Determination of absolute stereochemistry, total synthesis, and evaluation of peptides from the myxomycete Physarum melleum

The absolute stereochemistry of melleumin A (1) and B (2), novel peptide compounds isolated from the myxomycete Physarum melleum, was determined by synthesis of their segments and by a modified Mosher’s method. Total synthesis of melleumin B (2) was achieved by a stereoselective method, which provided further evidence for all the absolute stereochemistries of melleumin B (2). The Wnt signal inhibitory activities of 2 and its 10R-epimer 19 were evaluated. Compound 19 showed moderate inhibition of Wnt signal transcription, which suggests that melleumin analogues might be useful as Wnt signal inhibitors.

Graphical abstractWe determined the absolute stereochemistry of melleumin A (1) and B (2). Total synthesis of 2 was achieved and the epimer showed moderate inhibition of Wnt signal transcription.Figure optionsDownload full-size imageDownload as PowerPoint slide