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Two types of thiazole derivatives are synthesized through a multistep cascade sequence with Pd-metalated phosphorus-doped porous organic polymers (POPs) as heterogeneous catalysts. The POPs could be used as both ligands and catalyst supports. No obvious aggregation and loss of any catalytic activity of the catalysts were observed after 10 runs of the reaction. More importantly, imidazo[4,5-d]thiazoles, which are a new class of thiazole derivatives, could be obtained through K2CO3-promoted intramolecular cyclization of the synthesized polysubstituted thiazoles. Furthermore, the in vitro anticancer activity of these new compounds were tested with MTT assay, and compound 4bexhibited good antitumor activity toward T-24 and A549 cells with IC50values of 10.3 ± 0.8 and 11.8 ± 0.5 μM, respectively. In addition, the action mechanism of 4bon tumor cells was determined.

A simple and efficient Cu-catalyzed decarboxylative/click reaction for the preparation of 1,4-disubstituted 5-arylselanyl-1,2,3-triazoles from propiolic acids, diselenides, and azides has been developed. The mechanistic study revealed that the intermolecular AAC reaction of an alkynyl selenium intermediate occurred. The resulting multisubstituted 5-seleno-1,2,3-triazoles were tested for in vitro anticancer activity by MTT assay, and compounds 4f, 4h, and 4pshowed potent cancer cell-growth inhibition activities.

Nitidumpeptins A and B (1and 2), two novel cyclic hexapeptides, were isolated from the herb Zanthoxylum nitidumvar. tomentosum. Their planar structures were elucidated based on NMR and MS spectrometric analysis, and the absolute configurations were determined by the Marfey’s method. Structurally, 1is a unique peptide with a backbone bearing a pyrrolidine-2,5-dione unit, which is the first occurrence moiety specifically in a naturally occurring cyclohexapeptide. The total synthesis of 1and 2was achieved by solution-phase in parallel with solid-phase peptide synthesis, and their absolute configurations were further confirmed. The combination of 2with gefitinib exhibited synergistic antiproliferative activity in acquired gefitinib-resistant non-small cell lung cancer cells (HCC827-gef). The underlying mechanism for the antiproliferative activity of 2was in part associated with the suppression of YAP expression in HCC827-gef cells.

Three new germacrane sesquiterpenoid-type alkaloids with an unusual Δ8-7,12-lactam moiety, glechomanamides A–C (1–3), and two pairs of 7,12-hemiketal sesquiterpenoid epimers (4a/b, 5a/b) were isolated from Salvia scapiformis. Their structures were elucidated by spectroscopic methods including HRESIMS, IR, UV, and 1D and 2D NMR and also confirmed by single-crystal X-ray diffraction analysis. The chemical transformation of compounds 1–5in a solution environment was analyzed by 2D NMR spectroscopy. The aza acetallactams (1–3) were stable in organic solvent, while single crystals of the hemiacetal esters (4a/b, 5a/b) underwent a tautomeric equilibrium after being dissolved. Single crystals of 4a, 4b, and 5awere obtained for the first time as their naturally occurring forms. Glechomanamide B (2) exhibited antiangiogenic activity by suppression of vascular endothelial growth factor (VEGF)-induced tube formation through modulation of VEGF receptor 2 (VEGFR2)-mediated signaling pathways in human umbilical vascular endothelial cells (HUVECs). In addition, compound 2also showed the significant suppression of mRNA expression associated with glycolysis and angiogenesis biomarkers in high glucose (30 mM)-induced HUVECs. These findings suggest that compound 2might be a potential lead compound candidate for the management of diabetic retinopathy.

An unexpected cyclization of thioamides with p-quinone methides promoted by acridinium salt under the irradiation of visible light furnished 1,2,4-dithiazoles in moderate to good yields. In addition, the reaction of the obtained 1,2,4-dithiazoles with isocyanides offered a new entry for the synthesis of thiazol-5(4H)-imines in moderate yields.

Ten new clerodane diterpenoid glucosides (1–10) and three known analogues (11–13) were isolated from an EtOAc extract of the stems of Tinospora sinensis. Spectroscopic analyses and chemical methods were used to elucidate the structures of these isolates. The absolute configurations of tinosinenosides A–C (1–3) were established by using experimental and calculated ECD data. Their cytotoxicity against the human epithelioid cervical carcinoma (HeLa) cell line and the nitric oxide production inhibitory activity of lipopolysaccharide-activated N9 microglial cells were tested. 1-Deacetyltinosposide A (12) exhibited mild cytotoxicity against HeLa cells, with an IC50value of 8.35 ± 0.60 μM.

