Heterocycles and a Sorbicillinoid from the Coral-Derived Fungus .

A detailed chemical study of the culture of a coral-derived fungus resulted in the isolation and identification of four new aromatic heterocycles chrysoquinazolinones A-B (-) and chrysobenzothiazoles A-B (-), along with a new sorbicillinoid 4-carboxylsorbicillin (). Chrysoquinazolinones A-B (-) combine a quinazolinone fragment with a bicyclo[2.2.

Terpenoids from the Soft Coral Collected in the South China Sea.

The chemical investigation of the South China Sea soft coral has resulted in the isolation of seven new terpenoids, including two new meroterpenoids, namely sinudenoids F-G (-), and five new cembranes, namely sinudenoids H-L (-). Their structures and absolute configurations were elucidated based on extensive analyses of spectroscopic data, single-crystal X-ray diffraction, comparison with the literature data, and quantum chemical calculations. Among them, sinudenoid F () and sinudenoid G () are rare meroterpenoids featuring a methyl benzoate core.

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.

Sarcoeleganolides H-K, new anti-thrombotic cembranes from soft coral .

Chemical investigation of soft coral the collected from the South China Sea led to the identification of four new cembranes, namely sarcoeleganolides H-K (-). Their structures and absolute configurations were established by 1D and 2D NMR spectroscopy, quantum chemical calculations of NMR chemical shifts and electronic circular dichroism (ECD) data analysis. Moreover, compound exhibited moderate anti-thrombotic activity in zebrafish.

Seven New Lobane Diterpenoids from the Soft Coral .

Seven new lobane diterpenoids, namely, lobocatalens A-G (-), were isolated from the Xisha soft coral . Their structures, including their absolute configurations, were elucidated via spectroscopic analysis, comparison with the literature data, QM-MNR, and TDDFT-ECD calculations. Among them, lobocatalen A () is a new lobane diterpenoid with an unusual ether linkage between C-14 and C-18.

Terpenoids from the Sponge sp. Collected in the South China Sea.

Sarcotragusolides A-D (-), four new butenolide sesterterpenes featuring a rare methyl-transferred 6/6/6-tricyclic fused ring system with a butyrolactone moiety, and echinohalimane B (), an unprecedented monocyclic diterpenoid featuring a 2,7-ring-opened halimane-type skeleton, were isolated from the sponge sp. A γ-hydroxybutenolide sesterterpene derivative (), a new scalarane sesterterpene (), a new subersin-type diterpenoid (), and two known terpenoids were also isolated and identified. The discovery of sarcotragusolides C and D ( and ) with an unprecedented inversion of configuration implied a distinct biosynthetic pathway.

Sarcoelegans A-H, eight undescribed cembranes with anti-inflammatory and anti-thrombotic activities from the South China Sea soft coral Sarcophyton elegans.

Chemical investigation of the South China Sea soft coral Sarcophyton elegans has led to the isolation of eight undescribed cembranes, namely sarcoelegans A-H. Their structures and absolute configurations were unambiguously established by extensive analyses of spectroscopic data, X-ray diffraction, QM-NMR, and TDDFT-ECD calculations. Sarcoelegan A is composed of the rare tricyclo [11.

Structural Investigation of Aaptourinamine by a Novel Module-Assembly-Based Calculation.

Natural products have various and complicated structures, which is still a challenge for elucidating these compounds, especially for those lacking two-dimensional nuclear magnetic resonance (2D NMR) correlations mainly caused by high C/H ratios or proton-deficient and multiple heteroatoms through the conventional structural analytical methods. We reported a novel module-assembly calculation method named Dooerafa, which included constructing the meta-structures by a grafting method based on the crucial and the limited 2D NMR correlations, ring-contraction strategy based on mechanic force field and quantum chemical theory, and self-assemble calculation in Python programming for shaping up the structural candidates along with DFT-GIAO calculation. This new method, verified by a known alkaloid spiroreticulatine with the structure determined by X-ray diffraction, was performed for the structural elucidation of aaptourinamine isolated from marine sponge , showing us a brand new scaffold of imidazo [4,5,1-ij]pyrrolo [3,2-f]quinolin-7(8H)-one, which has a biosynthetic relationship with the bioactive and structurally unique aaptamine alkaloid.

Sarcoeleganolides C-G, Five New Cembranes from the South China Sea Soft Coral .

Five new cembranes, named sarcoeleganolides C-G (-), along with three known analogs (-) were isolated from soft coral collected from the Yagong Island, South China Sea. Their structures and absolute configurations were determined by extensive spectroscopic analysis, QM-NMR, and TDDFT-ECD calculations. In addition, compound exhibited better anti-inflammation activity compared to the indomethacin as a positive control in zebrafish at 20 μM.

Subergorgines A-E, five new suberosanone-purine hybrids from the South China Sea gorgonian Subergorgia suberosa.

Five new suberosanone-purine hybrids, namely subergorgines A-E (1-5), were isolated from the South China Sea gorgonian Subergorgia suberosa. Their structures were elucidated on the basis of extensive spectroscopic data and the absolute configurations were clarified by the theoretical ECD calculation. Compounds 1-5 were rare purine alkaloids merged with the same suberosanone moiety via different C (6)-N bridges.

Neopetrosins A-D and Haliclorensin D, Indole--Mannopyranosides and a Diamine Alkaloid Isolated from the South China Sea Marine Sponge .

Four new indole--mannopyranoside alkaloids, neopetrosins A-D (-), together with one new diamine alkaloid, haliclorensin D (), were isolated from the marine sponge collected off Xisha Island in the South China Sea. Their structures and absolute configurations were determined by spectroscopic analysis, single-crystal X-ray diffraction, calculated electronic circular dichroism (ECD), and DP4+ probability analyses. Compounds , , and exhibited in vivo hepatoprotective activity in a zebrafish model at a concentration of 20 μM.

