2,2,2-Trichloro-1-aryl-ethanones can be reduced by RMgX to the corresponding 2,2-dichloro-1-arylethen-1-olates and trapped with a range of electrophiles resulting in either reduction, reduction/aldol, reduction/Claisen condensation or reduction/aldol-Tishchenko products. In addition we demonstrate that 2,2-dichloro-1-arylethen-1-olates undergo counter-ion controlled Darzens condensations, which...

The total synthesis of lundurines A-C has been accomplished in racemic and enantiopure forms in 11-13 and 12-14 steps, respectively, without protection/deprotection of functional groups, by a novel tandem double condensation/Claisen rearrangement, a gold(I)-catalyzed alkyne hydroarylation, a cyclopropanation via formal [3 + 2] cycloaddition/nitrogen extrusion, and a remarkable olefin migration ...

Two different strategies leading to formal total syntheses of platencin are described. The first strategy involving Claisen rearrangement and radical cyclization provides a rapid access to the core structure of platencin, and also use minimum protective-group operations. The second strategy, a protecting group-free route, utilizes a 6-exo-trig radical cyclization and aldol condensation as key s...

The title compounds, C15H12Br2OS2, (I), and C20H15BrOS, (II), were synthesized by employing Claisen-Schmidt condensation of pentan-3-one and di-benzyl-acetone with 5-bromo-thio-phene-2-carbaldehyde in the presence of methano-lic KOH. Even though 1:2 products were expected in both of the reactions, 1:2 and 1:1 products were obtained as (I) and (II), respectively. In (I), the two methyl groups ar...

Bacterial contamination in blood product was still a problem Indonesia. Various studies to improve the safety of by inhibiting bacterial growth developed. Chalcone, is one natural compounds that has ability inhibit growth, so it can be possible use compound for anti-bacterial future. This study aim evaluate activity novel synthesis chalcone (E)-1-(4-hydroxyphenyl)-3-phenylprop-2-en-1-one agains...

We describe here a Tf₂NH-catalyzed formal (3+3) cycloaddition of silyl enol ethers with acrylates as a new domino reaction. In the domino sequence, the catalyst activates Michael addition, deprotonation of the resulting silyloxonium cation and intramolecular Claisen condensation. It was found that reaction modes significantly depend on the reaction temperature. We also examined the mechanistic ...

A novel series of nine indolyl pyrazoline pharmacophore were synthesized by the reaction of hydrazine hydrate derivatives with the synthesized chalcones (C4,C5,C6). The chalcones were synthesized by the Claisen Schimdt condensation method. These pyrazoline derivatives were evaluated for anti-inflammatory activity using Carrageenan induced paw oedema method. The activity profile reveals that the...

The α-pyrone moiety is a structural feature found in a huge variety of biologically active metabolites. In recent times new insights into additional biosynthetic mechanisms, yielding in such six-membered unsaturated ester ring residues have been obtained. The purpose of this mini-review is to give a brief overview of α-pyrones and the mechanisms forming the basis of their natural synthesis. Esp...