0000000001304700
AUTHOR
Harald Gross
(2S,3′S,3a'R,5′R,7a'R)-5′-[(E)-5-(Furan-3-yl)-2-methylpent-1-en-1-yl]-3-hydroxy-3′,4,7′-trimethyl-1′,2′,3′,3a',5′,7a'-hexahydro-5H-spiro[furan-2,4′-inden]-5-one
The title compound, ircinianin, C25H32O4, belongs to the sesterterpene tetronic acid compound family and was isolated from the marine sponge Ircinia wistarii. These chemical scaffolds are pharmacologically relevant, since they represent a new class of glycine receptor modulators. The furan ring makes a dihedral angle of 35.14 (12)° to the 4-hydroxy-3-methylfuran-2(5H)-one ring. The crystal packing is characterized by intermolecular O—H...O hydrogen bonds, which generate [010] chains.
Selective mono-de-O-acetylation of the per-O-acetylated brasilicardin carbohydrate side chain
Abstract Methanol dried over powdered 4 A molecular sieves can be used for a selective mono-de-O-acetylation of the phenolic acetyl group of the per-O-acetyl protected brasilicardin A carbohydrate side chain. This reaction opens a practical procedure for a synthetic access to derivates of the immunosuppressive and cytotoxic natural product brasilicardin A.
(2S,3S)-2-Azaniumyl-4-[(1S,4aS,4bS,6S,7S,8aS,10aS)-6,7-dihydroxy-2,4b,8,8,10a-pentamethyl-1,4,4a,4b,5,6,7,8,8a,9,10,10a-dodecahydrophenanthren-1-yl]-3-methoxybutanoate–methanol–water (1/1/1)
The title compound, which crystallized as a methanol and water solvate, C24H41NO5·CH4O·H2O, was obtained by heterologous expression of the brasilicardin gene cluster in the bacterium Amycolatopsis japonicum. In the crystal, the components are linked by numerous hydrogen bonds, generating a three-dimensional network.
(2S,3S)-2-Azaniumyl-4-[(1S,4aS,4bS,6S,7S,8aS,10aS)-6,7-dihydroxy-2,4b,8,8,10a-pentamethyl-1,4,4a,4b,5,6,7,8,8a,9,10,10a-dodecahydrophenanthren-1-yl]-3-methoxybutanoate–methanol–water (1/1/1)
The title compound, which crystallized as a methanol and water solvate, C24H41NO5·CH4O·H2O, was obtained by heterologous expression of the brasilicardin gene cluster in the bacterium Amycolatopsis japonicum. In the crystal, the components are linked by numerous hydrogen bonds, generating a three-dimensional network.
CCDC 2058115: Experimental Crystal Structure Determination
Related Article: Michael Eitel, Dhafer S. Zinad, Dieter Schollmeyer, Harald Gross, Pierre Koch|2021|Carbohydr.Res.|504|108312|doi:10.1016/j.carres.2021.108312