Correction: A combined crystallography and DFT study on ring-shaped cucurbit[]urils: structures, surface character, and host-guest recognition.

[This corrects the article DOI: 10.1039/D2RA00797E.].

Correction: A theoretical study on the on-off phosphorescence of novel Pt(ii)/Pt(iv)-bisphenylpyridinylmethane complexes.

[This corrects the article DOI: 10.1039/D2RA03060H.].

Study of the electronic effect and quantitative spectra predictions of -methoxyaniline-terminated monoazonaphthols: a combined experimental and DFT study.

A combined experimental and density functional theory (DFT) study on the UV-Vis spectra of -methoxyaniline-terminated mono azo dyes was conducted. By applying time-dependent-DFT calculations, details of excitation processes were determined and visualization by hole-electron analysis was undertaken. Fragment-divided analysis revealed the contributions of different parts of the structures for the UV-Vis spectra, that richer/poorer electron density on aromatic rings lead to greater/less maximum absorption wavelengths () and larger/smaller half peak width ().

A theoretical study on the on-off phosphorescence of novel Pt(ii)/Pt(iv)-bisphenylpyridinylmethane complexes.

An in-depth theoretical study on the Pt(ii)/Pt(iv)-bisphenylpyridinylmethane complexes was carried out, which focused on the geometric/electronic structures, excitation procedures, on-off phosphorescence mechanisms, and structure-optical performance relationships. The key roles of the linkages (LK) connected in the middle of phenylpyridines were carefully investigated using multiple wavefunction analysis methods, such as non-covalent interaction (NCI) visualizations and natural bond orbital (NBO) studies. The phosphorescence-off phenomenon was considered by hole-electron analysis and visualizations, spin-orbit coupling (SOC) studies, and NBO analysis.

A combined crystallography and DFT study on ring-shaped Cucurbit[]urils: structures, surface character, and host-guest recognition.

A combined crystallography and DFT study of cucurbit[]urils ( = 5-8, 10) was carried out, and PBE0 was certified to be the most rational density functional method for optimization task. Steric hindrance and electronic effect of the hindered lone pair electrons in cucurbit[]urils were qualitatively measured by bond order analysis, lone pair electron (LP) visualization and electrostatic potential (ESP) study. Together with energy decomposition analysis of some selected host-guest systems, we quantitatively verified the effect of size/cavity and noncovalent interaction in host-guest recognition.

Chemodivergent Couplings of N-Arylureas and Methyleneoxetanones via Rh(III)-Catalyzed and Solvent-Controlled C-H Activation.

The efficient couplings of diverse N-arylureas and methyleneoxetanones have been realized via Rh(III)-catalyzed and solvent-controlled chemoselective C-H functionalization, which involved the tunable β-H elimination and β-O elimination processes, thereby giving divergent access to quinolin-2(1 H)-ones and ortho-allylated N-arylureas with broad substrate compatibility and good functional group tolerance. the divergent synthetic utilities of the transformations have also been exemplified by subsequently tandem C-H allylation, unsymmetrical C-H functionalization, alternative reaction mode, as well as removal of the carbamoyl group.

Synthesis and Photodynamic Activity of Peri-xanthenoxanthene Derivatives.

Photodynamic therapy (PDT) is a modern cancer therapy. But it is still difficult to obtain ideal photosensitizers. We synthesized six new peri-xanthenoxanthene derivatives rapidly and efficiently using solid-phase carbon-bath microwave irradiation technology, and investigated their in vitro photodynamic antitumor activity with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.

A simple functionalized silica microsphere for fast PETN vapor detection based on fluorescence color changes via a catalyzed oxidation process.

In this work, we report a new fluorescent material for pentaerythritol tetranitrate (PETN) vapor detection. A series of fluorene substituted vinyl-SiO microspheres with different ratios has been designed and easily synthesized. Sensing films on quartz plates were obtained by a solid phase transfer method.

Bran-New Four-Molecule and Five-Molecule Cascade Reactions for One-Pot Synthesis of Pyrano[3,2-]chromen-5-ones and Spiro[benzo[][1,4]diazepine-2,2'-pyrano[3,2-]chromen]-5'-ones under Catalyst- and Solvent-Free Conditions.

Herein, two versatile bran-new methods have been developed for building three new kinds of complicated-framework compounds including 2,4,4-trimethyl-2-(phenylamino)-3,4-dihydro-2,5-pyrano[3,2-]chromen-5-ones, 4,4,4',4'-tetramethyl-1,3,3',4,4',5-hexahydro-5'-spiro-[benzo[][1,4]diazepine-2,2'-pyrano[3,2-]-chromen]-5'-ones, and 2,2,4',4'-tetramethyl-2,3,3',4'-tetrahydro-5,5'-spiro[benzo[][1,4]-oxazepine-4,2'-pyrano[3,2-]chromen]-5'-ones in a one-pot manner via four-molecule and five-molecule cascade reactions of commercially available 4-hydroxychromen-2-one, substituted anilines, and acetone. In consideration of these impressive features including no need of additional catalysts and solvents, moderate to good yields, excellent site-selectivity, and broad substrate/functional group tolerance, we believe that the two present protocols should have the potential for broad synthetic utility.

