Pseudoceratonic Acid and Moloka’iamine Derivatives from the Red Sea Verongiid Sponge Pseudoceratina arabica

Abstract

During an investigation of the chemistry of the Red Sea Verongiid sponge Pseudoceratina arabica, we discovered a small molecule, pseudoceratonic acid (1), along with the new moloka’iamine derivatives, ceratinines N (2), O (3), and the previously reported compounds moloka’iamine (4), hydroxymoloka’iamine (5) and ceratinamine (6). The structural assignments of 1–6 were accomplished by interpretation of their NMR and HRESIMS spectral data. Pseudoceratonic acid possesses a dibrominated hydrazine-derived functional group not found in any reported chemical compound. Pseudoceratonic acid selectively inhibited the growth of E. coli and S. aureus, while ceratinine N selectively inhibited C. albicans. Further, ceratinine N showed potent cytotoxic effects against the triple-negative breast cancer, colorectal carcinoma, and human cervical carcinoma cell lines down to 2.1 µM.

Magnificines A and B, Antimicrobial Marine Alkaloids Featuring a Tetrahydrooxazolo[3,2-a]azepine-2,5(3H,6H)-dione Backbone from the Red Sea Sponge Negombata magnifica

“…The evaluation of the antimicrobial activities of 1 - 3 against E. coli , S. aureus and C. albicans were carried out using a disk diffusion assay at 50 µg/disc as reported earlier [ 36 , 37 , 38 ].…”

“…The evaluation of the MIC values of compounds 1 - 3 against E. coli was performed using a macrodilution method as reported before [ 36 , 39 ].…”

Application of Networking Approaches to Assess the Chemical Diversity, Biogeography, and Pharmaceutical Potential of Verongiida Natural Products

“…This represents a comprehensive list of all secondary metabolites isolated from Verongiida sponges within the period from 1960 to May 2020. It is important to note that since May 2020 to August 2021, a further 7 papers have been published concerning secondary metabolites from this order that were not included in this analysis [ 176 , 177 , 178 , 179 , 180 , 181 , 182 ]. A full reference list can be found in Supporting Information S1 .…”

Fusaripyridines A and B; Highly Oxygenated Antimicrobial Alkaloid Dimers Featuring an Unprecedented 1,4-Bis(2-hydroxy-1,2-dihydropyridin-2-yl)butane-2,3-dione Core from the Marine Fungus Fusarium sp. LY019

“…The antimicrobial effects of 1 and 2 against C. albicans, E. coli and S. aureus were carried out at 50 µg/disc as previously reported in a disk diffusion assay [39][40][41][42].…”

“…Determination of the MIC of 1 and 2 against C. albicans, E. coli and S. aureus was performed in a macrodilution assay as described earlier [40,43].…”