Clerodane-type Diterpene Glycosides from Dicranopteris pedata

Three new clerodane-type diterpene glycosides, (5R,6S,8R,9S,10R)-6-O-[β-d-glucopyranosyl-(1 → 4)-α-l-rhamnopyranosyl]cleroda-3,13(16),14-diene (1), (5R,6S,8R,9S,10R,13S)-6-O-[β-d-glucopyranosyl-(1 → 4)-α-l-rhamnopyranosyl]-2-ox-oneocleroda-3,13-dien-15-ol (2), (5R,6S,8R,9S,10R)-6-O-[β-d-glucopyranosyl-(1 → 4)-α-l-rhamnopyranosyl]-(13E)-2-oxoneocleroda-3,14-dien-13-ol (3), together with two known compounds 4 and 5 were isolated from Dicranopteris pedata. The structures of these compounds were elucidated by detailed spectroscopic analysis, and the absolute configuration of compound 2 was determined by ECD calculations. In addition, compound 1 exhibited weak inhibitory activities against SMMC-7721, MCF-7 and SW480. Graphic Abstract

New Sulfoxide-Containing Derivatives from the Resin of Ferula sinkiangensis

Four undescribed sulfoxide-containing derivatives, sinkiangenoxides A and B, (2Z, 4E)-sinkiangenoxide C, and (2E, 4E)-sinkiangenoxide C (1 – 4), and one known compound, 1-(methylthio)propyl (E)-1-propenyl disulfide (5), were isolated from the resin of Ferula sinkiangensis. Their structures were determined based on spectroscopic methods, including IR, UV, HRESIMS, NMR, and CD analysis. Compounds 2 – 4 showed moderate cytotoxic activities against four human cancer cell lines with IC50 values ranging from 15.0 to 40.3 µM. Sinkiangenoxide B (2) was shown to induce apoptosis in HepG2 cells. In addition, compound 5 effectively attenuated lipopolysaccharide-induced nitric oxide release and TNF-α, IL-1β, IL-6, and IL-10 expression.

Jatrophane Diterpenoids from the Seeds of Euphorbia peplus with Potential Bioactivities in Lysosomal-Autophagy Pathway

Euphopepluanones F − K (1 − 4), four new jatrophane type diterpenoids were isolated from the seeds of Euphorbia peplus, along with eight known diterpenoids (5 − 12). Their structures were established on the basis of extensive spectroscopic analysis and X-ray crystallographic experiments. The new compounds 1 − 4 were assessed for their activities to induce lysosomal biogenesis through LysoTracker Red staining. Compound 2 significantly induced lysosomal biogenesis. In addition, compound 2 could increase the number of LC3 dots, indicating that it could activate the lysosomal-autophagy pathway. Graphic Abstract

New Pyrrolobenzoxazine Sesquiterpenoid Derivatives from the Fungus Talaromyces trachyspermus

Three new pyrrolobenzoxazine sesquiterpenoids, talatrachyoxazines A – C (1 – 3), together with fourteen known compounds (4 – 17), were isolated from the fungus Talaromyces trachyspermus EU23. Their structures were identified by spectroscopic evidence and mass spectrometry. The absolute configurations of 1 – 3 were determined by NOESY data and comparison of their calculated and experimental electronic circular dichroism (ECD) spectra. Compound 1 showed cytotoxic activity against HelaS3, KB, HT-29, MCF-7, and HepG2 cell lines with IC50 values of 7, 11, 10, 12, and 10 µM, respectively. Compounds 1 and 14 showed weak antibacterial activity against the gram-positive bacteria Bacillus cereus and Bacillus subtilis, while 1 – 3 and 14 showed weak antibacterial activity against the gram-negative bacterium Pseudomonas aeruginosa. In addition, compound 1 showed weak antibacterial activity against Escherichia coli.

Compounds Isolated From the Fruits of Xanthium strumarium, Including a New Neo-Lignan, and Their Anticancer Effects

A new neo-lignan, (7′ S,8 ′R)-4′,5′,9′-trihydroxy-4,6-dimethoxy-5,8′-oxyneolign-7-en-9-al (1), along with 5 known compounds (2-6), were isolated from the fruits of Xanthium strumarium. Their structures were elucidated by extensive spectroscopic methods. All the isolates were evaluated for in vitro cytotoxicities against the human cancer lines HepG2, A549, HCT-116, and SGC-7901. Compounds 1 and 3 showed potent antiproliferative effects against A549 cancer cells with half-maximal inhibitory concentration (IC50) values of 11.2 and 8.3 µM, respectively. In addition, compound 3 exhibited moderate cytotoxicity to SGC-7901 cancer cells, with an IC50 value of 12.9 µM.

