Two new sarsolenane diterpenes, dihydrosarsolenone (2), methyl dihydrosarsolenoneate (3), and two new capnosane diterpenes, sarsolilides B (5) and C (6), were isolated together with the known analogue, sarsolilide A (4), from the Hainan soft coral Sarcophyton trocheliophorum Marenzeller. Their structures were elucidated by detailed spectroscopic analysis and by comparison with reported data, leading to a structure revision of sarsolenone (1). The absolute configurations of 2 and 5 were determined by TDDFT ECD calculations, and they could be used as ECD reference compounds in the determination of the absolute configuration of their related derivatives. Compounds 4 and 5 exhibited inhibitory activity in vitro against protein tyrosine phosphatases 1B (PTP1B), representing the first report of PTP1B inhibitory activity for capnosane diterpenes.

Two new limonoids, kihadanin C (1) and 23-methoxydasylactone A (2), together with seven related known ones, 3–9, were isolated from the root bark of the plant Dictamnus dasycarpus. The structures of the new compounds were elucidated on the basis of extensive analyses of their spectroscopic data (1D- and 2D-NMR, MS) and by comparison of their NMR data with those reported in the literature. To the best of our knowledge, 1 presents the first example of A,D-seco limonoid with an unusual 3,4-dihydroxy-2,5-dimethoxytetrahydrofuran moiety as ring E. In the bioassay in vitro, 7 showed moderate antibacterial activity against Staphylococcus aureus, while 8 and 9 displayed neuroprotective activities against H₂O₂-induced injury in SH-SY5Y cells.

The efficient synthesis of (S)-dihydroresorcylide (1a) along with trans-resorcylide dimethyl ether (2b), was achieved in linear 9 steps from commercially available orcinol monohydrate (6) with esterification, carbonylation, and ring-closing metathesis (RCM) as the key steps in the synthetic sequence.

This review covers structural diversity and biological activities of terpenes from soft corals of the genus of Sarcophyton, reported from 1995 to July, 2011. During this period, besides undefined species, 16 species of the genus Sarcophyton, from different geographical areas, had been chemically examined. Two hundred and five terpenes had been isolated from this genus, including eleven sesquiterpenes, 165 diterpenes, 29 biscembranoids, some of which had novel skeletons. They exhibited various biological features, such as antifeedant, anti-inflammatory, antiviral, and antifouling activities.

A varierty of previously unreported compounds, the cagelike hexacyclic schicagenin-type nortriterpenoid 1, three pre-schisanartane-type nortriterpenoids 2–4, seven C₂₉ nortriterpenoids 5–11 possessing an uncommon pentacyclic carbon skeleton characterized by a 5/5/7/7/5 fused-ring motif bearing a C₉ side chain, two highly oxygenated C₂₈ nortriterpenoids 12 and 13 containing an unprecedented 5/5/7 ring nucleus bearing a C₁₅ side chain, and the known C₂₉ nortriterpenoid 14 were isolated from the leaves and stems of the Chinese medicinal plant Schisandra chinensis. The structures of these new metabolites were elucidated by means of detailed spectroscopic analysis. The absolute configurations of 4 and 5 were determined by time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculations, allowing the assignment of the absolute configurations of analogous compounds 1–3 and 6–13.

The absolute configurations of onchidione (1), previously reported from the marine pulmonate Onchidium sp., and the related alcohols onchidiol (2) and 4-epi-onchidiol (3), first described as methanolysis products of 1, were assigned by X-ray diffraction analysis and solid-state time-dependent density functional theory electronic circular dichroism. Alcohol 3 was incorrectly reported as the C-16 epimer of 2.

The quantum-mechanical calculation of chiroptical properties such as electronic circular dichroism (ECD) is an increasingly popular tool for establishing the absolute configuration of organic compounds, including natural products. However, this approach is often limited by conformational flexibility, which can be overcome by considering the solid crystalline state instead of solution. By knowing the solid-state geometry, one may employ it as the input structure for ECD calculations and then comparing this with the ECD spectrum measured on a microcrystalline sample. We report here the application of this solid-state ECD approach to establish the absolute configuration of three natural products, namely ximaolide A, sinulaparvalide A and B; all display pronounced flexibility and belong to two families of compounds with remarkable biological activity. The present configurational assignment may also be extended to several analogues whose absolute configurations have not yet been reported.

