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Three new acenaphthene derivatives cis-3-(4'-methoxyphenyl)-acenaphthene-1, 2-diol (1), trans-(1S, 2S)-3-phenyl-acenaphthene-1, 2-diol (2) and 8-(4-hydroxyphenyl)-2H-acenaphthylen-1-one (3) in company with six known compounds were isolated from the 70% ethanol extract of the rhizomes of Musa basjoo. Those chemical constituents were separated and purified by macroreticular resin, silica gel, Toyopearl HW-40F, SephadexLH-20 and other chromatographic methods, respectively. The chemical structures of new compounds were elucidated by HR-ESI-MS, 1 H NMR, 13 C NMR, HMQC, HMBC spectrum and specific optical rotations. Compound 4 was isolated for the first time from the plants of Musa. and compound 7 was firstly assigned the carbon spectrum. Furthermore, the cytotoxic activity of compounds 1-9 against WM9, MDA-MB231, HeLa, K562, DU145, and PC3 were screened with cisplatin as a positive control. Compound 9 showed promising cytotoxic activities with IC 50 values of 2.65±0.38 µM against the HeLa cell lines, while compound 8 possessed significant cytotoxicity with IC 50 values of 6.51±0.44, 18.54±0.68, and 7.98±1.44 µM against the HeLa, MDA-MB231, and WM9 cell lines, respectively.

The title compound was prepared as part of an effort to accomplish the first synthesis of a cis-10b,10c-dimethyl10b,10c-dihydropyrene according to our ''tethered metacyclophane'' strategy. The 11-step synthesis starting from 2,4,6-trimethylphenol had an overall yield of 4.1%. An X-ray crys-The 10b,10c-dihydropyrene skeleton has attracted a great deal of theoretical and experimental interest due to the aromatic character of its 14 π-electron periphery.[1] Since the parent system 1 is prone to the loss of hydrogen to give pyrene, [2] most of the work in this area has been conducted on analogues that bear substituents at the internal (10b and 10c) positions. By far the most prominent of these are the 10b,10c-dimethyl-10b,10c-dihydropyrenes (DMDHPs) 2.DMDHPs are normally prepared by the valence isomerization of the corresponding [2.2]metacyclophanedienes 3 (Scheme 1), which exhibit syn/anti conformational isomerism. Since the valence isomerization is stereospecific, the anti-[2.2]metacyclophanedienes become trans-DMDHPs and the syn-[2.2]metacyclophanedienes are transformed into cis-DMDHPs. The ''cyclophane route'' [3] that is generally used for the synthesis of the [2.2]metacyclophanedienes leads predominantly to the formation of anti conformers and hence trans-DMDHPs. As a result, cis-DMDHPs are not easily accessible compounds and they are not well studied experimentally.We recently demonstrated how the presence of a third bridge (a tether) during the synthesis of the [2.2]metacyclophanediene system could ensure the formation and maintenance of only the syn conformation and thus lead exclusively to the cis isomer of the DMDHP. [4] cis-Dimethyldihydropyrenophane 4 was prepared by this strategy and its Xray crystal structure was determined, thus providing the first experimentally derived structural data for the cis-DMDHP skeleton. 243 tal structure determination revealed a bowl-shaped structure and an almost fully eclipsed central ethano unit; AM1 calculations predict the heat of formation of this compound to be 9.7 kcal mol −1 higher than that of its trans isomer. Scheme 1. The [2.2]metacyclophanedieneϪ10b,10c-dihydropyrene equilibriumThe ultimate goal of this work is to develop a general strategy for the synthesis of cis-DMDHPs 6 (Scheme 2). In order to accomplish this, ways of efficiently excising the tethers from cis-dimethyldihydropyrenophanes 5 or their valence isomeric syn-[2.2]metacyclophanedienes 7 must be developed. In order to do this, the tether will have to contain functionality that is robust enough to survive the synthetic pathway, but nevertheless be susceptible to some sort of cleavage reaction that will not affect the cis-DMDHP system. Thus the oxygen atoms in 4 were included not only for the sake of synthetic simplicity, but (more importantly) also to allow removal of the tether once it has served its purpose of controlling the stereochemistry. The full ''tethered metacyclophane'' strategy is outlined in Scheme 2 and we now report the results of our initial attempts at its implementation in whole.Fo...

A new arylnaphthalide lignan, corniculin (1), was isolated from 75% EtOH extract of Oxalis corniculata. Its chemical structure was determined by mass spectrometric analysis as well as 1D and 2D nuclear magnetic resonance (NMR).

Protosappanoside D (PTD) is a new component isolated from the extract of Caesalpinia decapetala for the first time. Its structure was identified as protosappanin B-3-O-β-D-glucoside by 1H-NMR, 13C-NMR, 2D-NMR and MS techniques. To date, the pharmacological activities, metabolism or pharmacokinetics of PTD has not been reported. Therefore, this research to study the anti-inflammatory activity of PTD was investigated via the LPS-induced RAW264.7 cells model. At the same time, we also used the UHPLC/Q Exactive Plus MS and UPLC-MS/MS methods to study the metabolites and pharmacokinetics of PTD, to calculate its bioavailability for the first time. The results showed that PTD could downregulate secretion of the pro-inflammatory cytokines. In the metabolic study, four metabolites were identified, and the primary degradative pathways in vivo involved the desaturation, oxidation, methylation, alkylation, dehydration, degradation and desugarization. In the pharmacokinetic study, PTD and its main metabolite protosappanin B (PTB) were measured after oral and intravenous administration. After oral administration of PTD, its Tmax was 0.49 h, t1/2z and MRT(0-t) were 3.47 ± 0.78 h and 3.06 ± 0.63 h, respectively. It shows that PTD was quickly absorbed into plasma and it may be eliminated quickly in the body, and its bioavailability is about 0.65%.

Three new compounds, including two new sesquiterpenes (1–2), named Annuumine E−F, and one new natural product, 3‐hydroxy‐2,6‐dimethylbenzenemethanol (3), together with seventeen known compounds (4–20) were isolated from the ethanol extract of the roots of Capsicum annuum L. Among them, five compounds (4, 5, 9, 10 and 20) were isolated from this plant for the first time. The structures of new compounds (1–3) were determined via detailed analysis of the IR, HR‐ESI‐MS and 1D and 2D NMR spectra. The anti‐inflammatory activities of the isolated compounds were evaluated by their ability to reduce NO release by LPS‐induced RAW 264.7 cells. Notably, compound 11 exhibited moderate anti‐inflammatory activity (IC50=21.11 μM). Moreover, the antibacterial activities of the isolated compounds were also evaluated.

Two new compounds, rel-(3 S,4a R,10b R)-3-(4′-methoxyphenyl)-8-hydroxy-9-methoxy-4a,5,6,10b-tetrahydro-3 H-naphtho[2,1-b]pyran (1), 7-hydroxy- 2-phenylnaphthalene-1-carboxylic acid ethyl ester (2), were isolated from the 70% ethanol extract of the rhizomes of Musa basjoo. Their structures were determined on the basis of spectroscopic analysis including 1-dimensional (1D), 2D nuclear magnetic resonance and high-resolution electrospray ionization mass spectroscopy.

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