Tell el-Murra (North Eastern Nile Delta Survey) : season 2008

The Project aims at carrying out an archeological survey of the northeastern part of the Nile Delta and locating archeological sites from Predynastic and Early Dynastic periods. Sites visited during the first season included Tell Akhdar, Gezira Sangaha, Tell Gezira el-Faras, Tell Ginidba, Tell Abu Umran and Tell el-Murra, which - as the most interesting of these sites - was chosen for further research. It included magnetic prospection and geological core drillings. Most surface pottery material shows affinities to Old Kingdom forms, with some pieces similar to Early Dynastic shapes. The core drillings indicated that surface strata from the Old Kingdom may overlie older occupation layers. Regular (linear) anomalies observed on the magnetic map seem to correspond to remains of mud-brick walls

Tell el-Murra (Northeastern Nile Delta Survey) : season 2010

Much of the work of the Northwestern Nile Delta Survey Project involved research at Tell el-Murra, a site in the northeastern part of the Nile Delta chosen for excavation on the basis of results from the 2008 survey season. Archaeological testing was coupled with magnetic prospection and geological core drillings in an effort to establish site stratigraphy and chronology. An analysis of the assemblage of finds (mainly pottery), confirmed occupation of the northeastern part of the site in the Old Kingdom period, after the southwestern part had already been abandoned. Core drilling results suggested the presence of Predynastic layers below the Protodynastic strata explored in 2010. A continued survey around Tell el-Murra comprised prospection at the sites of Tell Abu el-Halyat, Tell el-Akhdar, Minshat Radwan, Tell Gezira el-Faras, Gezira Sangaha, Mantiqat el-Qalaa and Kafr el-Hadidi. Naqada III pottery was confirmed at the first four of these sites

(E)-2-Meth­oxy-4-(3-oxobut-1-en­yl)phenyl acetate

The title compound, C13H14O4, belongs to the class of α,β-unsaturated ketones, which have potential bactericidal, fungicidal, anti­tumor and anti-inflammatory properties. The C atoms and attached H atoms of the ethenyl part of the title mol­ecule are disordered over two orientations with refined occupancies of 0.583 (7) and 0.417 (3). Mol­ecules are connected by two inter­molecular C—H⋯O inter­actions, forming a dimer with symmetry

2,2′-(3,3′-Dihexyl-2,2′-bithio­phene-5,5′-di­yl)bis­(4,4,5,5-tetra­methyl-1,3,2-dioxaborolane)

In the title mol­ecule, C32H52B2O4S2, the two thio­phene rings are twisted by 67.34 (2)°. In the crystal, weak C—H⋯O hydrogen bonds link mol­ecules related by translation along the a axis into chains

Total Synthesis of (±)-Cis-Trikentrin B via Intermolecular 6,7-Indole Aryne Cycloaddition and Stille Cross-Coupling

From PMC: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.An efficient total synthesis of the annulated indole natural product (±)-cis-trikentrin B was accomplished by means of a regioselectively generated 6,7-indole aryne cycloaddition via selective metal-halogen exchange from a 5,6,7-tribromoindole. The unaffected C-5 bromine was subsequently used for a Stille cross-coupling to install the butenyl side chain and complete the synthesis. This strategy provides rapid access into the trikentrins and the related herbindoles, and represents another application of this methodology to natural products total synthesis. The required 5,6,7-indole aryne precursor was prepared using the Leimgruber-Batcho indole synthesis

Novel synthetic inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity that inhibit tumor cell proliferation and are structurally unrelated to existing statins

Pilot-scale libraries of eight-membered medium ring lactams (MRLs) and related tricyclic compounds (either seven-membered lactams, thiolactams or amines) were screened for their ability to inhibit the catalytic activity of human recombinant 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase in vitro. A dozen of the synthetic compounds mimic the inhibition of purified HMG-CoA reductase activity caused by pravastatin, fluvastatin and sodium salts of lovastatin, mevastatin and simvastatin in this cell-free assay, suggesting direct interaction with the rate-limiting enzyme of cholesterol biosynthesis. Moreover, several MRLs inhibit the metabolic activity of L1210 tumor cells in vitro to a greater degree than fluvastatin, lovastatin, mevastatin and simvastatin, whereas pravastatin is inactive. Although the correlation between the concentration-dependent inhibitions of HMG-CoA reductase activity over 10 min in the cell-free assay and L1210 tumor cell proliferation over 4 days in culture is unclear, some bioactive MRLs elicit interesting combinations of statin-like (IC50: 7.4-8.0 µM) and anti-tumor (IC50: 1.4-2.3 µM) activities. The HMG-CoA reductase-inhibiting activities of pravastatin and an MRL persist in the presence of increasing concentrations of NADPH. But increasing concentrations of HMG-CoA block the HMG-CoA reductase-inhibiting activity of pravastatin without altering that of an MRL, suggesting that MRLs and existing statins may have different mechanisms of enzyme interaction and inhibition. When tested together, suboptimal concentrations of synthetic MRLs and existing statins have additive inhibitory effects on HMG-CoA reductase activity. Preliminary molecular docking studies with MRL-based inhibitors indicate that these ligands fit sterically well into the HMG-CoA reductase statin-binding receptor model and, in contrast to mevastatin, may occupy a narrow channel housing the pyridinium moiety on NADP+

Pseudopterosin synthesis from a chiral cross-conjugated hydrocarbon through a series of cycloadditions

The pseudopterosins are a family of diterpene marine natural products, which, by virtue of their interesting anti-inflammatory and analgesic properties, have attracted the attentions of many synthetic chemists. The most efficient syntheses reported to date are 14 and 20 steps in the longest linear sequence for chiral pool and enantioselective approaches, respectively, and all start with precursors that are easily mapped onto the natural product structure. Here, we describe an unconventional approach in which a chiral cross-conjugated hydrocarbon is used as the starting material for a series of three cycloadditions. Our approach has led to a significant reduction in the step count required to access these interesting natural products (10 steps chiral pool and 11 steps enantioselective). Furthermore it demonstrates that cross-conjugated hydrocarbons, erroneously considered by many to be too unstable and difficult to handle, are viable precursors for natural product synthesis