Isolation and Synthesis of 4-Bromopyrrole-2-carboxyarginine and 4-Bromopyrrole-2-carboxy-N(ε)-lysine from the Marine Sponge Stylissa caribica

Abstract

Two new bromopyrrole alkaloids were isolated from the Caribbean sponge Stylissa caribica. The new natural products, 4-bromopyrrole-2-carboxyarginine (1) and 4-bromopyrrole-2-carboxy-N(epsilon)-lysine (2), are derivatives of amino acids linked with a 4-bromopyrrole-2-carboxylic acid. The structures were elucidated on the basis of NMR and MS/MS data and their absolute configurations assigned via synthesis.

Structural Assignment of Tetrabromostyloguanidine: Does the Relative Configuration of the Palau'amines Need Revision?

“…Approximately 100 members of this alkaloid family are biosynthetically related to oroidin. [3,4] The marine sponge Stylissa caribica [5] was studied by using MS-guided fractionation to afford several new pyrrole-imidazole alkaloids: 4-bromopyrrole-2-carboxy-N(e)-lysine, [6] 4-bromopyrrole-2-carboxyarginine, [6] oxocyclostylidol, [7] and the stylissadines A and B. [8] In the course of this study, a compound with a previously unobserved mass and with a Br 4 Cl isotopic pattern was detected.…”

MS-guided Fractionation as a Fast Way to the Identification of New Natural Products – MALDI-TOF-MS Screening of the Marine Sponge Stylissa caribica

“…The freeze dried sponge samples of Stylissa caribica (94.7 g) were crushed with a mill and extracted at r. t. exhaustively with a 1 : 1 mixture of CH 2 Cl 2 /MeOH [16,17].…”

Strukturaufklärung des Tetrabromstyloguanidins: Muss die relative Konfiguration der Palau'amine revidiert werden?

“…Die ungefähr 100 Verbindungen dieser Strukturklasse leiten sich biosynthetisch vom Oroidin ab. [3,4] Der Schwamm Stylissa caribica [5] wurde in einem Massenspektrometrie(MS)-Screening untersucht, und es konnten mehrere neue Pyrrolimidazol-Alkaloide isoliert werden: 4-Brompyrrol-2-carboxy-N(e)-lysin, [6] 4-Brompyrrol-2-carboxyarginin, [6] Oxocyclostylidol [7] und die Stylissadine A und B.…”

“…[6,7] Der Rohextrakt und die mit Sephadex-LH20-Chromatographie erhaltenen Fraktionen wurden mit HPLC-MS analysiert. Die Sekundärme-tabolite wurden durch RP 18 …”