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Poor selectivity to tumor cells is a major drawback in the clinical application of the antitumor drug doxorubicin (DOX). Peptide–drug conjugates (PDCs) constructed by modifying antitumor drugs with peptide ligands that have high affinity to certain overexpressed receptors in tumor cells are increasingly assessed for their possibility of tumor-selective drug delivery. However, peptide ligands composed of natural L-configuration amino acids have the defects of easy enzymatic degradation and insufficient biological stability. In this study, two new PDCs (LT7-SS-DOX and DT7-SS-DOX) were designed and synthesized by conjugating a transferrin receptor (TfR) peptide ligand LT7 (HAIYPRH) and its retro-inverso analog DT7 (hrpyiah), respectively, with DOX via a disulfide bond linker. Both conjugates exhibited targeted antiproliferative effects on TfR overexpressed tumor cells and little toxicity to TfR low-expressed normal cells compared with free DOX. Moreover, the DT7-SS-DOX conjugate possessed higher serum stability, more sustained reduction-triggered drug release characteristics, and stronger in vitro antiproliferative activity as compared to LT7-SS-DOX. In conclusion, the coupling of antitumor drugs with the DT7 peptide ligand can be used as a promising strategy for the further development of stable and efficient PDCs with the potential to facilitate TfR-targeted drug delivery.

In the course of synthesizing 3-demethyltylophorine (1) by Lewis acid catalyzed intramolecular Friedel-Crafts reaction starting from N-(3-hydroxy-2,6,7-trimethoxy-phenanthr-9-ylmethyl)-2-chloromethylpyrrolidine, two chlorinated phenanthrene derivatives N-(4,10-dichloro-3-hydroxy-2,6,7-trimethoxyphenanthr-9-ylmethyl)-2-chloromethylpyrrolidine (4) and N-(4-chloro-3-hydroxy-2,6,7-trimethoxyphenanthr-9-ylmethyl)-2-chloromethylpyrrolidine (5) were obtained. The structures of these compounds were determined by spectroscopic analysis.

A series of phenanthrene-based tylophorine derivatives (PBTs) were synthesized and their cytotoxic activities against the H460 human large-cell lung carcinoma cell line were evaluated. Among these compounds, N-(3-hydroxy-2,6,7-tri-methoxyphenanthr-9-ylmethyl)-L-prolinol (5a), and N-(3-hydroxy-2,6,7-trimethoxy-phenanthr-9-ylmethyl)-L-valinol (9) exhibited good activities, with IC50 values of 11.6 and 6.1 mM, respectively.

Traditional Chinese medicine considers Lonicerae japonicae flos to have antibacterial detoxification, liver protection, and gallbladder protection. At present, studies have proven that Lonicerae japonicae flos has a good therapeutic effect on liver injury. Therefore, to confirm the clinical applicability of Lonicerae japonicae flos in the treatment of liver injury, we were the first to compare the pharmacokinetics of an oral ethanol extract of Lonicerae japonicae flos in normal rats and carbon tetrachloride-induced liver injury model rats. A method was developed for the simultaneous determination of 3-caffeoylquinic acid, 4-caffeoylquinic acid, 5-caffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, protocatechuic acid, Sweroside, and Secoxyloganin in rat plasma by ultra-performance liquid chromatography tandem mass spectrometry. The results show that the method is reliable and reproducible and can be used for quantitative determination of biological samples. The pharmacokinetic parameters showed that the area under the concentration–time curve of eight compounds in the model group was significantly increased. The results showed that the total absorption of the active components of Lonicerae japonicae flos in the blood increased, the clearance rate slowed down, and the bioavailability of Lonicerae japonicae flos increased in liver injury diseases.

It is highly desired to enhance charge separation and O2 adsorption of the pyropheophorbide-a (Ppa) to promote visible-light activity and stability. Herein, Ppa modified 001-facet-exposed TiO2 nanosheets (Ppa/001T) nanocomposites with different weight ratios were fabricated via the self-assembly approach by OH induced. Compared with the bare Ppa, the 8% amount optimized 8Ppa/001T sample displayed 41-fold enhanced activity for degradation of Ametryn (AME) under visible-light irradiation. The promoted photoactivities could be attributed to the accelerated charge carrier’s separation by coupling TiO2 as thermodynamic platform for accepting the photoelectrons with high energy from Ppa and the promoted O2 adsorption because of the residual fluoride on TiO2. As for this, a distinctive two radicals (•O2− and •OH) involved pathway of AME degradation is carried out, which is different from the radical pathway dominated by •O2− for the bare Ppa. This work is of utmost importance since it gives us detailed information regarding the charge carrier’s separation and the impact of the radical pathway that will pave a new approach toward the design of high activity visible-light driven photocatalysts.

In the course of synthesizing 3-demethyltylophorine (1) by Lewis acid catalyzed intramolecular Friedel-Crafts reaction starting from N-(3-hydroxy-2,6,7-trimethoxyphenanthr- 9-ylmethyl)-2-chloromethylpyrrolidine, two chlorinated phenanthrene derivatives N-(4,10-dichloro-3-hydroxy-2,6,7-trimethoxyphenanthr-9-ylmethyl)-2-chloromethylpyrrolidine (4) and N-(4-chloro-3-hydroxy-2,6,7-trimethoxyphenanthr-9-ylmethyl)-2-chloromethylpyrrolidine (5) were obtained. The structures of these compounds were determined by spectroscopic analysis. [ABSTRACT FROM AUTHOR]

A series of phenanthrene-based tylophorine derivatives (PBTs) were synthesized and their cytotoxic activities against the H460 human large-cell lung carcinoma cell line were evaluated. Among these compounds, N-(3-hydroxy-2,6,7-trimethoxyphenanthr-9-ylmethyl)-L-prolinol (5a), and N-(3-hydroxy-2,6,7-trimethoxyphenanthr-9-ylmethyl)-L-valinol (9) exhibited good activities, with IC50 values of 11.6 and 6.1 μM, respectively. [ABSTRACT FROM AUTHOR]

In this work, the anticancer activity of chamaejasmine was studied by evaluating its in vitro cytotoxicity against several human cancer cell lines (MCF-7, A549, SGC-7901, HCT-8, HO-4980, Hela, HepG2, PC-3, LNCap, Vero and MDCK) using the MTT assay. Results indicated chamaejasmine showed more notable anticancer activity than taxol against PC-3 cells, with IC50 values of 2.28 and 3.98 µM, respectively. Furthermore, Western blot analysis showed that chamaejasmine was able to increase the expression of β-tubulin, but not α-tubulin. In silico simulations indicated that chamaejasmine specifically interacts with the active site which is located at the top of β-tubulin, thanks to the presence of strong hydrophobic effects between the core templates and the hydrophobic surface of the TB active site. The binding energy (Einter) was calculated to be −164.77 kcal·mol−1. Results presented here suggest that chamaejasmine possesses anti-cancer properties relating to β-tubulin depolymerization inhibition, and therefore is a potential source of anticancer leads for the pharmaceutical industry.