Total Synthesis of Myrtucommulone A

Abstract

In a one‐step conversion, commercially available or known compounds are connected to form myrtucommulone A, an anti‐inflammatory and apoptosis‐inducing substance from the common myrtle Myrtus communis (see scheme). This strategy can be used, as well to prepare myrtucommulone libraries.

Synthesis and biological evaluation of novel myrtucommulones and structural analogues that target mPGES-1 and 5-lipoxygenase

“…Therefore, these compounds give rise to very complex 1 H-NMR-and 13 C-NMRspectra [9,21]. Additionally, the situation is complicated by the fact that in constitutionally symmetric natural myrtucommulones and analogues, the synthesis yields a mixture of the racemate and the meso form [21]. However, structure elucidation is straight forward for rigid compounds obtained through cyclization and dehydration to the respective bis pyrane derivatives [21].…”

“…Due to their flexibility, the compounds exist as mixtures of rotamers and/or keto-enol tautomers which only interconvert slowly on the NMR time scale [9]. Therefore, these compounds give rise to very complex 1 H-NMR-and 13 C-NMRspectra [9,21]. Additionally, the situation is complicated by the fact that in constitutionally symmetric natural myrtucommulones and analogues, the synthesis yields a mixture of the racemate and the meso form [21].…”

“…Additionally, the situation is complicated by the fact that in constitutionally symmetric natural myrtucommulones and analogues, the synthesis yields a mixture of the racemate and the meso form [21]. However, structure elucidation is straight forward for rigid compounds obtained through cyclization and dehydration to the respective bis pyrane derivatives [21]. Therefore, every compound was cyclized in refluxing benzene in the presence of ptoluene sulfonic acid according to Scheme 5 [21].…”

“…Our recently published total synthesis of 1, 4 and 7 offered an efficient method for the synthesis of nonprenylated acylphloroglucinols [21]. The synthesis of 1 combines readily available syncarpic acid (15) [22] with isobutyraldehyde (16) and isobutyryl phloroglucinol (17) in two simple steps (Scheme 1).…”

“…However, structure elucidation is straight forward for rigid compounds obtained through cyclization and dehydration to the respective bis pyrane derivatives [21]. Therefore, every compound was cyclized in refluxing benzene in the presence of ptoluene sulfonic acid according to Scheme 5 [21].…”