Background: Cancer is one of the most serious clinical problems worldwide, and considerable efforts have been devoted to discovering therapeutic agents with novel modes of action. Natural and synthetic coumarin derivatives have attracted intense research interest due to their diverse structural features and remarkable array of biological properties. Objective: In the present study, we synthesized a series of 4-MU derivatives containing urea-piperazine and thioureapiperazine moieties and evaluated their antitumor activities to find efficacy antitumor drugs. Method: Cell proliferation, apoptosis, cell cycle, the generation of reactive oxygen species and calcium were measured using MTT assay and flow cytometry, respectively. The expression of apoptosis- and proliferation-related proteins was determined by western blotting. The effect of 4l on apoptosis-related mRNA expression in NCI-H460 cells was detected by RT-PCR. Results: Most of the target compounds exhibited potential anticancer activities against tested cancer cells but had low cytotoxicity to normal cells. Compound 4l inhibited the growth and proliferation of NCI-H460 cells and resulted in apoptosis. Successive studies conducted with 4l in NCI-H460 cells demonstrated that this compound induced the intracellular reactive oxygen species generation and calcium overload, suppressed nuclear factor-ΚB (NF-ΚB) activity and regulated anti- and pro-apoptotic proteins. In addition, compound 4l effectively arrested NCI-H460 cells in G2 phase and altered the cell cycle regulatory proteins especially cyclin B1. Conclusion: Compound 4l exerts significant anticancer effects on NCI-H460 cells in vitro through targeting of mitochondria-dependent apoptotic pathway. These results indicate that the strategy for rational design of 4-MU derivatives may identify potential anticancer agents.

Three new matrine-type alkaloids, (+)-5α-hydroxyoxysophocarpine (1), (−)-12β-hydroxyoxysophocarpine (2), and (+)-5α-hydroxylemannine (3), along with 14 known analogues, (−)-sophocarpine (4), (−)-5α-hydroxysophocarpine (5), (−)-9α-hydroxysophocarpine (6), (+)-12α-hydroxysophocarpine (7), (−)-12β-hydroxysophocarpine (8), (+)-oxysophocarpine (9), (+)-matrine (10), (+)-sophoranol (11), (+)-9α-hydroxymatrine (12), (−)-14β-hydroxymatrine (13), (+)-oxymatrine (14), (+)-5α-hydroxyoxymatrine (15), (−)-14β-hydroxyoxymatrine (16), and (+)-sophoramine (17), were isolated from the rhizomes of Sophora tonkinensis. Their structures were elucidated via spectrometric data analyses, and the absolute configurations were established by single-crystal X-ray diffraction and ECD data. Alkaloids 2, 6, 11, and 13exhibited antiviral activity against the Coxsackie virus B3 (CVB3), with IC50values of 26.62–252.18 μM, and alkaloids 7, 8, and 17inhibited influenza virus A/Hanfang/359/95 (H3N2) replication with IC50values of 63.07–242.46 μM.

Chiral alcohols(3, 5) were synthesized in optically pure forms from easily available rosin acid in short-steps. A comprehensive protocol for the enantiomeric excess assays of mono-or di-functional-grouped chiral secondary amine or alcohol has been established with them used as chiral auxiliary for chiral phosphorus derivatizing agents(CPDAs) in 31P NMR tests. Chemical shift difference(ΔδP) values ranging from 4.5 to 0.15 between two diastereoisomers of the CPDAs and the aryl substrates were obtained. Positive ΔδR-Swas observed for all the tested alcohol P(III) and P(V) derivatives, while negative ΔδR-Swas observed for all the amines.

Previous researches on oil price volatility have been done with parametric models of GARCH types. In this work, we model volatility of crude oil price based on GARCH(p,q) by using Neural Network which is one of powerful classes of nonparametric models. The empirical analysis based on crude oil prices in US and China show that the proposed models significantly generate improved forecasting accuracy than the parametric model of normal GARCH(p,q). Among nine different combinations of hybrid models (for p = 1,2,3 and q = 1,2,3), it is found that NN-GARCH(1,1) and NN-GARCH(2,2) perform better than the others in US market whereas, NN-GARCH(1,1) and NN-GARCH(3,1) outperform in Chinese case.

Three new tyramine-type alkamides (1–3), three new natural products (4–6), five new N-acylated/formylated aporphine alkamides with different ratios of rotational isomers (7–11), and 20 known alkamides (12–31) were isolated from an EtOH extract of the stems and leaves of Piper puberulum. The absolute configurations of compounds 7, 8, and 10were determined by single-crystal X-ray diffraction analysis. In the biological activity assay, compounds 3, 5, and 10–23displayed inhibitory effects against lipopolysaccharide-induced NO release in BV-2 microglial cells, exhibiting IC50values of 0.93–45 μM.

Reductive coupling of o-substituted carbonyl compounds and m-substituted carbonyl compounds by the direct transfer of electron to carbonyl group respectively gave 1-(4-(1-hydroxy-1-phenylethyl/methyl)phenyl)ethanones/methanones and 2,3-bis(3-substitutedphenyl)butane/ethane-2,3-diols. 4-Methoxyacetophenone surprisingly gave 4-methoxybenzoic acid as oxidation product. Even acetophenone conjugated with alkyne group afforded interesting reductive addition product. Finally, imine also furnished reductively coupled diamino compound. Probable mechanisms for the formation of products is proposed.

The new, efficient, and widely applicable method to prepare 1,3,5‐substituted benzenes can also be used for the synthesis of some hexasubstituted benzenes.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.