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Sulfated steroid-amino acid conjugates from the Irish marine sponge Polymastia boletiformis.

ABSTRACT: Antifungal bioactivity-guided fractionation of the organic extract of the sponge Polymastia boletiformis, collected from the west coast of Ireland, led to the isolation of two new sulfated steroid-amino acid conjugates (1 and 2). Extensive 1D and 2D NMR analyses in combination with quantum mechanical calculations of the electronic circular dichroism (ECD) spectra, optical rotation, and 13C chemical shifts were used to establish the chemical structures of 1 and 2. Both compounds exhibited moderate antifungal activity against Cladosporium cucumerinum, while compound 2 was also active against Candida albicans. Marine natural products containing steroidal and amino acid constituents are extremely rare in nature.

SUBMITTER: Smyrniotopoulos V

PROVIDER: S-EPMC4413178 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Sulfated steroid-amino acid conjugates from the Irish marine sponge Polymastia boletiformis.

Smyrniotopoulos Vangelis V Rae Margaret M Soldatou Sylvia S Ding Yuanqing Y Wolff Carsten W CW McCormack Grace G Coleman Christina M CM Ferreira Daneel D Tasdemir Deniz D

Marine drugs 20150324 4

Antifungal bioactivity-guided fractionation of the organic extract of the sponge Polymastia boletiformis, collected from the west coast of Ireland, led to the isolation of two new sulfated steroid-amino acid conjugates (1 and 2). Extensive 1D and 2D NMR analyses in combination with quantum mechanical calculations of the electronic circular dichroism (ECD) spectra, optical rotation, and 13C chemical shifts were used to establish the chemical structures of 1 and 2. Both compounds exhibited moderat ...[more]

PMID: 25812034

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