Eleven undescribed sesquiterpenoids with multiple skeleton types and cytotoxicity from the South China Sea soft coral Lemnalia sp.

Marine organisms have great potential for medical and bioproducts applications, with corals having been in the spotlight as an important research target for the discovery of new bioactive marine natural products. Eleven undescribed sesquiterpenoids, named lemnalinoids A-K (1-11), and one known sesquiterpenoid (12) were isolated from the South China Sea soft coral Lemnalia sp. The structures and absolute configurations of new compounds were elucidated by extensive analysis of spectroscopic data, single crystal X-ray diffraction, quantum chemical calculations and TDDFT-ECD calculations.

Litoamentenes A-K, eleven undescribed cembranoids with cytotoxicity from the South China Sea soft coral Litophyton amentaceum.

Eleven undescribed cembrane-type diterpenoids, named litoamentenes A-K (1-11), were isolated from the soft coral Litophyton amentaceum collected from the South China Sea. Their structures were elucidated by extensive analysis of spectroscopic data, comparison with the literature data, single crystal X-ray diffraction, quantum chemical calculations and TDDFT-ECD calculations. This is the first systematic investigation of L.

Lemneolemnanes A-D, Four Uncommon Sesquiterpenoids from the Soft Coral sp.

Four undescribed sesquiterpenoids, lemneolemnanes A-D (-), have been isolated from the marine soft coral sp. The absolute configurations of the stereogenic carbons of - were determined by single-crystal X-ray crystallographic analysis. Compounds and are epimers at C-3 and have an unusual skeleton with a formyl group on C-6.

Four bioactive new steroids from the soft coral collected in South China Sea.

Four new polyhydroxylated steroids lobophysterols E-H (-), together with three known compounds (-), were isolated from the soft coral collected at Xisha Island, China. The structures of the new compounds were elucidated by extensive spectroscopic analysis and comparison with NMR data of structurally related compounds reported in the literature. The absolute configuration of - was determined by X-ray diffraction.

Secondary metabolites from marine sponges of the genus : a comprehensive update insight on structural diversity and bioactivity.

As one of the most common marine sponges in tropical and subtropical oceans, the sponges of the genus , have emerged as unique and yet under-investigated pools for discovery of natural products with fabulous molecular diversity and myriad interesting biological activities. The present review highlights the chemical structure and biological activity of 355 compounds that have been isolated and characterized from the members of sponges, over the period of about five decades (from 1971 to November 2021). For a better understanding, these numerous compounds are firstly classified and presented according to their carbon skeleton as well as their biosynthetic origins.

Minor bioactive indoles from kimchi mirror the regioselectivity in indole-3-carbinol oligomerization.

Kimchi is a globally consumed food with diverse health-benefits, but the low-abundance bioactive compounds in kimchi remain largely neglected. Here we show that kimchi contains a family of low-abundance (0.5-1.

Four new polyhydroxylated steroids from the South Sea sponge Plakortis sp.

Four new polyhydroxylated steroids plaksterols A-D (1-4), together with two known related steroids ergost-7,9(11),22-trien-3β,5α,6α-triol (5) and ergosta-6β-methoxy-7,22-diene-3β,5α-diol (6), were isolated from methanol extract of the South China Sea marine sponge Plakortis sp. Their structures were identified by spectroscopic analysis, including NMR, MS, and IR. The cytotoxicity of the polyhydroxylated steroids were evaluated, and compound 6 showed moderate inhibitory activities against K562, HL-60 and BEL-7402 cells.

Biological and Chemical Diversity of Marine Sponge-Derived Microorganisms over the Last Two Decades from 1998 to 2017.

Marine sponges are well known as rich sources of biologically natural products. Growing evidence indicates that sponges harbor a wealth of microorganisms in their bodies, which are likely to be the true producers of bioactive secondary metabolites. In order to promote the study of natural product chemistry and explore the relationship between microorganisms and their sponge hosts, in this review, we give a comprehensive overview of the structures, sources, and activities of the 774 new marine natural products from sponge-derived microorganisms described over the last two decades from 1998 to 2017.

Bicyclo [6.3.0] Undecane Sesquiterpenoids: Structures, Biological Activities, and Syntheses.

Sesquiterpenoids constitute a marvelously varied group of natural products that feature a vast array of molecular architectures. Among them, the unusual bicyclo [6.3.

Terpenoids from the South China Sea soft coral .

