Hyrtiazepine, an Azepino-indole-Type Alkaloid from the Red Sea Marine Sponge Hyrtios erectus

Abstract

Biological and chemical investigations of the methanolic crude extract of the Red Sea marine sponge Hyrtios erectus led to the isolation of a novel azepino-indole-type alkaloid named hyrtiazepine (2) and 5-hydroxy-1H-indole-3-carboxylic acid methyl ester (3), together with the known metabolites hyrtiosulawesine (1), 5-hydroxyindole-3-carbaldehyde (4), hyrtiosin A (5), and hyrtiosin B (6). Their structures were elucidated on the basis of mass spectrometry and detailed 2D NMR spectroscopic data. Hyrtiosulawesine (1) displayed a significant antiphospholipase A2 activity with an IC50 value of 14 microM in a fluorometric assay using Crotalus adamanteus venom phospholipase A2.

Red Sea Sponges of the Genus Hyrtios as a Source of Symbiotic Fungi with Antimicrobial Activities

“…The Red Sea sponges of the genus Hyrtios have proven to be a rich source of biologically active secondary metabolites Youssef et al,2002;Youssef, 2005;Sauleau et al,2006;Youssef et al,2004). Investigation of several Hyrtios species in our laboratory afforded different classes including alkaloids, sesterterpenes, sesquiterpenes and sterols Youssef et al,2002;Youssef, 2005;Sauleau et al,2006;Youssef et al,2004).…”

“…The compounds displayed a diverse array of bioactivities such as antimycobacterial, cytotoxicity, anti-PLA2, and antimicrobial activity Youssef et al,2002;Youssef, 2005;Sauleau et al,2006;Youssef et al,2004). These results encouraged us to look at the symbiotic fungal biodiversity in the Red Sea sponges Hyrtios erecta Youssef et al,2002) and Hyrtios erectus (Youssef, 2005;Sauleau et al,2006) and evaluate the antimicrobial activities of these fungi as a potential and future source of drug leads. Herein we mixture for PCR amplification contained 5 μL of 10 × reaction buffer with 15 mM MgCl2 (Invitrogen), 2 μL of 2.5 mM dNTPs, 0.5 μL of 10 µM each primer, 4 μL of fungal DNA, 0.3 μL of Taq DNA polymerase (5 U·μL−1, Invitrogen), and 39.7 μL of H 2 O. PCR conditions included an initial denaturation at 94 ºC for 4 min followed by 30 cycles of denaturation at 94 ºC for 50 s, annealing at 51 ºC for 50 s, and elongation at 68 °C for 1 min, with a final elongation at 68 ºC for 10 min.…”

“…Investigation of several Hyrtios species in our laboratory afforded different classes including alkaloids, sesterterpenes, sesquiterpenes and sterols Youssef et al,2002;Youssef, 2005;Sauleau et al,2006;Youssef et al,2004). The compounds displayed a diverse array of bioactivities such as antimycobacterial, cytotoxicity, anti-PLA2, and antimicrobial activity Youssef et al,2002;Youssef, 2005;Sauleau et al,2006;Youssef et al,2004).…”

“…Investigation of several Hyrtios species in our laboratory afforded different classes including alkaloids, sesterterpenes, sesquiterpenes and sterols Youssef et al,2002;Youssef, 2005;Sauleau et al,2006;Youssef et al,2004). The compounds displayed a diverse array of bioactivities such as antimycobacterial, cytotoxicity, anti-PLA2, and antimicrobial activity Youssef et al,2002;Youssef, 2005;Sauleau et al,2006;Youssef et al,2004). These results encouraged us to look at the symbiotic fungal biodiversity in the Red Sea sponges Hyrtios erecta Youssef et al,2002) and Hyrtios erectus (Youssef, 2005;Sauleau et al,2006) and evaluate the antimicrobial activities of these fungi as a potential and future source of drug leads.…”

Hyrtinadines C and D, New Azepinoindole-Type Alkaloids from a Marine Sponge <i>Hyrtios</i> sp.

“…Though the number of natural products possessing a 3,4-fused azepinoindole skeleton was limited, 6,8,[10][11][12][13][14][15][16][17][18] those compounds were attracting great interest as synthetic targets. 19) Therefore, 1 and 2 were the new members of relatively rare class of natural products.…”