Mitsunobu with a catalytic twist

Hiroyuki Ishibashi and co-workers at Kanazawa University have reported in ACIE on a Mitsunobu reaction where they use an iron catalyst and oxygen to regenerate the active azo reagent.

ACIE paper

Lysidicin A synthesis from a triple Claisen rearrangement

Hidenori Watanabe and co-workers at the University of Tokyo have reported in Tetrahedron on the synthesis of lysidicin.  The key reaction being a triple Claisen rearrangement that formed three of the aryl carbon bonds from aryl ether linkages.

Tetrahedron paper

Pleurocybellaziridine

First things first:  Merry Christmas!  Happy holidays!

Toshiyuki Kan and co-workers from the University of Shizuoka have published in ACIEE on the evidence of an aziridine containing amino acid in a fungus called Angel’s wing.  They did some detective work because the aziridine containing amino acid dubbed pleurocybellaziridine is not stable enough for observation.  The carboxylic acid was not stable so they derivitized the natural product to the methyl ester form, which was more stable.  They also synthesized the aziridine containing amino acid to confirm the structures through spectral data.  The aziridine was synthesized via Mitsunobu conditions.  Interestingly the carboxylic acid form is more cytotoxic (87 micromolar, strong activity) compared to the methyl ester (233 micromolar, weak activity).  Pleurocybellaziridine damages the oligodendrocytes, which makes up the myelin sheath in the brain.

ACIEE paper

Mitsunobu Reaction in an Sn2 Prime Context

Kazuhiko Sakaguchi and co-workers at Osaka City University have published in Tetrahedron Letters on a Mitsunobu type anti-Sn2 prime reaction.

 

TL paper

Deguelin Synthesis

Nicolas Winssinger and co-workers at CNRS have published on the synthesis of deguelin where they utilized a Mitsunobu reaction to combine a homoallylic alcohol and a phenolic ring.

Chemistry a European Journal paper