Two new cembranoids, yalongenes A (1) and B (2), were isolated from the South China Sea soft coral Sarcophyton trocheliophorumMarenzeller. Their structures were elucidated by detailed spectroscopic analysis (IR, MS, and NMR) and by comparison with a related model compound. Yalongenes 1 and 2 were evaluated for their cytoprotective effects on SH-SY5Y cell injury induced by H₂O₂in vitro, and the result showed that only compound 1 had a significant cytoprotective activity at the concentration of 1 μM.

Integracins A (1) and B (2), potent HIV-1 integrase inhibitors, and 15′-dehydroxy-integracin B (3) were isolated for the first time from Chinese mangrove plant Sonneratia hainanensis. Their absolute configurations were determined by the Mosher's method and specific rotation analysis of alcohols (6 and 7) obtained from integracin A in two steps and by chemical correlation. Integracin A (1) also exhibited significant cytotoxicity against the tumor cell lines HepG2 and NCI-H460 with both 100% inhibitions at 25 µg/ml. Chirality 24:459–462, 2012. © 2012 Wiley Periodicals, Inc.

A new indole alkaloid, streptomycindole (1), and a known related compound, N-phenylacetyl-L-tryptophan (2), have been isolated from Streptomyces sp. DA22, associated with South China Sea sponge Craniella australiensis. Their structures were established on the basis of a combination of mass spectrometry, ¹H- and ¹³C-NMR spectroscopic analyses, and chemical methods.

Two new uncommon epoxy-substituted nitrogenous bisabolene-type sesquiterpenes, 3-formamido-7,8-epoxy-α-bisabolane (4), 3-isocyano-7,8-epoxy-α-bisabolane (5), together with three known related sesquiterpenes, 1–3, were isolated from the Hainan sponge Axinyssa sp. Their structures were determined on the basis of extensive spectroscopic analyses and by comparison of their NMR data with those of structurally related compounds.

Two new uncommon polyunsaturated amino ketones, (6Z,9Z,12Z,15Z)-1-[(2-phenylethyl)amino]octadeca-6,9,12,15-tetraen-3-one (1) and (6Z,9Z,12Z,15Z)-1-(diethylamino)octadeca-6,9,12,15-tetraen-3-one (2), were isolated from the Gangxi sponge Haliclona sp. The structures of new compounds 1 and 2 were determined by detailed analysis of their 1D- and 2D-NMR spectra, and high-resolution mass spectrometry.

Lingshuine (1), a novel sesquiterpene amide, along with three known N-containing compounds, 2–4, have been isolated from the Hainan sponge Axinyssa variabilis. The structure of 1 was elucidated by detailed analysis of the spectroscopic data and by chemical methods. Lingshuine represents the first example of a Passerini product formed during the isolation process.

Two new Daphniphyllum alkaloids, macropodumines J and K (1 and 2, resp.), together with six known structurally related alkaloids, 3–8, were isolated from the bark of Daphniphyllum macropodumMiq. The structures of the new compounds 1 and 2 were elucidated on the basis of a comprehensive analysis of their spectroscopic and chemical data. Macropodumine J (1) contains a CN group which is relatively rare in naturally occurring alkaloids. All isolated compounds were tested for their insecticidal activities against a number of insect species. Daphtenidine C (5) is the most active compound against Plutella xylostella. This is the first report of insecticidal properties of Daphniphyllum alkaloids.

Two new cembrane diterpenes, sinulaparvalides A and B (1 and 2, resp.), which contain an intriguing seven-membered lactone moiety, along with the four known related cembranoids 3–6, were isolated from the Hainan soft coral Sinularia parva. The structures of compounds 1 and 2 were established by spectroscopic methods, mainly on the basis of 2D-NMR techniques, and were confirmed by single-crystal X-ray diffraction analysis. The in vitro cytotoxic activities of these compounds were tested on human colon carcinoma (HCT-116), human promyelocytic leukemia (HL-60), and human lung carcinoma (A-549) tumor cell lines.

Four new cembrane diterpenes, 19-hydroxy-sarcocrassolide (1), 18-deacetyldeepoxy lobolide (2), 13-hydroxy-sinularial A (3) and 16-hydroxy-sinulariol C (4), along with four related known compounds (5–8), were isolated from the Hainan soft coral Lobophytum sp. Their structures, including relative stereochemistry, were elucidated by detailed analyses of spectroscopic data and by comparison with the data reported in literature.

