The first total synthesis of (+)-tanzawaic acid B, a natural polyketide bearing a pentadienoic ester and octalin moiety, has been accomplished. The synthetic improvement from previous synthetic conditions facilitated our gram-scale synthesis of the chiral octalin that possesses seven stereogenic centers and that is the core skeleton of almost all of the tanzawaic acid family.
View Article and Find Full Text PDFAn aplyronine A-swinholide A hybrid, consisting of the macrolactone part of aplyronine A and the side chain part of swinholide A, was designed, synthesized, and biologically evaluated. This hybrid induced protein-protein interactions between two major cytoskeletal proteins actin and tubulin in the same manner as aplyronine A, and exhibited potent cytotoxicity and actin-depolymerizing activity. The importance of the methoxy group in the ,,-trimethylserine ester was clarified by the structure-activity relationship studies of the amino acid moiety by using the hybrid analogs.
View Article and Find Full Text PDFAn aplyronine A-swinholide A hybrid, consisting of the macrolactone part of aplyronine A and the side chain part of swinholide A, was designed, synthesized, and evaluated for biological activities. The hybrid retained strong cytotoxicity and actin-depolymerizing activity. In addition, the hybrid induced protein-protein interactions (PPI) between actin and tubulin in the manner of aplyronine A.
View Article and Find Full Text PDFThe synthesis of a novel hydrocarbon, dibarrelane, has been accomplished in 11 steps via an intramolecular REDDA reaction of a masked o-benzoquinone, followed by Clemmensen reduction and Barton decarboxylation. The twisted structure of the tetracyclic dibarrelane skeleton was also clarified via X-ray crystallography. Finally, it was proposed that dibarrelane has C2 symmetry rather than C(2v) symmetry.
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