A rare sinulariane-type norcembranoid sinulariadiolide B () with a unique cyano group, and a eunicellin-based diterpenoid multifloralin (), along with two known related analogues, sinulariadiolide () and sclerophytin E (), were isolated from the extract of the South China Sea soft coral . Their structures were elucidated on the basis of detailed spectroscopic analysis and by comparison with previously reported data. Compounds and showed potent antifouling activity against barnacle .

Aplysinopsin-type and Bromotyrosine-derived Alkaloids from the South China Sea Sponge Fascaplysinopsis reticulata.

Seven pairs of new oxygenated aplysinopsin-type enantiomers, (+)- and (-)-oxoaplysinopsins A‒G (1‒7), two new bromotyrosine-derived alkaloids, subereamollines C and D (18 and 19), together with ten known compounds (8‒17) were isolated from the Xisha Islands sponge Fascaplysinopsis reticulata. The planar structures were determined by extensive NMR and MS spectroscopic data. Each of the optically pure enantiomers was achieved by chiral HPLC separation.

Isolation and Absolute Configurations of Diversiform C, C and C Terpenoids from the Marine Sponge sp.

Chemical investigation of MeOH extract of a South China Sea sponge sp. yielded 15 terpenoids belonging to three different skeleton-types, including the unusual C -lactone norditerpenoids (⁻), the rare C pyridine meroterpenoid (), and the notable C manoalide-type sesterterpenoids (⁻, ⁻). Compounds ⁻ were initially obtained as enantiomers, and were further separated to be optically pure compounds (, , , , , , , , and ) by chiral HPLC, with a LiAlH₄ reduction aid for .

Metabolites from the Paracel Islands Soft Coral cf. .

Five new oxygenated sesquiterpenes, molestins A⁻D (, ⁻) and -gibberodione (), three new cyclopentenone derivatives, -sinulolides C, D, and F ((+)-⁻(+)-), one new butenolide derivative, -sinulolide H ((+)-), and one new cembranolide, molestin E (), together with 14 known related metabolites (⁻, (⁻)-⁻(⁻)-, (±)-, (⁻)-, ⁻) were isolated from the Paracel Islands soft coral cf. . The structures and absolute configurations were elucidated based on comprehensive spectroscopic analyses, quantum chemical calculations, and comparison with the literature data.

Cytotoxic components from the Xisha sponge .

A new dolabellane diterpenoid, clavirolide H (), together with eleven known compounds, including two dolabellane diterpenoid ( and ), a rare cavernosine-type C -lactone terpenoid (), a diketopiperazine () and seven sterols (-), were isolated from the Xisha sponge . Their structures were elucidated by extensive spectroscopic analysis, and the four types of compounds of the above isolates were reported from the genus for the first time. Selected compounds , - and - were evaluated for cytotoxic activities against K562, HL-60, Hela, HCT-116, A549, L-02 and BEL-7402 cell lines.

Terpenoids from the Soft Coral sp. Collected in Yongxing Island.

Three new sesquiterpenoids (sinuketal (), sinulins A and B ( and )) and two new cembranoids (sinulins C and D ( and )), as well as eight known sesquiterpenoids () and eight known cembranoids (), were isolated from the Xisha soft coral sp. Their structures were elucidated by extensive spectroscopic analysis. Compound possesses an unprecedented isopropyl-branched bicyclo [6.

Cytotoxic and Antiviral Triterpenoids from the Mangrove Plant Sonneratia paracaseolaris.

A chemical investigation was conducted on the aerial parts of the mangrove plant p, yielding five new triterpenoid paracaseolins A-E (-, and ) together with twelve known analogues (-, -). Their structures were established by extensive spectroscopic methods and comparisons their spectroscopic data with those of the known related compounds. The cytotoxicities against P388, HeLa, A549, and K562 tumor cell lines and anti-H1N1 (Influenza A virus) activities for the isolates were evaluated.

Pyrrole Derivatives and Diterpene Alkaloids from the South China Sea Sponge Agelas nakamurai.

Two pairs of new non-brominated racematic pyrrole derivatives, (±)-nakamurine D (1) and (±)-nakamurine E (2), two new diterpene alkaloids, isoagelasine C (16) and isoagelasidine B (21), together with 13 known pyrrole derivatives ((±)-3 - 15), five known diterpene alkaloids (17 - 20, 22) were isolated from the South China Sea sponge Agelas nakamurai. The racemic mixtures, compounds 1 - 4, were resolved into four pairs of enantiomers, (+)-1 and (-)-1, (+)-2 and (-)-2, (+)-3 and (-)-3, and (+)-4 and (-)-4, by chiral HPLC. The structures and absolute configurations were elucidated on the basis of comprehensive spectroscopic analyses, quantum chemical calculations, quantitative measurements of molar rotations, application of van't Hoff's principle of optical superposition, and comparison with the literature data.

