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Two New Neo-debromoaplysiatoxins-A Pair of Stereoisomers Exhibiting Potent Kv1.5 Ion Channel Inhibition Activities.

ABSTRACT: A pair of stereoisomers possessing novel structures with 6/6/5 fused-ring systems, neo-debromoaplysiatoxin E (1) and neo-debromoaplysiatoxin F (2), were isolated from the marine cyanobacterium Lyngbya sp. Their structures were elucidated using various spectroscopic techniques including high resolution electrospray ionization mass spectroscopy (HRESIMS) and nuclear magnetic resonance (NMR). The absolute stereochemistry was determined by calculated electronic circular dichroism (ECD) and gauge-independent atomic orbital (GIAO) NMR shift calculation followed by DP4+ analysis. Significantly, this is the first report on aplysiatoxin derivatives with different absolute configurations at C9-C12 (1: 9S, 10R, 11S, 12S; 2: 9R, 10S, 11R, 12R). Compounds 1 and 2 exhibited potent blocking activities against Kv1.5 with IC50 values of 1.22 ± 0.22 ?M and 2.85 ± 0.29 ?M, respectively.

SUBMITTER: Fan TT

PROVIDER: S-EPMC6950415 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Two New Neo-debromoaplysiatoxins-A Pair of Stereoisomers Exhibiting Potent Kv1.5 Ion Channel Inhibition Activities.

Fan Ting-Ting TT Zhang Hui-Hui HH Tang Yang-Hua YH Zhang Fan-Zhong FZ Han Bing-Nan BN

Marine drugs 20191121 12

A pair of stereoisomers possessing novel structures with 6/6/5 fused-ring systems, neo-debromoaplysiatoxin E (1) and neo-debromoaplysiatoxin F (2), were isolated from the marine cyanobacterium Lyngbya sp. Their structures were elucidated using various spectroscopic techniques including high resolution electrospray ionization mass spectroscopy (HRESIMS) and nuclear magnetic resonance (NMR). The absolute stereochemistry was determined by calculated electronic circular dichrois ...[more]

PMID: 31766406

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