Nocardioazines

Robert Capon and co-workers at the University of Queensland have reported in Organic Letters on the isolation of prenylated diketopiperazines.  Nocardioazine A had an IC50 of 59 micromolar against colon cancer cell lines (SW620).

OL paper

Synthesis of Ent-Hyperforin

Masakatsu Shibasaki and co-workers at the University of Tokyo have recently published in ACIEE on the total synthesis of ent-hyperforin, a polyprenylated acylphloroglucinol.  One of the key reactions was an asymmetric Diels-Alder cycloaddition that involved the use of a cationic iron complex using a chiral pybox ligand.

ACIEE paper

Polyprenylated Compounds

Hong-Xi Xu and co-workers from the Hong Kong Jockey Club Institute of Chinese Medicine have recently published in the Journal of Natural Products on the isolation of garcicowin A, a polyprenylated acylphloroglucinol derivative from the twigs of Garcinia cowa.  However, the previously isolated 30-epicambogin had more impressive cytotoxicity properties with an IC50 value of 5.1 micromolar against HT-29 cells – it was more cytotoxic than cisplatin (26.6 micromolar).

JNP paper