[reaction: see text] A diastereoselective tandem Stille-oxa-electrocyclization reaction provides access to the core of the diterpenoid natural product saudin. Additionally, this new reaction sequence was extended to the convergent preparation of related polycyclic pyran systems.

7 A complete answer is given to a problem posed in 1988 by Ortega concerning convergent splittings of 8 symmetric matrices. 9 © 2008 Published by Elsevier Inc. 10 AMS classification: Primary 65F10; Secondary 15A 11

The convergent total synthesis of the marine natural product (+)-bistramide C confirms the a priori assignments of its relative and absolute configurations, which were originally based on the combined application of [alpha]D analysis, NMR, and synthesis.

It is shown that the series derived by Mizrahi, giving the Husimi transform (or covariant symbol) of an operator product, is absolutely convergent for a large class of operators. In particular, the generalized Liouville equation, describing the time evolution of the Husimi function, is absolutely convergent for a large class of Hamiltonians. By contrast, the series derived by Groenewold, giving...

A recent study reveals that the propagation of intercellular calcium signals is closely associated with the generation of convergent extension movements during Xenopus gastrulation. Such signals provide a mechanism whereby large populations of cells can communicate to generate orchestrated cell movements.

A simple, efficient, and high yielding one-pot protocol has been developed for the synthesis of 4H-benzo[b]pyrans scaffolds installing a three-component tandem Knoevenagel-cyclocondensation reaction of an aldehyde, malononitrile and dimedone using guanidinium chloride as polyfunctional organocatalyst under solvent-free conditions in high to excellent yields. Various aromatic aldehydes were util...

Epithelial cells frequently display--in addition to the common apical-basolateral polarity--a polarization within the plane of the epithelium. This is commonly referred to as planar cell polarity (PCP) or tissue polarity. Examples of vertebrate PCP include epithelial patterning in the skin and inner ear, and also the morphogenetic movements of mesenchymal cells during convergent extension at ga...

Cruentaren A, an antifungal benzolactone produced by the myxobacterium Byssovorax cruenta, is highly cytotoxic against various human cancer cell lines and a highly selective inhibitor of mitochondrial F-ATPase. A convergent and efficient synthesis of cruentaren A is reported, based upon a diastereoselective alkylation, a series of stereoselective aldol reactions utilizing Myers' pseudoephedrine...

[structure: see text] A convergent, stereoselective assembly of the C1-C21 (C1'-C21') fragment of SCH 351448, a 28-membered bis-lactone natural product, has been developed. A highly efficient approach to this fragment assembles 75% of the carbon skeleton and all the stereochemical elements present in the natural product. In addition, an interesting boron ligand effect on the diastereoselectivit...

A highly convergent, enantioselective total synthesis of brevetoxin A is reported. The development of a [X+2+X] Horner-Wadsworth-Emmons/cyclodehydration/reductive etherification convergent coupling strategy allowed a unified approach to the synthesis of two advanced tetracyclic fragments from four cyclic ether subunits. The Horner-Wittig coupling of the two tetracyclic fragments provided substr...