Myriapora truncata

At the time of isolation, 1.41 kilograms of Myriapora truncata yielded only 0.6 milligrams of the equilibrium mixture of myriaporones 3 and 4. Just as the two were inseparable at that time, it was impossible to separate them when formed synthetically. Additionally, myriaporone 3 was the dominant form in both instances. Without working on a particularly large scale, the route discussed led to the formation of 12 milligrams of the natural product. 

Isolated from Myriapora truncata in the western Mediterranean Sea, myriaporones 1-4 are polyketides that have certain structural analogies with tedanolide, a macrolactone isolated from the sponge Tedania ignis (see Chapter 19). 

Kovganko, N.V. and Ananich, S.K. (1989) Synthesis of (22 )-24-ethylcholesta-7,22-dien-3p,5a,6p-triol, a natural trihydroxysteroid from the bryozoan Myriapora truncata. Khim. Prir. Soedin., 664—669 Chem. Abstr., 113, 59676e. 

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