Characteristic Steroids from the South China Sea Gorgonian Muricella sibogae and Their Cytotoxicities.

Twenty-four steroid-based natural products, 9,10-secosteroids (1-10), 1,4-dien-3-one steroids (11-19), and 4-en-3-one steroids (20-24), containing varying side-chains, were isolated from the South China Sea gorgonian Muricella sibogae. The structures of one new 9,10-secosteroid, sibogol D (1), and two new 1,4-dien-3-one steroids, sibogols E and F (11 and 12), were elucidated by extensive spectroscopic analyses and by comparison with the literature data. Cytotoxicities for all the isolates were evaluated against four selected tumor cell lines, HL-60, HCT116, K562, and P388.

Imidazole Alkaloids from the South China Sea Sponge Pericharax heteroraphis and Their Cytotoxic and Antiviral Activities.

Marine sponges continue to serve as a rich source of alkaloids possessing interesting biological activities and often exhibiting unique structural frameworks. In the current study, chemical investigation on the marine sponge Pericharax heteroraphis collected from the South China Sea yielded one new imidazole alkaloid named naamidine J (1) along with four known ones (2-5). Their structures were established by extensive spectroscopic methods and comparison of their data with those of the related known compounds.

Two new eunicellin diterpenoids from the South China Sea gorgonian Muricella sibogae and their bioactivities.

A systematic re-study on gorgonian Muricella sibogae from South China Sea yielded 10 eunicellin-based diterpenoids including two new ones, sibogins C and D (1 and 2). Their structures were elucidated by extensive spectroscopic analyses (1D and 2D NMR, IR and MS) and by comparison with data reported in literatures. All the isolates were tested for cytotoxic and antifouling activities.

Cyclopentenone derivatives and polyhydroxylated steroids from the soft coral Sinularia acuta.

Four new polyhydroxylated steroids, 1-4, and the racemic form of cyclopentenone 9, together with four known steroids, 5-8, one known cyclopentenone derivative, 10, and one known butenolide derivative, 11, were isolated from the soft coral Sinularia acuta collected from Weizhou Island of Guangxi Province, P. R. China.

Cycloartane triterpenoids and their glycosides from the rhizomes of Cimicifuga foetida.

A phytochemical study on the rhizomes of Cimicifuga foetida resulted in the isolation of two new cycloartane triterpenoids (1 and 2), eight new cycloartane glycosides (3-10), and six known cycloartane glycoside analogues (11-16). The structures of 1-10 were determined by application of spectroscopic methods, with the absolute configuration of 1 determined by X-ray crystallography. Compounds 1-6, as three pairs of epimers at C-10 and C-24, belong to a seven-membered-ring variant of 9,10-seco-9,19-cycloartane triterpenoids, and glycosides 3-10 were found to be 3-O-β-D-xylopyranosides.

Polyhydroxylated steroids from the South China Sea soft coral Sarcophyton sp. and their cytotoxic and antiviral activities.

Chemical investigation on the soft coral Sarcophyton sp. collected from the South China Sea yielded three new polyhydroxylated steroids, compounds (1-3), together with seven known ones (4-10). Their structures were established by extensive spectroscopic methods and comparison of their data with those of the related known compounds.

Bioassay-guided isolation of neo-clerodane diterpenoids from Scutellaria barbata.

Bioassay-guided isolation of the aerial part of Scutellaria barbata yielded three new neo-clerodane diterpenoids scutebatas P-R (1-3), together with two known ones: scutebata E (4) and scutebarbatine B (5). The chemical structures of the isolated compounds were elucidated by spectroscopic methods (NMR and MS) and by comparison with the spectroscopic data reported in the literature. All compounds except 3 showed weak cytotoxicity with IC50 values ranging from 35.

Cytotoxic tetraprenylated alkaloids from the South China Sea gorgonian Euplexaura robusta.

Nine achiral tetraprenylated alkaloids, including three new compounds, named malonganenones I-K (1-3, resp.), together with six known analogs, 4-9, were isolated from the gorgonian Euplexaura robusta collected from Weizhou Island of Guangxi Province, China. The structures of compounds 1-3 were elucidated by extensive spectral analyses, especially of their 1D- and 2D-NMR data.