Four new Daphniphyllum alkaloids, namely dehydroxymacropodumine A (1), 4,21-deacetyl-23-demethyl-deoxyyuzurimine (2), 7-oxo-deoxyyuzurimine (3), and 4-acetoxydaphmanidin B (4), together with seven known related alkaloids, were isolated from the bark of Daphniphyllum macropodum Miq. The structures of new compounds 1–4 including relative configurations were elucidated on the basis of detailed spectroscopic data analysis and by comparison with related known compounds. Dehydroxymacropodumine A (1) possesses a rare eleven-membered macrolactone ring representing the second example of this backbone isolated from natural sources.

Two new cembranoid diterpenes, diepoxysarcophytonene (1) and sarconphytonol (2), were isolated from the Hainan soft coral Sarcophyton latum. Their structures including relative stereochemistry were established by 1D and 2D NMR spectroscopic techniques. Compound 1 showed weak inhibitory activity against COX-2 in vitro at the concentration of 10⁻⁵ µmol·L⁻¹ with the inhibitory rate of 55%.

Two new bis-cembranoids, ximaolides F (1) and G (2), were isolated from the Hainan soft coral Sarcophyton tortuosum. The structures and relative configurations of the two new compounds were elucidated by the combination of spectroscopic methods, chemical conversion of ximaolide F (1) into ximaolide G (2), and comparison with related model compounds.

Three new N-containing sesquiterpenes, isofarnesyl formamide (2), 7-formamido-7,8-dihydro-α-bisabolane (3), 4,5-epi-10-isothiocyanatoisodauc-6-ene (4), and a known sesquiterpene, farnesyl formamide (1), were isolated from the Hainan marine sponge Axinyssa sp. The structures of the new compounds were elucidated by detailed analyses of their spectroscopic data and by comparison of their NMR data with those of structurally related compounds.

Six new cembrane diterpenes, lobophytolides A–F (1–6, resp.), along with six known related cembranoids, 7–12, were isolated from the Hainan soft coral Lobophytum sp. Their structures, including their relative configuration, were elucidated by extensive analyses of the spectroscopic data and by comparison with related known compounds.

Four new neoclerodane diterpenoids, 15-epilupulin A (1), 6-O-deacetylajugamarin (2), and ajugadecumbenins A (3) and B (4), were isolated from the whole plants of Ajuga decumbens. Their structures were elucidated on the basis of spectroscopic data and chemical correlations.

Four new highly oxygenated guaiane lactones, 1-epimenverin B (1), menverin F (2), 1-deoxymenverin F (3), and menverin G (4), together with the two known related analogues menverins B (5) and C (6), were isolated from the South China Sea gorgonian Menella sp. Their structures and relative configuration were elucidated by analysis of spectroscopic data and by comparison with those of known related compounds.

Three new thiophene-acetylenes, 7-chloroarctinone-b (1), rhapontiynethiophenes A (2) and B (3), along with arctinone-b (4) were isolated from the MeOH extract of the roots of Rhaponticum uniflorum (L.) DC. The structures of the new compounds were elucidated by detailed spectroscopic data analysis and by comparison with known compounds.

HIV-1 integrase (IN) is composed of three domains, the N-terminal domain (NTD, residues 1–50), the catalytic core domain (CCD, residues 51–212), and the C-terminal domain (CTD, residues 213–288). All the three domains are required for the two known integration reactions. CCD contains the catalytic triad and is believed to bind viral DNA specifically, and CTD binds viral DNA in a nonspecific manner. As no clear evidence has confirmed the involvement of NTD in DNA binding directly, NTD has not been seriously considered and less is known about its function in viral replication. In the current work, using a SPR technology-based assay, the HIV-1 viral DNA was determined to bind directly to NTD with a K_D value of 8.8 μM, suggesting that the process of preintegrated complex formation for HIV-1 IN might involve the direct interaction of NTD with viral DNA in addition to binding of viral DNA to the catalytic core domain and C-terminal domain. Moreover, such viral DNA/IN binding could be inhibited by the marine product hyrtiosal from the marine sponge Hyrtios erectus with an IC₅₀ of 9.60±0.86 μM. Molecular dynamic analysis correlated with a site-directed mutagenesis approach further revealed that such hyrtiosal-induced viral DNA/IN binding inhibition was caused by the fact that hyrtiosal could bind HIV-1 NTD at Ser17, Trp19, and Lys34. As hyrtiosal was recently discovered by us as a protein tyrosine phosphatase 1B (PTP1B) inhibitor,1 this work might also supply multiple-target information for this marine product, and the verified HIV-NTD/HIV-1 IN interaction model could have further implications for new HIV-1 IN inhibitor design and evaluation.