Total synthesis of the plasmoidal pigment physarorubinic acid, a polyenoyl tetramic acid

Abstract

The total synthesis of physarorubinic acid, a polyenoyltetramic acid plasmoidal pigment from Physarum polycephalum, is described in a series of steps from (E )-3-iodoacrylic acid 6 and employs aminolysis of the pentaene thioester 11 as a key synthetic step. Lacey–Dieckmann cyclisation and subsequent deprotection then affords physarorubinic acid 1 in high yield and purity.

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