Eight new diterpenoids from soft coral Cespitularia hypotentaculata

Chemical investigation of the soft coral Cespitularia hypotentaculata resulted in the isolation of eight new diterpenes, cespihypotins E-L (1-8). The new metabolites comprise of six verticillene-type diterpenes, one cespitularane derivative, and one derivative with 14-membered lactone ring. The structures were determined through detailed spectroscopic analyses, especially high resolution ESIMS and 2D NMR techniques. The relative stereochemistry was deduced from NOESY spectrum and application of Mosher's ester technique. Immunomodulatory and antiviral activities of 1-8 were tested and evaluated. The biogenetic pathways for 1-8 were also proposed.     

Cespitulins A-D, novel diterpenoids from Taiwanese Cespitularia taeniata

Four novel diterpenoids, designated cespitulins A-D (1-4) were isolated and characterized from the Taiwanese soft coral Cespitularia taeniata. Their structures were determined by extensive spectroscopic analyses (¹H-¹H COSY, HMQC, HMBC, NOESY). Compounds 1-4 possess an unprecedented bond cleavage between C-9 and C-10 with a hemiacetalic lactone ring rather than a verticillane skeleton.     

New norditerpenoids with trypanocidal activity from Vitex trifolia

Trypanocidal constituents of the fruits of Vitex trifolia were investigated. Activity-guided isolation of the acetone extract resulted in the isolation of two new norditerpene aldehydes, 1 and 2, together with five known diterpenes: vitexifolin E (3), vitexifolin F (4), vitexilactone (5), 6-acetoxy-9-hydroxy-13(14)-labden-16,15-olide (6), and previtexilactone (7). In vitro minimum lethal concentrations of the isolated compounds against epimastigotes of Trypanosoma cruzi were 11 microM (1), 36 microM (2), 34 microM (3), 34 microM (4), 66 microM (5), 66 microM (6), and >265 microM (7).     

Cespitulactams A, B, and C, three new nitrogen-containing diterpenes from Cespitularia taeniata May

Three new nitrogen-containing diterpenoids, designated cespitulactams A (1), B (2), and C (3), were isolated from Cespitularia taeniata May. Compounds 1-3 are novel structures having a phenylethyl amino side at C-10 and with an amide function at C-20. Their structures were determined on the basis of extensive spectroscopic analysis and chemical correlation. The cytotoxicity of 1 and its monoacetate (6) were also evaluated against human cancer cell lines.     

New deterpenes from Spongia officinalis

Four new diterpenes has been isolated from $\text{Spongia}$$\text{officinalis}$ and their structures determined on the basis of spectral and chemical evidence.     

New polyesters from Talaromyces flavus

Six new polyesters, talapolyesters A–F (1–4, 14, and 16), together with 11 known ones 15G256ν (5), 15G256ν-me (6), 15G256π (7), 15G256β-2 (8), 15G256α-2 (9), 15G256α-2-me (10), 15G256ι (11), 15G256β (12), 15G256α (13), 15G256α-1 (15), and 15G256ω (17), were isolated from the wetland soil-derived fungus Talaromyces flavus BYD07-13, and their structures were determined by NMR and MS spectroscopic data. Among them, 1–4 and 16 were assembled in a different manner from that of the known 256 polyesters. All the polyesters are composed of (R)-2,4-dihydroxy-6-(2-hydroxypropyl)benzoic acid and (R)-3-hydroxybutyric acid/(S)-3,4-dihydroxybutyric acid residues. The absolute configurations of the residues were determined by alkaline hydrolysis. The cytotoxicity against five tumor cell lines of these compounds was examined, and a tight structure–activity relationship is proposed.     

New tetrahydroanthraquinones from the genus Cortinarius

Austrocortirubin and austrocortilutein the first hydroxylated tetrahydro-anthraquinones from Basidiomycetes, have been isolated from an Australian toadstool belonging to the subgenus Dermocybe of Cortinarius.     

New sesterterpenes from Madagascan Lendenfeldia sponges

A new furanoterpene designated dehydrofurodendin and nine scalarane sesterterpenes of which four are new, were isolated from two different species of Madagascan sponges of the genus Lendenfeldia, both of which seem to be yet undescribed. The structure of the compounds was elucidated by interpretation of 1D and 2D NMR data. Dehydrofurodendin was found to be a potent inhibitor of HIV-1 RT. Several of the isolated scalaranes exhibited cyctotoxicity against several human tumor cells.     

New xenicane diterpenoids from Xenia florida

Three new xenicane diterpenoids, designated xeniolactones A (1), B (2), and C (3), were isolated from Xenia florida collected in Taiwan. Compound 1 possesses a novel structure having a heterotricyclic skeleton in cyclononane system. The structures of 1-3 were elucidated on the basis of extensive spectroscopic analysis. The cytotoxicity of 1-3 was also evaluated against human cancer cell lines.     

