ABSTRACT Knoevenagel condensation of barbituric acids with aromatic aldehydes containing one or two formyl groups was carried out. 5-Arylidenebarbituric acids underwent smooth hetero-Diels-Alder (HDA) reactions with enol ethers to afford cis and trans diastereoisomers of pyrano[2,3-d]pyrimidine-2,4-diones and 5,5'-(1,4-phenylene)bis[2H-pyrano[2,3-d]pyrimidine-2,4(3H)-dione] derivatives in excel...

Introduction: Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) are used in treating pathologic conditions such as fever, pain and inflammation by inhibiting cyclooxygenase and consequently prostaglandin production. Recently , the discovery of different isoforms of this enzyme, Cyclooxygenase-1 (COX-1) andCyclooxygense-2 (COX-2), has led to the synthesis and introduction of novel drugs with select...

re-investigation of the methylene chloride extract of the roots of ferula sinaica gave ferusinol, a new sesquiterpene coumarin with a rare carbon skeleton, and samarcandin diastereomer. the structures elucidation were determined by ms, 1h- 13c-1d and 2d nmr spectral data.

Introduction: Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) are used in treating pathologic conditions such as fever, pain and inflammation by inhibiting cyclooxygenase and consequently prostaglandin production. Recently , the discovery of different isoforms of this enzyme, Cyclooxygenase-1 (COX-1) and Cyclooxygense-2 (COX-2), has led to the synthesis and introduction of novel drugs with selec...

Zinc chlorochromate nonahydrate is easily prepared from the aqueous solution of chromium trioxide and zinc chloride in quantitative yield. This oxidant, in methylene chloride and at room temperature, oxidizes thiols to their disulfides. Acetals and thioacetals are deprotected to their corresponding carbonyl compounds. Sulfides are selectively converted to ther sulfoxides or sulfones. Arylox...

[reaction: see text] A new method to facilitate the separation of diastereomeric syn- and anti-1,3-diols is described. The method relies on the different hydrolysis rates of the corresponding diastereomeric acetonides. Treatment of a dichloromethane solution of syn- and anti-1,3-diol-acetonide with a catalytic amount of diluted aqueous hydrochloric acid leads to the selective cleavage of the an...

A porphyrin functionalised with pillar[5]arene and a viologen at its 5- and 15-meso positions assembles in a head-to-tail manner, producing linear supramolecular daisy chains in dichloromethane. At high concentrations, it forms an organogel which has been investigated by electron microscopy and rheological measurements, paving the way for the preparation of other functional supramolecular assem...

Re-investigation of the methylene chloride extract of the roots of Ferula sinaica gave ferusinol, a new sesquiterpene coumarin with a rare carbon skeleton, and samarcandin diastereomer. The structures elucidation were determined by MS, 1H- 13C-1D and 2D NMR spectral data.

The popular Mattingly [J. Gun. Pathol. 15, 374 (1962)] fluorometric assay for plasma cortisol is shown to give rise to falsely high values when performed with the recommended optical arrangement. By exciting at 470 nm, however, results are obtained that correlate well (r = 0.972) with those of competitive protein binding. The source of the interference is not identified, but it is related to bo...