Bioassay-guided fractionation of the culture extract of Aspergillus wentii EN-48, an endophytic fungus isolated from an unidentified marine brown algal species of the genus Sargassum, led to the isolation of three new tetranorlabdane diterpenoids, asperolides A-C (1-3), and five related derivatives (4-8). The structures of these compounds were established on the basis of spectroscopic interpretation, and compound 1 was confirmed by X-ray crystallographic analysis. The absolute configuration of 1 was determined by application of the modified Mosher's method. An X-ray structure for wentilactone B (6) is also reported. Compounds 1-8 were evaluated for cytotoxic and antibacterial activities.
Multifunctional micelles for cancer cell targeting, distribution imaging, and anticancer drug delivery were prepared from an environmentally‐sensitive graft copolymer, poly(N‐isopropyl acrylamide‐co‐methacryl acid)‐g‐poly(D,L‐lactide) (P(NIPAAm‐co‐MAAc)‐g‐PLA), a diblock copolymer, methoxy poly(ethylene glycol)‐b‐poly(D,L‐lactide) (mPEG‐PLA) and two functionalized diblock copolymers, galactosamine‐PEG‐PLA (Gal‐PEG‐PLA) and fluorescein isothiocyanate‐PEG‐PLA (FITC‐PEG‐PLA). Anticancer drug, free base doxorubicin (Dox) was incorporated into the inner core of multifunctional micelles by dialysis. From the drug release study, a change in pH (from pH 7.4 to 5.0) deformed the structure of the inner core from that of aggregated P(NIPAAm‐co‐MAAc), causing the release of a significant quantity of doxorubicin (Dox) from multifunctional micelles. Multifunctional micelles target specific tumors by an asialoglycoprotein (HepG2 cells)‐Gal (multifunctional micelle) receptor‐mediated tumor targeting mechanism. This mechanism then causes intracellular pH changes which induce Dox release from multifunctional micelles and that micelles have strong effects on the viability of HepG2 cells and are abolished by galactose. Confocal laser scanning microscopy (CLSM) reveals a clear distribution of multifunctional micelles. With careful design and sophisticated manipulation, polymeric micelles can be widely used in cancer diagnosis, cancer targeting, and cancer therapy simultaneously.
Four new β-carboline alkaloids, designated marinacarbolines A-D (1-4), two new indolactam alkaloids, 13-N-demethyl-methylpendolmycin (5) and methylpendolmycin-14-O-α-glucoside (6), and the three known compounds 1-acetyl-β-carboline (7), methylpendolmycin (8), and pendolmycin (9) were obtained from the fermentation broth of Marinactinospora thermotolerans SCSIO 00652, a new actinomycete belonging to the family Nocardiopsaceae. Their structures were elucidated by extensive MS and 1D and 2D NMR spectroscopic data analyses. The structure of compound 1 was further confirmed by single-crystal X-ray crystallography. The new compounds 1-6 were inactive against a panel of eight tumor cell lines (IC50>50 μM) but exhibited antiplasmodial activities against Plasmodium falciparum lines 3D7 and Dd2, with IC50 values ranging from 1.92 to 36.03 μM.
Five new C-glycoside angucyclines, named grincamycins B−F (1−5), and a known angucycline antibiotic, grincamycin (6), were isolated from Streptomyces lusitanus SCSIO LR32, an actinomycete of deep sea origin. The structures of these compounds were elucidated on the basis of extensive spectroscopic analyses, including MS and 1D and 2D NMR experiments. All compounds except grincamycin F (5) exhibited in vitro cytotoxicities against the human cancer cell lines HepG2, SW-1990, HeLa, NCI-H460, and MCF-7 and the mouse melanoma cell line B16, with IC 50 values ranging from 1.1 to 31 μM.
Thick cathodes with aligned pore arrays in the predominant ion transport direction made by ice templating provided high areal and gravimetric capacities.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.