Salicylate Macrolides

Scheme 43 Structure and retrosynthetic analysis of the salicylate macrolides salicylihalamide A (215a) and B (215b) by various groups [103]...

Salicylihalamide A (35) is a salicylic acid-containing macrolide enamide isolated from a sponge Haliclona sp., and it inhibits V-ATPases at a low nM concentration. Members of this family have been isolated from sponges, tunicates, and bac-... 

Porco employed his methodology in the preparation of the salicylate antitumor macrolides lobatamide C [136, 137] and Oximidine II (Scheme 44) [138]. In both cases, re-optimization of the reaction conditions was required, and it was observed that the addition of a stoichiometric amount of diamine ligand (1,10-phenanthroline and DMEDA) was essential for the process to occur. It is noteworthy that when starting from a Z-vinyl iodide (synthesis of oximidine If) the amidation proceeded stereoselectively. Conversely, when starting from a -vinyl iodide (synthesis of lobatamide C) a mixture of enamide isomers was obtained. 

Shen, R., Lin, C.T., and Porco, (.A. (2002) Total synthesis and stereochemical assignment of the salicylate antitumor macrolide lobatamide C from Pacific tunicates. J. Am. Chem. Soc., 124, 5650-5651. 

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