OBJECTIVE The objective of this research was to investigate the chemical composition and antibacterial activities of the fatty acids and essential oil from various parts of Ligularia persica Boiss (L. persica) growing wild in north of Iran. MATERIALS AND METHODS Essential oils were extracted by using Clevenger-type apparatus. Antibacterial activity was tested on two Gram-positive and two Gram...

Bicyclodihydrosiloles were readily prepared from optically active enyne compounds by a radical cascade reaction triggered by tris(trimethylsilyl)silane ((Me3Si)3SiH). The reaction was initiated by the addition of a silyl radical to an α,β-unsaturated ester, forming an α-carbonyl radical that underwent radical cyclization to a terminal alkyne unit. The resulting vinyl radical attacked the silico...

Submit Manuscript | http://medcraveonline.com carbonic acid derivatives is a method frequently used for the synthesis of pyrimidines and 1,3-thiazines [1-7]. Although these methods have been mentioned in the literature for a long time, there are only a few examples of investigation on the mechanism and the stereochemistry of reactions. Based on earlier examinations [5-7] reaction of α,β-unsatur...

In this study, twelve neuraminidase (NA) inhibitory compounds 1-12 were isolated from heartwood of Caesalpinia sappan on the basis of their biological activities against three types of viral NAs. Of isolated homoisoflavonoids, sappanone A (2) showed the most potent NAs inhibitory activities with IC(50) values of 0.7 µM [H1N1], 1.1 µM [H3N2], and 1.0 µM [H9N2], respectively, whereas saturated ho...

Imidazolium-based ionic liquids (ILs) serve both as recyclable reaction media and as precatalysts for the N-heterocyclic carbene-catalyzed conjugate addition of α,β-unsaturated aldehydes to chalcones. The reaction produces a broad scope of 1,6-ketoesters incorporating an anti-diphenyl moiety in high yields and with high stereoselectivity. In recycling experiments, the IL can be reused up to fiv...

Oxacyclic structures such as tetrahydrofuran (THF) rings are commonly found in many bioactive compounds, and this has led to several efforts toward their stereoselective syntheses. However, the process of catalytic asymmetric cycloetherification for their straightforward synthesis has remained a challenge. In this study, we demonstrate a novel asymmetric synthesis method for THF via the catalyt...

This paper describes a novel strategy for the synthesis of 2,3,4-trisubstituted pyridines via organocatalyzed three-component reactions. A variety of pyridine derivatives are synthesized from readily available ketones with α,β-unsaturated aldehydes and ammonium acetate under a mild organocatalyst. This protocol leads to rapid N-annulation through C-C and C-N bond formation in a single operation...

The 1,4-addition of a monofluoromethyl nucleophile to a variety of alpha,beta-unsaturated compounds has been achieved under mild conditions using either phosphines or potassium carbonate at room temperature. alpha-Substituted fluoro(phenylsulfonyl)methane easily undergoes Michael addition to alpha,beta-unsaturated ketones, esters, nitriles, sulfones, as well as propynoates at room temperature t...