Identification of a Novel Inhibitor of TfR1 from Designed and Synthesized Muriceidine A Derivatives.

The transferrin receptor 1 (TfR1) plays a key role in cellular iron uptake through its interaction with iron-bound Tf. TfR1 is often reported to be overexpressed in malignant cells, and this increase may be associated with poor prognosis in different types of cancer, which makes it an attractive target for antitumor therapy. The marine natural product Muriceidine A is a potent anticancer agent reported in our previous work.

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.

Guaiane sesquiterpenes from the gorgonian collected in the South China Sea.

Echinoflorine (1), a new dimethylamino-substituted guaipyridine alkaloid with a novel γ-lactone-cyclohepta[]pyridine fused skeleton, and three new guaiane sesquiterpene lactones, echinofloranolides A-C (2-4), together with eight known guaiane sesquiterpenes were isolated from the gorgonian collected in the South China Sea. Their structures were elucidated by 1D and 2D NMR, HRESIMS, calculated ECD and DP4+ probability analyses.

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.

Dolabellane Diterpenes and Elemane Alkaloids from the Soft Coral Collected in the South China Sea.

Five new dolabellane diterpenes, clavularinlides A-E (-), and four new racemic elemane alkaloids, clavulacylides A-D (-), together with one known compound (), were isolated from the soft coral collected in the South China Sea. Their structures were elucidated by 1D and 2D NMR, HRESIMS, calculated ECD, and DP4+ probability analyses. Compounds - showed anti-inflammatory activity in the zebrafish assay.

Lemnalemnanes A-C, Three Rare Rearranged Sesquiterpenoids from the Soft Corals and sp.

Three novel sesquiterpenoids, lemnalemnanes A-C (-), were obtained from marine soft corals and sp. Their structures were determined by 1D/2D NMR spectroscopy, HRESIMS, single-crystal X-ray diffraction analysis (Cu Kα), Mosher's method, and ECD quantum chemistry calculations. Lemnalemnane A () possessed an intriguing basket-like structure with a spiro[bicyclo[3.

Jellynolide A, pokepola esters, and sponalisolides from the aquaculture sponge Spongia officinalis L.

Jellynolide A, an unreported bicyclic diterpenoid with an unprecedented penta-substituted carbon skeleton which implied an irregular biogenic pathway, together with four pairs of rare phosphate triesters, (±)-pokepola ester B-E, one undescribed related racemic furanoterpenoid, (±)-sponalisolide C, one undescribed furanoterpenoid, (-)-sponalisolide D, and two known (±)-sponalisolide B and dendrolasin carboxylic acid were isolated from the aquaculture Spongia officinalis L. Their structures were elucidated by comprehensive spectroscopic analysis, quantum chemical calculation of NMR parameters, and electronic circular dichroism (ECD). The plausible biosynthetic pathway of jellynolide A was proposed.

Two new spongian diterpene derivatives from the aquaculture sponge Linnaeus, 1759.

2,3,19-Triacetoxy-17-hydroxyspongia-13(16),14-diene (), a novel acetoxy diterpenoid, and 18-nor-2,17-hydroxyspongia-1,4,13(16),14-quaien-3-one (), belonging to the rare 18-nor-spongian carbon skeleton, together with six related known metabolites (‒), were isolated from the aquaculture Linnaeus, 1759. Their structures were elucidated by comprehensive spectroscopic analysis, quantum chemical calculation of NMR parameters, and electronic circular dichroism (ECD). Compounds , , and exhibited moderate inhibition against STAT3/NF-B, HIF-1, Wnt signalling pathways.

Penitol A and Penicitols E-I: Citrinin Derivatives from and the Structure Revision of Previously Proposed Analogues.

Penitol A (), a new citrinin derivative with a rare tricyclic spiro skeleton, was isolated from a coral-derived strain of the fungus . In addition, penicitols E-I (-), five new citrinin analogues, were coisolated. Their structures were determined by an analysis of 1D/2D NMR and HRESIMS data, statistical DP4+ analyses based on DFT-GIAO NMR calculations, quantum chemistry ECD calculations, and a single-crystal X-ray diffraction study.

Cytotoxic Manoalide-Type Sesterterpenes from the Sponge Collected in the South China Sea.

Thirteen new linear terpenes, including 11 rare acyclic manoalide derivatives (-), one polyprenylphenol derivative (), and one polyprenylbenzaldehyde derivative (), together with three known compounds (-) were isolated from the sponge collected in the South China Sea. The planar structures were resolved by NMR and MS analyses, while the absolute configurations were fully elucidated by NOESY experiments, combined with experimental and calculated ECD spectra, acetal formation, empirical rules of H and C NMR shifts, DP4+ probability analyses, and Mosher's method. Compounds -, , and demonstrated cytotoxic activities against several human cancer cell lines with IC values ranging from 2 to 10 μM.

Lemnardosinanes A-I: New Bioactive Sesquiterpenoids from Soft Coral sp.

Two rearranged nardosinane sesquiterpenoids with novel carbon skeletons, lemnardosinanes A () and B (), and seven new nardosinane-related sesquiterpeniod lemnardosinanes C-I (), together with a known compound 6,7-seco-13-nornardosinan (), were isolated from the soft coral sp. collected from Xisha Islands of the South China Sea. Their structures were elucidated by comprehensive spectroscopic analyses, Mosher's method, Mo(OAc)-induced circular dichroism experiment, and quantum chemical calculations.

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.