Pentaketide citrinin

Penicillic acid provides an example of a simple tetra-ketide whose aromatic ring is cleaved and cyclized, as shown by experiments with [l,2- C2]-acetate (Fig. 4). On the other hand, the pentaketide citrinin is the result of the cyclization of a linear polyketide chain wherein... 

A series of pentaketides derived from five C2 units is also known. Eugenone (8) (Fig. 5.3) occurs in the essential oil of cloves, Syzygium aromaticum (Myrtaceae). Citrinin (9), a carcinogenic antimicrobial metabolite produced by several... 

Pentaketides are formed from five acetate/malonate units. Commonly compounds of type (3,53) are produced which are further modified as for the tetraketides in ways which include aromatic ring scission. A simple modification is in the formation of isocoumarins [as 3.58)], Citrinin (3.57) is believed to be derived via 3.56) [39]. 

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