Antineoplastic agents 397: Isolation and structure of sesterstatins 4 and 5 from hyrtios erecta (the republic of maldives)

Indole alkaloid from the Red Sea sponge Hyrtios erectus

“…The CH 2 Cl 2 -soluble residue of the alcoholic extract of the red sea sponge H. erectus was subjected to vacuum-liquid chromatography eluting with CH 2 Cl 2 -MeOH followed by silica gel column chromatography to afford four compounds (6)(7)(8)(9). While the MeOH-soluble residue was subjected to vacuum-liquid chromatography eluting with gradient CH 2 Cl 2 -MeOH followed by silica gel column chromatography and semipreparative HPLC to afford five compounds (1)(2)(3)(4)(5) (Figure 2), showed correlations which identified an indole-3-carbaldehyde structure.…”

“…Spongistatins, the most important metabolites of the genus Hyrtios discovered to date, showed powerful anticancer activity 6,7 , which encouraged an exhaustive recollection of the H. erecta sponge (600 kg wet wt.) for further chemical investigations, which afforded the antineoplastic agents sesterstatins [8][9][10] . In the present study, H. erectus collected from the Red Sea -Egypt was chemically investigated and a series of indole alkaloids were isolated, deoxyhyrtiosine A (1) and indole-3-carbaldehyde (2) isolated for the first time from the genus Hyrtios; in addition to the known indoles; 5-hydroxy-1H-indole-3-carboxylic acid methyl ester (3), 5-hydroxy-1H-indole-3-carbaldehyde (4) and hyrtiosine A (5) were obtained.…”

Scalarane Sesterterpenoids

“…Phyllofolactone D (131) was isolated, accompanied by its homologue phyllofolactone C (132), from the sponge Phyllospongia foliascens collected at the South China Sea [105]. Phyllofolactone B (133) was found in a Pacific specimen of the sponge Phyllospongia foliascens [106], while in another sample of the same sponge was found the corresponding C-12 epimer, 12-epi-phyllofolactone B (134) [107]. This compound was renamed as phyllofolactone G (134) and was also found in another specimen of the sponge Phyllospongia foliascens collected at the South China Sea [100], accompanied by the related C24-epimer phyllofolactone F (134, Me-24 ).…”

Sesterterpenoids with Anticancer Activity

“…Sesterstatins 4 and 5 (Fig 7, Table 1), are new pentacyclic furanosesterterpenes belonging to the scalarane subgroup isolated from the marine black sponge Hyrtios erecta incorporating a benzoperhydrophenanthrene ring system joined to a furan ring [55]. These natural products are epimers at C4.…”

“…These natural products are epimers at C4. Sesterstatins 4 and 5 inhibited in vitro the growth of various cancer cell lines, including murine P338 leukemia and human BXPC-3 pancreas, RPMI-7951 melanoma, U251 central nervous system (CNS), KAT-4 and SW1736 thyroid, NCI-H460 NSCLC, FADU pharynx and DU-145 prostate cancer models with the IC 50 growth inhibitory concentrations ranging between 4–13 and 5–26 µM, respectively [55]. …”