all new isolates were elucidated and characterized by spectral and chemical methods. These new acetogenins exhibited significant activity in in vitro cytotoxic assays against two human hepatoma cell lines, Hep G2 and 2,2,15. Compound 5 showed a high selectivity toward the Hep 2,2,15 cell line

Formaldehyde-Free Synthesis of Fully Bio-Based Multifunctional Bisbenzoxazine Resins from Natural Renewable Starting Materials

Although bio-based benzoxazines (BZs) have been explored widely as sustainable thermosetting resins, few high-performance BZs have been prepared completely from natural renewable resources. In this study we synthesized a fully bio-based multifunctional bisbenzoxazine (AP-fa-BZ) in high yield and purity from apigenin (AP), furfurylamine (fa), and benzaldehyde by using both solvent and solventless approaches. Fourier transform infrared (FTIR) spectroscopy, high-resolution mass spectrometry, and one- and two-dimensional nuclear magnetic resonance spectroscopy confirmed the chemical structure of AP-fa-BZ. We then used dynamic mechanical analysis, differential scanning calorimetry (DSC), thermogravimetric analysis, and in situ FTIR spectroscopy to examine the thermal characteristics of AP-fa-BZ before and after its ring-opening polymerization (ROP). DSC revealed that the temperature required for the formation of poly­(AP-fa-BZ) through ROP (236.3 °C) was significantly lower than that of a typical 4-phenyl-3,4-dihydro-2H-1,3-benzoxazine (Pa-type) monomer due to the positive catalytic effect of the phenolic OH groups in the AP structure. After thermal polymerization at 250 °C, the resulting poly­(AP-fa-BZ) possessed a high thermal decomposition temperature (Td10 = 395 °C), a high char yield (52 wt %), and a high glass transition temperature (Tg = 283 °C). Contact angle measurements revealed the tunable surface properties of AP-fa-BZ. Finally, the AP-fa-BZ resin functioned as an antibacterial agent against both Staphylococcus aureus and Escherichia coli

Anti-inflammatory Flavonoids from the Rhizomes of <i>Helminthostachys zeylanica</i>

Eight new prenylated flavonoids, ugonins M−T (1-8), together with five known compounds, ugonins J−L (9−11), 5,4′-dihydroxy-4′′,4′′-dimethyl-5′′-methyl-5′′H-dihydrofurano[2′′,3′′:6,7]flavanone, and quercetin, were isolated and purified from the rhizomes of Helminthostachys zeylanica. The structures of the new isolates were elucidated by spectroscopic and chemical methods. Compounds 1, 3, 5, 7, 8, and 11 showed inhibition of superoxide anion generation and elastase release by human neutrophils in response to formyl-l-methionyl-l-leucyl-l-phenylalanine/cytochalasin B (FMLP/CB)

Anti-inflammatory Flavonoids from the Rhizomes of <i>Helminthostachys zeylanica</i>

Eight new prenylated flavonoids, ugonins M−T (1-8), together with five known compounds, ugonins J−L (9−11), 5,4′-dihydroxy-4′′,4′′-dimethyl-5′′-methyl-5′′H-dihydrofurano[2′′,3′′:6,7]flavanone, and quercetin, were isolated and purified from the rhizomes of Helminthostachys zeylanica. The structures of the new isolates were elucidated by spectroscopic and chemical methods. Compounds 1, 3, 5, 7, 8, and 11 showed inhibition of superoxide anion generation and elastase release by human neutrophils in response to formyl-l-methionyl-l-leucyl-l-phenylalanine/cytochalasin B (FMLP/CB)

Discovering a Racemate Polycyclic Prenylated Acylphloroglucinol with Unprecedented Skeleton by an ESI-LCMS Analytical Approach

By an ESI-LC/MS analytical method, a racemate 1 consisting of a pair of unprecedented phloroglucinol enantiomers with a 5/6/5/5/6 fused ring system, (−)-garcinielliptone HG [((−)-1a] and (+)-garcinielliptone HH [(+)-1b], was obtained from the isolates of a CH2Cl2 extract of Garcinia subelliptica (heartwood). The gross structure of 1 was elucidated by spectroscopic methods and X-ray single-crystal diffraction data. The absolute configurations of 1a and 1b were unequivocally assigned by analysis on the calculated and experimental circular dichroism spectra and X-ray single-crystal diffraction data

