Isolation, synthesis, and biological activity of biphenyl and m-terphenyl-type compounds from Dictyostelium cellular slime molds

Synthesis of Magnaldehydes B and E and Dictyobiphenyl B by Microwave‐Promoted Cross‐Coupling of Boronophenols

“…Part of this objective is facilitated by the dual role of the allyl substituent, which serves as a phenol protecting group during the three step conversion of 10 into 15 and subsequently as the moiety involved in the Claisen rearrangement to install the allyl group at the 3Ј-position. [44] We suggest an alternative synthesis of dictyobiphenyl B, in which the roles of the nucleophilic and electrophilic coupling partners are reversed. To underline this point, we investigated the application of these cross-coupling conditions to the synthesis of dictyobiphenyl B (20), a metabolite recently isolated from the slime mold Dictyostelium polycephalum by Kikuchi et al [44] These authors also synthesized dictyobiphenyl B and three other newly discovered bi-and terphenyls, because the amount of material from the biological source was insufficient for structural confirmation and biological evaluation.…”

“…To underline this point, we investigated the application of these cross-coupling conditions to the synthesis of dictyobiphenyl B (20), a metabolite recently isolated from the slime mold Dictyostelium polycephalum by Kikuchi et al [44] These authors also synthesized dictyobiphenyl B and three other newly discovered bi-and terphenyls, because the amount of material from the biological source was insufficient for structural confirmation and biological evaluation. Part of this objective is facilitated by the dual role of the allyl substituent, which serves as a phenol protecting group during the three step conversion of 10 into 15 and subsequently as the moiety involved in the Claisen rearrangement to install the allyl group at the 3Ј-position.…”

Natural Products from Social Amoebae

“…Syntheses of all four compounds were carried out by Kikuchi and co‐workers (Scheme ) . The dictyobiphenyl core was constructed by a Suzuki–Miyaura coupling reaction between pinacolatoboronate 33 and aryl bromide 34 .…”

“…(Scheme ), in which a microwave‐promoted, protecting group‐free Suzuki–Miyaura coupling was achieved in aqueous medium. In this instance, the nucleophilic and electrophilic coupling partners were reversed, when compared to the Kikuchi synthesis . Thus, aryl bromide 44 and para ‐hydroxyphenylboronic acid 45 were subjected to a cross coupling reaction.…”

“…Thus, many of the amoebaln atural products isolated so far were discovered through sheer brute force approaches using large-scale cultivation of amoebae. Typical yields of natural products from 100-600g wet fruiting body weight are reported around 0.5-10 mg. [11] To put this in perspective, this can equate to thousands of petri dishes of fruiting bodies. Natural products from the social amoebae have mostly been isolated from multicellular fruiting bodies.…”