New picrotoxane terpenoids from Picrodendron baccatum

Two new picrotoxane norditerpenoid lactones, picrodendrins X (1) and Y (2), and four new picrotoxane sesquiterpenoid lactones, picrodendrins Z (3), α (4), β (5) and picrodendrioside A (6) were isolated from the bark and leaves of Picrodendron baccatum. Their structures were determined by spectral analysis and X-ray crystallographic analysis.     

New iodotyramine derivatives from Didemnum rubeum

The study of an aqueous extract from the ascidian Didemnum rubeum permitted the isolation of a previously reported derivative diiodo-tyramine derivative together with six new iodo-tyramine derivatives. Their structures were elucidated by NMR and MS analysis.     

New triterpene peroxides from Pseudolarix kaempferi

The first study of the chemical constituents of the leaves of Pseudolarix kaemferi revealed three new triterpene peroxides, pseudolarolides Q (1), R (2), S (3). The stereochemical structures of these new compounds were elucidated on the basis of spectral and single-crystal X-ray analyses.     

New cytotoxic spongian diterpenes from the sponge Dysidea cf. arenaria

Seven new (1-7) and three known (8-10) spongian-class diterpenes have been isolated from the sponge Dysidea cf. arenaria collected in Okinawa. Compound 6 was also isolated from the nudibranch Chromodoris kuniei. The structures of the new entities were elucidated by spectroscopic analyses. Three of the new spongians (2, 6, and 7) showed cytotoxicity against NBT-T2 rat bladder epithelial cells.     

New dimeric aporphine-benzylisoquinoline alkaloids from Thalictrum faberi

From Thalictrum faberi ten new aporphine-benzylisoquinoline dimers were isolated and the complete structures assigned by spectral methods. Of them, thalifaberine (1), thalifabine (2), thalifarapine (3), thalifabatine (4), thalifasine (5) and dehydrothalifaberine (6) ' constitute a new type of aporphine-benzylisoquinoline dimers. Huangshanine (7), faberonine (8), faberidine (9) and dehydrohuangshanine (10) are fetidine-type alkaloids.     

New premyrsinane-type diterpene polyesters from Euphorbia falcata

Four new premyrsinane-type diterpenes (1-4) were isolated from the methanol extract of the whole, undried plant of Euphorbia falcata. Their structures were determined by a combination of 1D and 2D NMR (COSY, HMBC, HSQC and NOESY) techniques and mass spectral data as di-, tetra-, penta- and hexaesters of diterpene polyols, esterified with acetic, benzoic, propanoic, isobutanoic and n-hexanoic acids. One of the compounds contains a rare hemiacetal moiety. This type of diterpenes was previously detected only in four Euphorbia species (Euphorbia aleppica, Euphorbia decipiens, Euphorbia macroclada and Euphorbia pithyusa subsp. cupani).     

New dibenzocyclooctadiene lignans from the Kadsura ananosma

Fourteen new dibenzocyclooctadiene lignans, ananonins A-N (1-14), together with five known compounds, were isolated from the seeds of Kadsura ananosma. The structures and absolute configurations of 1-14 were established using a combination of MS, NMR, and CD techniques. The biological activity of these compounds was evaluated, and ananonin M (13) showed moderate neuroprotective effects in an in vitro assay.     

New naphthoquinone and monoterpenoid from Plumbago zeylanica

New naphthoquinone 2 and new monoterpenoid 3 were isolated from the stems of Plumbago zeylanica, and their structures were determined on the basis of 2D NMR spectroscopy. Absolute configuration of 3 was established by synthesis of its enantiomer. The new naphthoquinone 2 showed potent inhibitory activity against nuclear factor κB (NF-κB), equivalent to that of parthenolide, a known potent inhibitor of NF-κB.     

New diastereomeric bis-sesquiterpenes from Hainan marine sponges Axinyssa variabilis and Lipastrotethya ana

Three unprecedented diastereoisomeric dimers, cis-dimer A (1), cis-dimer B (2) and trans-dimer C (3), exhibiting a bis-bisabolene skeleton, and a new sesquiterpene, dehydrotheonelline (4), their potential precursor, have been isolated from the South China Sea sponges Axinyssa variabilis and Lipastrotethya ana, along with known related sesquiterpenes. The structure of the novel molecules has been determined by extensive NMR spectral analysis.     

New cytotoxic sesquiterpenes from the red algae Laurencia obtusa and Laurencia microcladia

Three new sesquiterpenes (1-3), along with five known (5-9), were isolated from the organic extract of the red alga Laurencia obtusa, collected from the coastal rocks of Serifos in the Aegean Sea. A new dimeric sesquiterpene of the cyclolaurane-type (4) along with four previously reported (7, 10-12) metabolites, were isolated from the extract of Laurencia microcladia, collected at Chios island in the North Aegean Sea. The structures and the relative stereochemistry of the compounds are proposed on the basis of their spectral data. The cytotoxicity of the isolated metabolites was evaluated against several cell lines including human tumor cell lines.