Recent synthetic studies leading to structural revisions of marine natural products

Abstract

Because of the highly unique structures of marine natural products, there are many examples of structures that were originally proposed based on spectral analyses but later proven incorrect. In many cases, the total syntheses of the originally proposed structures of marine natural products has confirmed their incorrectness and the subsequent total syntheses of the newly proposed structures proved the revised structures. This review will show such cases appearing after 2005 and demonstrate how the true structures were elucidated.

Keywords: marine natural product; stereoselective; structural revision; synthesis.

Figure 1

Proposed and revised structures of palau’amine.

Figure 2

Structures of 14-membered lactone marine natural products.

Figure 3

Proposed and reproposed structures of elatenyne.

Scheme 1

Synthesis of proposed and revised structures of obyanamide.

Scheme 2

Synthesis of proposed and revised amphidinolide W.

Scheme 3

Synthesis of proposed and revised structures of palmerolide A.

Scheme 4

Synthesis of revised dolastatin 19.

Scheme 5

Synthesis of neopeltolide.

Scheme 6

Total synthesis of brevenal.

Scheme 7

Synthesis of proposed structures of a metabolite from Laurencia sp.

Scheme 8

Synthesis of proposed and revised calafianin.

Scheme 9

Synthesis of proposed and revised tridachiahydropyrone.

Scheme 10

Synthesis of proposed structures of 4′-chloroaurone.

Scheme 11

Synthesis of pericosines.