Aplicyanins - brominated natural marine products with superbasic character

作者：Kostic Marina D; Divac Vera M; Alzoubi Basam M; Puchta Ralph

来源：Zeitschrift Fur Naturforschung Section B-a Journal of Chemical Sciences, 2016, 71(8): 883-889.

DOI：10.1515/znb-2016-0055

<jats:title>Abstract</jats:title>
<jats:p>By using quantum chemical methods (B3LYP/6-311+G(2df,p)//B3LYP/6-31G(d)), we investigated the structures of aplicyanin A, aplicyanin B, aplicyanin C, aplicyanin D, aplicyanin E, and aplicyanin F along with their protonated structures. The calculated gas phase proton affinities of aplicyanin A, aplicyanin C, and aplicyanin E are around –250 kcal mol<jats:sup>−1</jats:sup> and therefore more than 10 kcal mol<jats:sup>−1</jats:sup> higher as in typical proton sponges such as 1,8-bis(dimethylamino)naphthalene. The compounds aplicyanin B, aplicyanin D, and aplicyanin F show reduced proton affinities of approximately –240 kcal mol<jats:sup>−1</jats:sup> because of the acetyl group being conjugated with the imine N=C moiety. Nucleus-independent chemical shift (NICS) calculations on the same level of theory do not show any peculiarities, and a reasonable correlation between the toxicity of aplicyanins and the gas phase proton affinity is not observed.</jats:p>

• 出版日期2016-8