Synthesis and Anti-Saprolegnia Activity of New 2’,4’-Dihydroxydihydrochalcone Derivatives

In the present study, seven 2’,4’-dihydroxydihydrochalcone derivatives (compounds 3–9) were synthesized and their capacity as anti-Saprolegnia agents were evaluated against Saprolegnia parasitica, S. australis, S. diclina. Derivative 9 showed the best activity against the different strains, with minimum inhibitory concentration (MIC) and minimum oomyceticidal concentration (MOC) values between 100–175 μg/mL and 100–200 μg/mL, respectively, compared with bronopol and fluconazole as positive controls. In addition, compound 9 caused damage and disintegration cell membrane of all Saprolegnia strains over the action of commercial controls.

Synthesis and herbicidal activities of aryloxyacetic acid derivatives as HPPD inhibitors

A series of aryloxyacetic acid derivatives were designed and synthesized as 4-hydoxyphenylpyruvate dioxygenase (HPPD) inhibitors. Preliminary bioassay results reveal that these derivatives are promising Arabidopsis thaliana HPPD (AtHPPD) inhibitors, in particular compounds I12 (K i = 0.011 µM) and I23 (K i = 0.012 µM), which exhibit similar activities to that of mesotrione, a commercial HPPD herbicide (K i = 0.013 µM). Furthermore, the newly synthesized compounds show significant greenhouse herbicidal activities against tested weeds at dosages of 150 g ai/ha. In particular, II4 exhibited high herbicidal activity for pre-emergence treatment that was slightly better than that of mesotrione. In addition, compound II4 was safe for weed control in maize fields at a rate of 150 g ai/ha, and was identified as the most potent candidate for a novel HPPD inhibitor herbicide. The compounds described herein may provide useful guidance for the design of new HPPD inhibiting herbicides and their modification.

Synergistic Interactions of Indole-2-Carboxamides and β-Lactam Antibiotics against Mycobacterium abscessus

ABSTRACT New drugs or therapeutic combinations are urgently needed against Mycobacterium abscessus. Previously, we demonstrated the potent activity of indole-2-carboxamides 6 and 12 against M. abscessus. We show here that these compounds act synergistically with imipenem and cefoxitin in vitro and increase the bactericidal activity of the β-lactams against M. abscessus. In addition, compound 12 also displays synergism with imipenem and cefoxitin within infected macrophages. The clinical potential of these new drug combinations requires further evaluation.

Preparation of anthracene-based tetraperimidine hexafluorophosphate and selective recognition of chromium(III) ions

A novel anthracene-based tetraperimidine hexafluorophosphate 3 was prepared, and its structure was determined through X-ray analysis, HRMS as well as 1H and 13C NMR spectroscopy. In the cationic moiety of 3, two (N-ethylperimidinyl–C2H4)2NCH2– arms were attached to the 9- and 10-positions of anthracene. In addition, compound 3 was used as a chemosensor to research the ability to recognize Cr3+ through fluorescence and UV titrations, HRMS, as well as 1H NMR and IR spectroscopy. The results indicate that 3 is an effective chemosensor for Cr3+.

Bioactive Dimeric Abietanoid Peroxides from the Bark of Cryptomeria japonica

Three new dimeric abietane-type diterpenoids, abieta-6,8,11,13-tetraen-12-yl 12-hydroxyabieta-8,11,13-trien-7α-yl peroxide (1), abieta-6,8,11,13-tetraen-12-yl 12-hydroxyabieta-8,11,13-trien-7β-yl peroxide (2), and 12-hydroxyabieta-8,11,13-trien-7β-yl 7-oxoabieta-5,8,11,13-tetraen-12-yl peroxide (3), together with four known abietane-type diterpenoids (4–7) were isolated from the methanol extract of the bark of Cryptomeria japonica. Their structures were elucidated on the basis of spectroscopic analysis and comparison of NMR data with those of known analogues. At a concentration of 50 μM, compounds 1, 2, and 3 showed 26.2%, 23.6%, and 35.7% inhibition towards xanthine oxidase enzyme, respectively. In addition, compound 3 also showed 24.9% inhibition toward angiotensin-converting enzyme (ACE).