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C26H41NO8, orthorhombic, P212121(no. 19), a= 8.24370(10) Å, b= 13.1867(2) Å, c= 22.8490(4) Å, V= 2483.85(6) Å3, Z= 4, Rgt(F) = 0.0357, wRref(F2) = 0.0975, T = 169.99(10) K.

Pegaharines A–G (1–6), six novel β-carboline alkaloids representing three types of skeleton, were isolated from the seeds of Peganum harmala. Compound 1is a peculiar β-carboline alkaloid characterized by the unprecedented carbon skeleton of an azepine–indole system. Compounds 3–6represent the first examples of heterodimers constructed from rare tetracyclic β-carboline and classic tricyclic β-carboline alkaloids. Compounds 1and 2were characterized by X-ray crystallography. Compound 4exhibited strong antiviral activity against HSV-2, with an IC50value of 2.12 ± 0.14 μM.

Five novel quinolizidine-based alkaloids (1–5) were obtained from the seeds of Sophora alopecuroidesL. Compounds 1and 2are the first examples of sparteine-indolizine and matrine-indolizine alkaloids, respectively, whereas 3and 4are epimeric normatrine-julolidine alkaloids with unusual skeletons. The structures of these compounds were determined by spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism analyses. Hypothetical biosynthetic pathways of 1–5were proposed. Compound 2exhibited significant antiviral activity against the hepatitis B virus.

Five new diterpenoid alkaloids, ajacisines A-E (1-5), were isolated from Delphinium ajacis, along with seven known alkaloids (6-12). On the basis of their spectral data (IR, UV, HR-ESI-MS, 1D and 2D NMR) and chemical properties, the structures of compounds 1-12 were identified. All isolated compounds were evaluated for their in vitro antiviral activities against respiratory syncytial virus, and compounds 3-5 and 8 exhibited moderate to weak effects with IC50 values of 75.2 ±1.1, 35.1 ±0.6, 10.1 ±0.3, and 50.2 ±0.5 µM, respectively. [ABSTRACT FROM AUTHOR]

This article raises an improved program of adding Pseudo-Satellite’s pseudo-range measurement and setting best configuration for Pseudo-Satellite in mentioned program on the basis of existing Binary System [1]. Through comparison and analysis of improved Tri-satellite System and existing Binary System, this article proves that it shortens location time and location precision by adding Pseudo-Satellite to Binary Navigation Location System. Finally this conclusion is approved by simulating Mathematical model using software.

Three new diterpenoids, including one clerodane diterpenoid 1and two linear diterpenoids 2and 3, were isolated from the aerial parts of Croton laui, along with four known compounds 4–7. Structural elucidation of the isolates was performed by spectral methods such as 1D and 2D NMR, IR, UV, and HRESIMS. Compound 1exhibited cytotoxic activities against Hela and MCF-7 cells with IC50values of 14.5 and 62.5 µM, respectively.Three new diterpenoids, including one clerodane diterpenoid 1and two linear diterpenoids 2and 3, were isolated from the aerial parts of Croton laui, along with four known compounds 4–7. Structural elucidation of the isolates was performed by spectral methods such as 1D and 2D NMR, IR, UV, and HRESIMS. And compound 1exhibited cytotoxic activities against Hela and MCF-7 cells with IC50values of 14.5 and 62.5 µM, respectively.

Three new eudesmanolides, prostrolides A–C (1–3), along with six known compounds were isolated from the herbs of Wedelia prostrata(Asteraceae). The structures were determined by extensive analysis of their spectroscopic data (IR, UV, HRESIMS, 1D and 2D NMR). The isolated compounds were evaluated for their cytotoxic activity on human hepatocellular carcinoma HepG2 cells. All isolates exhibited cytotoxic activities with IC50values of 4.60 ± 0.17 to 27.23 ± 0.36 µM.Three new eudesmanolides, prostrolides A–C (1–3), along with six known compounds were isolated from the herbs of Wedelia prostrata(Asteraceae). The structures were determined by extensive analysis of their spectroscopic data (IR, UV, HRESIMS, 1D and 2D NMR). The isolated compounds were evaluated for their cytotoxic activity on human hepatocellular carcinoma HepG2 cells. All isolates exhibited cytotoxic activities with IC50values of 4.60 ± 0.17 to 27.23 ± 0.36 µM.

Two new triterpenoids, tomentoids A and B (1and 2), along with five known ones were isolated from the roots of Rhodomyrtus tomentosa. Their structures were elucidated via extensive spectroscopic methods including HR-ESI-MS, UV, IR, and NMR. In addition, compounds 1and 3–7exhibited potent inhibitory effects on three tumor cell lines: BGC823, SGC7901, and SK-MEL-110.

