Hexylitaconic acid

Conversely, some polyketides such as the chlorocarolides (18-19) and hexylitaconic acid (23) have only been produced in a salt medium [71]. 

Because of its structural simplicity and odd history, one of the more remarkable natural products of microbial origin is hexylitaconic acid from Aspergillus niger... 

Hexylitaconic acid was found later in a culture of an Arthrinium associated with an unidentified sponge in the Bay of Toyama (Japan). This acid is involved in the process of proteolysis by means of the ubiquitin-proteasome system (Tsukamoto et al., 2006). 

The Nobel Prize in Chemistry 2004 was awarded to A. Ciechanover, A. Hershko, and I. Rose for their work on protein degradation by ubiquitin (ubiquitination of proteins). For additional information, see the review of the first two winners (Hershko and Ciechanover, 1998) and the Nobel Conference on the ubiquitin system (Rose, 2005). Enantiomer (+)-hexylitaconic acid was isolated for the first time in the terrestrial species Aspergillus niger, it is a regulator of plant growth (Isogai et al, 1984). 

Isogai, A., Washizu, M., Kondo, K., Murakoshi, S., and Suzuki, A. (1984) Isolation and identification of (-F)-hexylitaconic acid as plant growth regulator. Agric. Biol. Chem., 48, 2607-2609. 

Nakahashi, A., Miura, N., Monde, K., and Tsukamoto, S. (2009) Stereochemical studies of hexylitaconic acid, an inhibitor of p53-HDM2 interaction. Bioorg. Med. Chem. Lett., 19, 3027-3030. 

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