Jerzy Wicha and co-workers at the Polish Academy of Sciences have published on a synthesis of hepemerone G by using Grubbs catalyst to form the seven membered ring.
Posted by naturalproductman on November 28, 2010
Mark Rizzacasa and co-workers at the University of Melbourne have published in Synthesis on a total synthesis of reveromycin A via a hetero-Diels-Alder approach to access the spirocycle.
Posted in Cascade Reactions, Cycloaddition, Diels-Alder, Methodology, Named Reactions, Pericyclic reactions, Polyketides, Total Synthesis | Leave a Comment »
Posted by naturalproductman on November 28, 2010
Tomasz Janecki and co-workers have published in Synlett on a nice way to make subsituted 3-methylidene-chroman-2-ones (ie: exocyclic methylenes) via 1,4-Grignard addition folowed by Wittig.
Posted in Conjugate Additions, Horner-Wadsworth-Emmons, Methodology, Named Reagents | Leave a Comment »
Posted by naturalproductman on November 27, 2010
Takashi Sakai and co-workers at Okayama University in Japan have published in Organic Letters on an organocatalytic reaction that embeds CO2 into epoxides.
Posted in Cascade Reactions, Methodology, Organocatalytic | Leave a Comment »
Posted by naturalproductman on November 26, 2010
Wei-Dong Zhang and co-workers from Shanghai Jiao Tong University have published in Chem Comm on the isolation of neojaponicone A, which had an IC50 value of 4.5 micrograms/mL activity against LPS-induced NO production in RAW264.7 macrophages.
Posted in Sesquiterpenes, Seven-Membered Rings | Leave a Comment »
Posted by naturalproductman on November 26, 2010
Yang Wang and co-workers from Fudan University have published on a very unusual Friedel-Crafts reaction where they used a regular alkane as the electrophilic unit. You’re probably wondering how they did it…well all they did was put the alkyl substituted aromatic group in the presence of an alkene. The alkene would generate a carbocation in the presence of either a Lewis acid (ie: AlCl3) or Bronstead acid (triflic acid) and that carbocation would in turn strip off a hydride from the Friedel-Crafts substrate (from the alkyl substituent of the aromatic ring).
Posted in Cascade Reactions, Friedel-Crafts, Methodology, Named Reactions | Leave a Comment »
Posted by naturalproductman on November 24, 2010
Masahiko Isaka and co-workers from BIOTEC in Thailand have published in the Journal of Natural Products on the isolation of torrubiellone A, which had anti-malarial activity with an IC50 of 8.1 micromolar.
Posted in Alkaloids, Diseases, Malaria | Leave a Comment »
Posted by naturalproductman on November 24, 2010
Stefan France and co-workers at Georgia Institute of Technology have published in Organic Letters on an indium catalyzed homo-Nazarov reaction using a cyclopropyl-vinyl-ketone as the substrate. As a result a six membered ring is formed.
Posted in Electrocyclization, Methodology, Named Reactions, Nazarov cyclization, Pericyclic reactions | Leave a Comment »
Posted by naturalproductman on November 22, 2010
Pascal Wafo and co-workers from France have published in Organic Letters on the isolation of duboscic acid. It had alpha-glucosidase inhibition activity with with an IC50 value of 100 ± 8.1 μM. So you might wonder why alpha-glucosidase inhibition is important – alpha-glucosidase is an enzyme that hydrolyzes disaccharides into monosaccharides so the inhibition of this enzyme should slow down the absorption of glucose in people, which is especially important in diabetic patients.
Posted in Diabetes Type 2, Diseases, Seven-Membered Rings, Triterpenoids | Leave a Comment »