The human nonmuscle myosin heavy chain B gene contains a 30-nucleotide alternative exon, N30, that is included in the mRNA from neural cells but is skipped in all other cells. We have previously identified an intronic distal downstream enhancer (IDDE) region that is required for neural cell-specific inclusion of N30. In this study, we investigated the mechanism by which the IDDE promotes N30 exon usage. In vitrosplicing analysis using neural cell nuclear extracts and two-exon pre-mRNA substrates, which consist of the N30 exon and either the upstream (E5) or downstream (E6) exon, demonstrates that the IDDE activates upstream E5-N30 splicing by facilitating early prespliceosome complex formation. The IDDE has no effect on N30-E6 splicing where the IDDE resides. Inspection of splice site consensus sequences shows that a polypyrimidine (Py) tract preceding N30 is suboptimal for U2AF binding. Optimizing the Py tract completely relieves the requirement for the IDDE in E5-N30 splicingin vitro. In transfected cells, the wild-type minigene transcripts, which consist of three exons, E5, N30, and E6, undergo neural cell-specific and IDDE-dependent alternative splicing of N30. Optimizing the Py tract in minigenes also completely relieves the requirement for the IDDE in N30 inclusion. Furthermore, overexpression of the truncated U2AF65, which contains the arginine and serine dipeptide-rich domain and linker domain, but lacks the RNA binding domain, selectively inhibits the IDDE-mediated N30 inclusion in mRNA from the wild-type minigene in a dominant negative fashion. These results support the hypothesis that the IDDE facilitates the recognition of the 3′ splice site preceding N30 by a network of protein-protein interactions implicated in the recruitment of U2AF to a suboptimal Py tract.

Interactions of heparin with intact human thrombospondin-1 (TSP1) and with two heparin-binding fragments of TSP1 were characterized using chemically modified heparins, a vascular heparan sulfate proteoglycan, and a series of heparin oligosaccharides prepared by partial deaminative cleavage. The avidity of TSP1 binding increased with oligosaccharide size, with plateaus at 4 to 6 and at 8 to 10 monosaccharide units. The dependence on oligosaccharide size for binding to the recombinant amino-terminal heparin-binding domain of TSP1 was the same as that of the intact TSP1 molecule but differed from that of a synthetic heparin-binding peptide from the type 1 repeats, suggesting that the interaction between intact TSP1 and heparin is primarily mediated by the amino-terminal domain. Based on activities of chemically modified heparins, binding to TSP1 depended primarily on 2-N- and 6-O-sulfation of glucosamine and to a lesser degree on 2,3-O-sulfation and the carboxyl residues of the uronic acids. In contrast, all of these modifications were required for binding of heparin to the type 1 repeat peptides. Affinity purification of heparin octasaccharides on immobilized TSP1 type 1 repeat peptides revealed a preference for oligosaccharides containing the disaccharide sequence IdoA(2-OSO3)α1-4-GlcNS(6-OSO3). Binding of these oligosaccharides to the peptide required the Trp residues. These data demonstrate that the heparin-binding specificities of intact TSP1 and peptides from the type 1 repeats overlap with that of basic fibroblast growth factor (FGF2) and are consistent with the ability of these TSP1-derived molecules to inhibit FGF2-stimulated angiogenesis.

Two new sesquiterpenoids, strophanthoids A and B (1and 2), along with seven known cardiac glycosides were isolated from the roots of Strophanthus divaricatus. Their structures were elucidated on the basis of extensive analyses by IR, HR-ESI-MS, NMR, and single-crystal X-ray diffraction. And the new compounds were tested cytotoxic activities on the tumor cells SK-MEL-110 and SK-MEL-28.

A synthetic peptide containing amino acid residues 190–201 of thrombospondin-1 (TSP1) promoted adhesion of MDA-MB-435 breast carcinoma cells when immobilized and inhibited adhesion of the same cells to TSP1 when added in solution. Adhesion to this peptide was enhanced by a β1integrin-activating antibody, Mn2+, and insulin-like growth factor I and was inhibited by an α3β1integrin function-blocking antibody. The soluble peptide inhibited adhesion of cells to the immobilized TSP1 peptide or spreading on intact TSP1 but at the same concentrations did not inhibit attachment or spreading on type IV collagen or fibronectin. Substitution of several residues in the TSP1 peptide with Ala residues abolished or diminished the inhibitory activity of the peptide in solution, but only substitution of Arg-198 completely inactivated the adhesive activity of the immobilized peptide. The essential residues for activity of the peptide as a soluble inhibitor are Asn-196, Val-197, and Arg-198, but flanking residues enhance the inhibitory activity of this core sequence, either by altering the conformation of the active sequence or by interacting with the integrin. This functional sequence is conserved in all known mammalian TSP1 sequences and in TSP1 from Xenopus laevis. The TSP1 peptide also inhibited adhesion of MDA-MB-435 cells to the laminin-1 peptide GD6, which contains a potential integrin-recognition sequence Asn-Leu-Arg and is derived from a similar position in a pentraxin module. Adhesion studies using recombinant TSP1 fragments also localized β1 integrin-dependent adhesion to residues 175–242 of this region, which contain the active sequence.

Summary Thrombospondins are a rapidly growing family of adhesive proteins that have diverse activities to modulate cellular growth, motility, and gene expression. Thrombospondin-1 (TSP) was the first identified member of this family and is the major form of thrombospondin in human platelets. A method is described to prepare TSP from human platelets in biologically active form with minimal degradation or contamination with other platelet proteins.

Phosphoinositide-3 kinase signaling modulates many cellular processes, including cell survival, proliferation, differentiation, and apoptosis. Currently, it is known that the establishment of respiratory syncytial virus infection requires phosphoinositide-3 kinase signaling. However, the regulatory pattern of phosphoinositide-3 kinase signaling or its corresponding molecular mechanism during respiratory syncytial virus entry remains unclear. Here, the involvement of phosphoinositide-3 kinase signaling in respiratory syncytial virus entry was studied.