Recently the nature of the lone pair-lone pair interaction in cyclic and bicyclic peroxides as well as in ozonides has been investigated by means of photoelectron (PE) spectroscopy [1-8]. As anticipated from model calculations on simple peroxides [1, 6, 7], there is a correlation between the torsional angle of the R-O-O-R unit and the splitting of the first two bands [5-8]. To investigate the i...

We have recently reported the discovery of an entirely new category of potent antiviral agents based on novel deoxynucleoside analogues with unusual fluorescent bicyclic furo base moieties. To probe structure-activity relationships and to seek to optimize the properties of the lead compounds, we prepared pyrro analogues of the furo systems. We herein report the synthesis, characterization and a...

A Rh-catalyzed 1,3-acyloxy migration of propargyl ester followed by intramolecular [4+2] cycloaddition of vinylallene and unactivated alkyne was developed. This tandem reaction provides access to bicyclic compounds containing a highly functionalized isotoluene or cyclohexenone structural motif, while only aromatic compounds were observed in related transition metal-catalyzed cycloadditions.

In this report, a new series of fluoroquinolone agents which was derived from levofloxacin was synthesized and evaluated against Gram-positive (Bacillus subtillis, Staphylococcus aureus, Staphylococcus epidermidis and Micrococcus luteus) and Gram-negative (Esherichio coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Serratia marcescens) organisms. The results showed that some of the synth...

INTRODUCTION In recent years, synthesis of combination towards various heterocyclic rings has been interest for the source of lead molecules possesses wide range of pharmacological activities. Most of the compounds having pyrimidine and pyrazolidinone nucleus exhibits pharmacological action. [1-3].A broad spectrum of biological activities like antiinflammatory [4], antibacterial [5], antifungal...

The cycloisomerisation of simple keto-alkynes proceeds at room temperature under the mild conditions of gold catalysis. Bicyclic fused and spiro compounds can be obtained by overall 5-exo and 6-exo carbon-carbon bond-forming cyclisations.

An efficient protocol for the synthesis of eight-membered bicyclic compounds from the cycloisomerization of 1,2,4Z,7-tetraenes has been established. The possible intermediate for this transformation was trapped by its Diels-Alder reaction with N-ethyl maleimide. Thus the reaction may proceed via the sequential processes involving [1,5]-hydrogen migration and electrocyclization.

A methanolic extract of the fruits of AMOMUM TSAO-KO (Zingiberaceae) significantly attenuated nitric oxide production in lipopolysaccharide-simulated BV2 microglia. Two new bicyclic nonanes characterized as 6,7-dihydroxy-indan-4-carbaldehyde ( 1) and 6-hydroxy-indan-4-carbaldehyde ( 2) were isolated with the eleven known compounds 6,7-dihydroxy-3,7-dimethyloct-2-enoic acid ( 3), tsaokoin ( 4), ...

The combination of lithiated alkoxyallenes with carbohydrate-derived nitrones constitutes a flexible entry to highly functionalized enantiopure 1,2-oxazine derivatives. They can be used as precursors for acyclic and cyclic carbohydrate-like products such as amino sugar alcohols, azetidine and pyrrolidine derivatives. The Lewis acid-promoted rearrangement of 1,3-dioxolanyl-substituted 1,2-oxazin...