The first (4 + 1)-annulation of o-quinone methides with α-branched allenoates as C1 synthons has been developed. This operationally simple protocol gives access to highly functionalized dihydrobenzofurans in an unprecedented fashion with excellent diastereoselectivities and high yields.

A DABCO-catalyzed (3 + 3) annulation between 2-(acetoxymethyl)buta-2,3-dienoate and sulfur ylides has been developed, which provides a facile method for the synthesis of 4H-pyrans bearing a vinyl sulfide group.

An expedient asymmetric total synthesis of aspidophytine is reported. A highly convergent strategy involving the sequential annulation of vinyl iodide 5 with indole 6 exploits varying modes of indole reactivity to provide aspidophytine in 23% over six steps from 5.

An efficient method towards synthesis of 1,10-phenanthrolines is described. Through Lewis acid-catalyzed annulation reaction between 3-ethoxycyclobutanones and 8-aminoquinolines, a variety of unsymmetric and symmetric 1,10-phenanthroline derivatives were readily prepared with high regioselectivity at room temperature.

1. By partial acid hydrolysis a specific carbohydrate may be isolated from gum arabic (gum acacia). This carbohydrate is comparable in its precipitating activity for Type II (and Type III) antipneumococcus serum with the bacterial soluble specific substances themselves. 2. On hydrolysis this fraction yields galactose and two or more complex sugar acids, one of which appears to be a disaccharide...

Polysaccharides derived from type-specific Friedländer bacilli cause inhibition of the multiplication of mumps virus in the allantoic sac of the chick embryo. As little as 5 microg. of polysaccharide is effective as an inhibitor. Inhibition of multiplication is obtained when polysaccharide is injected as long as 4 days after inoculation of virus. Chemical studies have shown that the structural ...

The lateral CC-π-extension of perylene diimides ( PDI s) to coronene CDI leads undesired effects such as the decrease absorption and a hypsochromic shift. This could be overcome by BN-annulation s form superior BNCDIs .

Since vancomycin-intermediate Staphylococcus aureus (VISA) was first reported in Japan in 1997, there has been great concern that heterogeneous vancomycin-intermediate S. aureus (hetero-VISA) is the putative precursor of VISA. To investigate the prevalence, clinical significance, and molecular epidemiology of S. aureus with reduced susceptibility to vancomycin, all consecutive isolates of S. au...

INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358 Gametogenesis and fertilization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358 Inheritance of scutellum color. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

Catalytic direct (hetero)arylation of (hetero)arenes is an attractive alternative to traditional Kumada, Stille, Negishi and Suzuki-Miyaura cross-coupling reactions, notably as it avoids the prior preparation and isolation of (hetero)arylmetals. Developments of this methodology in the oxazole series are reviewed in this article. Methodologies, selectivity, mechanism and future aspects are prese...