Mono-tetrahydrofuran Annonaceous Acetogenins from <i>Annona squamosa</i> as Cytotoxic Agents and Calcium Ion Chelators

Eight new mono-tetrahydrofuran (THF)-type annonaceous acetogenins, squafosacins B, C, F, and G (1−4), squadiolins A−C (5−7), and cis-annotemoyin-1 (8), as well as eight known annonaceous acetogenins, glabranin, annotemoyins-1 and -2, bullatencin, cis-bullatencin, and uvariamicins-I, -II, and -III, were isolated from the seeds of Annona squamosa by HPLC. The structures of all new isolates were elucidated by using spectroscopic and chemical methods. Squadiolins A (5) and B (6) showed ng/mL potency against human Hep G2 hepatoma cells and significant cytotoxic activity against human MDA-MB-231 breast cancer cells. Squafosacin B (1) also exhibited significant cytotoxic activity against human Hep G2 and 3B hepatoma and MCF-7 breast cancer cells. In addition, the chelation of mono-THF acetogenins with calcium ions was investigated using isothermal titration calorimetry

Influenza A (H₁N₁) Antiviral and Cytotoxic Agents from <i>Ferula assa-foetida</i>

Two new sesquiterpene coumarins, designated 5′-acetoxy-8′-hydroxyumbelliprenin (1) and 10′R-acetoxy-11′-hydroxyumbelliprenin (2), and a new diterpene, 15-hydroxy-6-en-dehydroabietic acid (3), along with 27 known compounds, were isolated from a CHCl3-soluble extract of Ferula assa-foetida through bioassay-guided fractionation. The structures of the new metabolites 1−3 were identified by spectroscopic data interpretation and by the Mosher ester method. Compounds 4 and 6−13 showed greater potency against influenza A virus (H1N1) (IC50 0.26−0.86 μg/mL) than amantadine (IC50 0.92 μg/mL), and 11 exhibited the best potency (IC50 0.51, 2.6, and 3.4 μg/mL) of these compounds against the HepG2, Hep3B, and MCF-7 cancer cell lines, respectively

Biosynthesis of Vitroprocines by α‑Oxoamine Synthase and Oxidoreductase Identified from <i>Vibrio</i> sp. QWI-06

A specific α-oxoamine synthase (VsAOS-2) and an oxidoreductase (VsOR) identified from marine Vibrio sp. QWI-06 were involved in the decarboxylative condensation of l-tyrosine to lauroyl-CoA following the reduction of the ketone group to form vitroprocine-type compound 1. The intermediates and products were characterized through HR-MS and their MS/MS fragmentations. This study reveals the biosynthetic pathway of vitroprocines and provides a useful model for elucidating the reaction mechanism underlying the production of amino acid-polyketide derivatives in microorganisms

New Meroterpenoids from <i>Aspergillus terreus</i> with Inhibition of Cyclooxygenase‑2 Expression

Two novel meroterpenoids, yaminterritrems A (<b>1</b>) and B (<b>2</b>), were isolated from <i>Aspergillus terreus</i> collected from hot spring zones in Yang-Ming Mountain, Taiwan, and cultured at 40 °C. The structures of <b>1</b> and <b>2</b> were elucidated by NMR, MS spectral and X-ray crystallographic analyses. The biosynthetic route for <b>1</b> and <b>2</b> involving the conversion of the sesquiterpene with phenyl-α-pyrone is proposed. Besides, <b>2</b> exhibited a dose-dependent inhibitory effect on COX-2 expression in LPS-stimulated RAW264.7 macrophages

Withanolide-Based Steroids from the Cultured Soft Coral <i>Sinularia brassica</i>

Seven novel withanolides, sinubrasolides A–G (<b>1</b>–<b>7</b>), have been isolated from the cultured soft coral <i>Sinularia brassica</i>. The structures of the new metabolites were determined by extensive spectroscopic analyses, and the absolute configuration of <b>1</b> was established by X-ray crystallographic analysis. The cytotoxicities of compounds <b>1</b>–<b>7</b> against a limited panel of cancer cell lines also were determined