Analysis of volatile components in Dalbergia cochinchinensis Pierre by a comprehensive two-dimensional gas chromatography with mass spectrometry method using a solid-state modulator.

Volatile components in Dalbergia cochinchinensis Pierre were analysed using a comprehensive two-dimensional gas chromatography with mass spectrometry method featuring a new solid-state modulator. Compared to one-dimensional gas chromatography, the number of detected peaks were significantly increased. A total of 45 major compounds were identified in this study and the forward and reverse match factors of these compounds were both above 800.

Preclinical Study of Novel Curcumin Analogue SSC-5 Using Orthotopic Tumor Xenograft Model for Esophageal Squamous Cell Carcinoma.

Purpose: Tumor xenograft model is an indispensable animal cancer model. In esophageal squamous cell carcinoma (ESCC) research, orthotopic tumor xenograft model establishes tumor xenograft in the animal esophagus, which allows the study of tumorigenesis in its native microenvironment.

Materials And Methods: In this study,we described two simple and reproducible methods to develop tumor xenograft at the cervical or the abdominal esophagus in nude mice by direct injection of ESCC cells in the esophageal wall.

Study on the design, synthesis and structure-activity relationships of new thiosemicarbazone compounds as tyrosinase inhibitors.

52 Structure-based thiosemicarbazone compounds bearing various substituted-lipophilic part, including substituted-benzaldehyde, substituted-phenylalkan-1-one and their biphenyl-type thiosemicarbazone analogs, were designed, synthesized and evaluated as new tyrosinase inhibitors. The results demonstrated that 22 compounds have potent inhibitory activities against tyrosinase with the IC value of lower than 1.0 μM.

Exploration of metal-organic framework MOF-177 coated fibers for headspace solid-phase microextraction of polychlorinated biphenyls and polycyclic aromatic hydrocarbons.

Metal-organic frameworks (MOFs) have received much attention in analytical science for their large langmuir surface and high thermostability. Herein MOF-177-coated solid-phase micro-extraction (SPME) fibers were fabricated on etched stainless steel by an adhensive method, and applied to the enrichment of polychlorinated biphenyls (PCB01, PCB05, PCB29, PCB47, PCB98, PCB154, PCB171, PCB201) and polycyclic aromatic hydrocarbons (ANY, ANA, FLU, PHE, ANT, FLT, PYR) from environmental water samples. Several parameters affecting the extraction efficiency were optimized prior to the gas chromatography-mass spectrometry analysis, including extraction temperature and time, desorption time, stirring rate and salt addition.

[Study on Glycosides Constituents from Guangdong Liangcha Granules(II)].

Objective: To study the glycosides from Guangdong Liangcha Granules.

Methods: The chemical constituents were isolated by various chromatographic techniques and the structures of chemical constituents were identified by spectroscopic analysis and literature.

Results: Six compounds were isolated and identified as ilexoside B (1), asprellanosides B (2), asprellanoside A (3), 4', 5 ,7 -tri- hydroxyflavone-6-O-β3-D-glucopyranosyl ester(4), isoviolanthin (5),3-O-methy-lellagic acid 4'-O-rhamnopyranoside (6).

Rh(III)-catalyzed and alcohol-involved carbenoid C-H insertion into N-phenoxyacetamides using α-diazomalonates.

Here we report a new and mild Rh(III)-catalyzed and alcohol-involved carbenoid C-H insertion into N-phenoxyacetamides using α-diazomalonates. This reaction provided a straightforward way for installing both an α-quaternary carbon center and a free-OH moiety into the phenyl ring, thus giving access to useful 2-(2-hydroxyphenyl)-2-alkoxymalonates with good substrate/functional group tolerance.

Structure-based modification of 3-/4-aminoacetophenones giving a profound change of activity on tyrosinase: from potent activators to highly efficient inhibitors.

In this study, we developed 3-/4-aminoacetophenones and their structure-based 3-/4-aminophenylethylidenethiosemicarbazide derivatives, respectively, as novel tyrosinase activators and inhibitors. Notably, all the obtained thiosemicarbazones displayed more potent tyrosinase inhibitory activities than kojic acid. Especially, compound 7k was found to be the most active tyrosinase inhibitor with IC50 value of 0.

Rational design, synthesis and structure-activity relationships of 4-alkoxy- and 4-acyloxy-phenylethylenethiosemicarbazone analogues as novel tyrosinase inhibitors.

In continuing our program aimed to search for potent compounds as highly efficient tyrosinase inhibitors, here a series of novel 4-alkoxy- and 4-acyloxy-phenylethylenethiosemicarbazone analogues were designed, synthesized and their biological activities on mushroom tyrosinase were evaluated. Notably, most of compounds displayed remarkable tyrosinase inhibitory activities with IC50 value of lower than 1.0μM.

