New Shikimic Acid Derivatives From the Marine-Derived Actinomycete Streptomyces sp. G666 and Their Antimicrobial Activities.

Analysis of an antimicrobial extract from the agar-based culture of the marine-derived actinomycete Streptomyces sp. G666 led to the isolation of three new shikimic acid derivatives, streptomine A-C (1-3), along with five known compounds (4-8). Their structures were established by their spectral data analyses, including MS and NMR.

Cytotoxic Phenolic Compounds from Fruit Glandular Trichomes of .

A new flavonoid, macatanarin D (), together with five known stilbenes (), was isolated from fruit glandular trichomes of . Their structures were elucidated on the basis of spectroscopic methods and through comparison with data reported in the literature. All isolated compounds were evaluated for their cytotoxic activities against KB and MCF-7 cell lines.

Antimicrobial Lavandulylated Flavonoids from a Sponge-Derived sp. G248 in East Vietnam Sea.

Three new lavandulylated flavonoids, (2,2'')-6-lavandulyl-7,4'-dimethoxy-5,2'-dihydroxylflavanone (), (2,2'')-6-lavandulyl-5,7,2',4'-tetrahydroxylflavanone (), and (2'')-5'-lavandulyl-2'-methoxy-2,4,4',6'-tetrahydroxylchalcone (), along with seven known compounds were isolated from culture broth of s sp. G248. Their structures were established by spectroscopic data analysis, including 1D and 2D nuclear magnetic resonance (NMR), and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS).

New 9α-Hydroxy-5α,6α-epoxyhydroxysterols from the Vietnamese Marine Sponge .

Chemical investigation of the methanol extract of the Vietnamese marine sponge led to the isolation of six new 9α-hydroxy-5α,6α-epoxysterols: 5α,6α-epoxycholesta-7,22()-dien-3β,9α-diol (), 5α,6α-epoxycholesta-7,24(28)-dien-3β,9α-diol (), (24)-5α,6α-epoxy-24-ethyl-cholesta-7-en-3β,9α-diol (), 5α,6α-epoxycholesta-7-en-3β,9α-diol (), (24)-5α,6α-epoxyergosta-7,22-dien-3β,9α-diol (), and (24)-5α,6α-epoxy-24-methyl-cholesta-7-en-3β,9α-diol () along with the known 5α-6α-epoxysterols: 5α,6α-epoxystigmasta-7-en-3β-ol (), 5α,6α-epoxystigmasta-7,22-dien-3β-ol (), and 5α,6α-epoxyergosta-7-en-3β-ol (). Their structures and their configurations were established on the basis of high resolution mass spectra and extensive 1D and 2D NMR spectroscopic data and by comparison with the literature. Their cytotoxic activity, evaluated against three human cancer cell lines, MCF-7, Hep-G2 and LU-1, revealed that only compounds and exhibited significant antiproliferative activity and compound showed a selective inhibition towards the MCF-7 human breast cancer cells.

Antifouling 26,27-cyclosterols from the Vietnamese marine sponge Xestospongia testudinaria.

Three new C29 sterols with a cyclopropane ring cyclized between C-26 and C-27 of the side chain, aragusterol I (1), 21-O-octadecanoyl-xestokerol A (4), and 7β-hydroxypetrosterol (5b), were isolated from the Vietnamese marine sponge Xestospongia testudinaria, along with the known compounds, aragusterol B (2), xestokerol A (3), 7α-hydroxypetrosterol (5a), 7-oxopetrosterol (6), and petrosterol (7). The structures of the new compounds were established by analysis of spectroscopic data including 1D and 2D NMR, and high-resolution electrospray ionization mass spectrometry (HRESIMS). Their capacity to inhibit the adhesion of isolated bacteria from marine biofilms was evaluated against the bacterial strains Pseudoalteromonas sp.