Covering: 1997 to 2010. The angucycline group is the largest group of type II PKS-engineered natural products, rich in biological activities and chemical scaffolds. This stimulated synthetic creativity and biosynthetic inquisitiveness. The synthetic studies used five different strategies, involving Diels-Alder reactions, nucleophilic additions, electrophilic additions, transition-metal mediated cross-couplings and intramolecular cyclizations to generate the angucycline frames. Biosynthetic studies were particularly intriguing when unusual framework rearrangements by post-PKS tailoring oxidoreductases occurred, or when unusual glycosylation reactions were involved in decorating the benz[a]anthracene-derived cores. This review follows our previous reviews, which were published in 1992 and 1997, and covers new angucycline group antibiotics published between 1997 and 2010. However, in contrast to the previous reviews, the main focus of this article is on new synthetic approaches and biosynthetic investigations, most of which were published between 1997 and 2010, but go beyond, e.g. for some biosyntheses all the way back to the 1980s, to provide the necessary context of information.

Scheme 10. Schmalz Synthesis of 3-Substituted Phthalides from 2-Formylketones Scheme 11. Enantioselective Synthesis of Phthalides via Ketone Hydroacylation Scheme 12. Synthesis of 3-Alkylphthalides from Sulfonylmethyl Benzoic Acids Scheme 13. Synthesis of an Isobenzofuranone via Thermolysis of a Bromomethylbenzoate Scheme 14. Kraus Approach to 3-Cyanophthalide Scheme 15. Ohzeki and Mori Synthesis of (−)-3-Butyl-7hydroxyphthalide Scheme 16. Asymmetric Dihydroxylation-Lactonization Route to Phthalides Chemical Reviews Review dx.

GilOII has been unambiguously identified as the key enzyme performing the crucial C-C bond cleavage reaction responsible for the unique rearrangement of a benz[a]anthracene skeleton to the benzo[d]naphthopyranone backbone typical for the gilvocarcin type natural anticancer antibiotics. Further investigations of this enzyme led to the isolation of a hydroxy-oxepinone intermediate which allowed important conclusions regarding the cleavage mechanism.