One-pot cascade synthesis of N-methoxyisoquinolinediones via Rh(III)-catalyzed carbenoid insertion C-H activation/cyclization.

Here a new, mild and versatile method for one-pot cascade synthesis of diverse N-methoxyisoquinolinediones via Rh(III)-catalyzed regioselective carbenoid insertion C-H activation/cyclization of N-methoxybenzamides with α-diazotized Meldrum's acid has been achieved. Extension of the developed Rh(III) catalysis for building new analogs of the marketed drug Edaravone has also been demonstrated.

Design, synthesis and biological evaluation of hydroxy- or methoxy-substituted 5-benzylidene(thio) barbiturates as novel tyrosinase inhibitors.

Here a new class of hydroxy- or methoxy-substituted 5-benzylidene(thio)barbiturates were designed, synthesized and their inhibitory effects on the diphenolase activity of mushroom tyrosinase were evaluated. The results showed that several compounds had more potent tyrosinase inhibitory activities than the widely used tyrosinase inhibitor kojic acid (IC50=18.25μM).

Synthesis and evaluation of some new aza-B-homocholestane derivatives as anticancer agents.

Using analogues of some marine steroidal oximes as precursors, a series of aza-B-homocholestane derivatives possessing different substituted groups at the 3-position of the steroidal nucleus were synthesized. Their biological activity against cancer cell proliferation was determined with multiple cancer cell lines. Aza-B-homocholestane derivatives possessing 3-hydroxyl, 3-hydroximino and 3-thiosemicarbazone groups displayed remarkable cytotoxicity to cancer cells via apoptosis inducing mechanism.

Design, synthesis and evaluation of N13-substituted evodiamine derivatives against human cancer cell lines.

Attempting to improve the anticancer activity and solubility of evodiamine in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) solutions, thirty-eight N13-substituted evodiamine derivatives were designed, synthesized and tested for antitumor activities against six kinds of human cancer cell lines, namely prostate cancer (DU-145 and PC-3), lung cancer (H460), breast cancer (MCF-7), colon cancer (HCT-5) and glioblastoma (SF-268). The solubility of these compounds in SGF and SIF solutions was evaluated, and apoptosis induced by 2-2, 2-3, 2-16 and 3-2 was determined. The results showed: (1) among all compounds examined, 2-16 showed the highest antitumor activity and a broader spectrum of activity, with IC50 values ranging from 1-2 µM; (2) their solubility was obviously improved; (3) 2-3, 2-16 and 3-2 had a significant impact inducing apoptosis in some cancer cell lines.

Synthesis and neuroprotective action of xyloketal derivatives in Parkinson's disease models.

Parkinson's disease (PD) is the second most common neurodegenerative disease affecting people over age 55. Oxidative stress actively participates in the dopaminergic (DA) neuron degeneration of PD. Xyloketals are a series of natural compounds from marine mangrove fungus strain No.

Synthesis and evaluation of some 17-acetamidoandrostane and N,N-dimethyl-7-deoxycholic amide derivatives as cytotoxic agents: structure/activity studies.

Using pregnenolone and 7-deoxycholic acid as starting materials, some 17-acetamidoandrostane and N,N-dimethyl-7-deoxycholic amide derivatives were synthesized. The cytotoxicity of the synthesized compounds was tested in vitro against two tumor cell lines: SGC 7901 (human gastric carcinoma) and Bel 7404 (human liver carcinoma). The result showed that the blockage of the interaction of the amide group with outside groups might cause a decrease of the cytotoxicity, and an O-benzyloximino group at the 3-position of N,N-dimethyl-7-deoxycholic amide could enhance the cytotoxic activity of the compound.

Design, synthesis and in vitro and in vivo antitumor activities of novel bivalent β-carbolines.

A series of bivalent β-carbolines with a spacer of three to ten methylene units between the indole nitrogen was synthesized and evaluated as antitumor agents. The results demonstrated that compounds 18c, 21b, 25a and 31b exhibited strong cytotoxic activities with IC(50) value of lower than 20 μM against four tumor cell lines. Acute toxicities and antitumor efficacies of the selected compounds in mice were also evaluated, compounds 18b, 21b, 26a and 31b exhibited potent antitumor activities with tumor inhibition rate of over 40% in animal models.

Synthesis and biological evaluation of 1,9-disubstituted β-carbolines as potent DNA intercalating and cytotoxic agents.

A series of novel 1,9-disubstituted β-carbolines was designed, synthesized and evaluated as cytotoxic and DNA intercalating agents. Compounds 7b, 7c, 8b and 8c exhibited the most potent cytotoxic activities with IC(50) values of lower than 20 μM against ten human tumor cell lines. The results indicated that (1) the 3-chlorobenzyl and 3-phenylpropyl substituents in position-9 of β-carboline nucleus were the suitable pharmacophoric group giving rise to significant antitumor agents; (2) the length of the alkylamino side chain moiety affected their cytotoxic potencies, and three CH(2) units were more favorable.