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Despite great advances, the development of cancer drugs that can efficiently kill cancer cells while protecting noncancer cells has not been achieved. By using only dietary antioxidants vitamin C (VC) and (R)-(+)-lipoic acid (LA), we herein develop a nanodrug VC@cLAV featuring the above function. After entering cells, cLAV dissociates into LA and DHLA (dihydrolipoic acid, reduced form of LA) and releases VC and DHA (dehydroascorbate, oxidized form of VC). In cancer cells, the two redox pairs recycle each other and dramatically promote the intracellular reactive oxygen species production to kill cancer cells at low doses comparable to cytotoxic drugs. Oppositely in noncancer cells, the LA/DHLA and VC/DHA pairs exert anti-oxidant action to actively protect the organism by preventing the normal cells from oxidative stress and repairing cells suffering from oxidative stress. When compared with the first-line cytotoxic drug, VC@cLAV displayed superior therapeutic outcomes yet without side effects in diverse tumor models including patient-derived xenograft (PDX). This drug with efficient cancer cell killing and noncancer cell protection represents a new cancer therapy.

Six new acyclic diterpenoids named Aphanamixins A-F (1-6), together with two known compounds of nemoralisin and nemoralisin C, were isolated from the stem bark of Aphanamixis polystachya (WALL) J. N. BARKER. Their structures were established through a comprehensive analysis of NMR spectroscopic data and high resolution mass spectrometric data. The absolute configurations of carbon stereocenters were determined by means of auxiliary chiral α-methoxy-α-(trifluoromethyl)phenylacetic acid (MTPA) derivatives and circular dichroism (CD), respectively. All the new isolates were tested for their antiproliferative activity against HepG2, AGS, MCF-7, and A-549 cancer cell lines and they exhibited weak cytotoxicities (IC 50 >10 µM). Moreover, we highlighted that the six new diterpenoids characterized by acyclic skeleton was rarely seen in nature.

A series of mesoporous CeZrTiO x catalysts were prepared by a facile hydrothermal method. Compared with CeTiO x catalysts synthesized under the same conditions, the catalytic activity and anti-SO2 performance of the Ce1Zr1TiO x catalyst are greatly improved, and at the gas hourly space velocity (GHSV) of 60 000 h–1, the NO x removal efficiency is maintained at 90% in the temperature range of 290–500 °C. The catalytic effect of ZrO2 on the Ce–Ti catalyst NH3-SCR activity was elucidated through a series of characterizations. The results revealed that the doping of Zr could significantly improve and optimize the structure of Ce–Ti catalysts. At the same time, due to the doping of Zr, the synergistic effect between Ce and Zr in the CeZrTiO x catalyst can effectively increase oxygen mobility, total acid content, and surface adsorbed oxygen species and lead to a larger pore volume. In addition, the introduction of ZrO2 made the transformation of Ce4+ into Ce3+ more obvious, and the 2Ce4+ + Zr2+ ↔ 2Ce3+ + Zr4+ reaction greatly improved the reducibility of Ce1Zr1TiO x . Among them, the improvement of SCR performance and H2O/SO2 tolerance is due to the electronic interaction between Zr and Ce.

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