Search

As one of the common malignancies that threaten human life, bladder cancer occurs frequently with a high mortality rate in the world, due to its invasion, recurrence and drug resistance. Natural products from marine microorganisms are becoming the hotspots in discovery of new candidate drug entities, especially in the area of cancer. Brefeldin A (BFA) is a natural Arf-GEFs inhibitor, but due to the low aqueous solubility, strong toxicity, and poor bioavailability, it is urgent to conduct structural optimization research. Herein, a new BFA pyridine acrylate derivative CHNQD-01281with improved solubility was prepared and found to exert moderate to strong antiproliferative activity on a variety of human cancer cell lines. It was noteworthy that CHNQD-01281was most sensitive to two bladder cancer cell lines T24 and J82 (IC50= 0.079 and 0.081 μmol/L) with high selectivity index (SI = 14.68 and 14.32), suggesting a superior safety to BFA. In vivo studies revealed that CHNQD-01281remarkably suppressed tumor growth in a T24 nude mice xenograft model (TGI = 52.63%) and prolonged the survival time (ILS = 68.16%) in an MB49 allogeneic mouse model via inducing infiltration of cytotoxic T cells. Further mechanism exploration indicated that CHNQD-01281regulated both EGFR/PI3K/AKT and EGFR/ERK pathways and mediated the chemotactic effect of chemokines on immune effector cells. Overall, CHNQD-01281may serve as a potential therapeutic agent for bladder cancer through multiple mechanisms.

Non-alcoholic steatohepatitis (NASH) is a primary cause of cirrhosis and hepatocellular carcinoma. Unfortunately, there is no approved drug treatment for NASH. AMP-activated kinase (AMPK) is an important metabolic sensor and whole-body regulator. It has been proposed that AMPK activators could be used for treating metabolic diseases such as obesity, type 2 diabetes and NASH. In this study, we screened a marine natural compound library by monitoring AMPK activity and found a potent AMPK activator, candidusin A (CHNQD-0803). Further studies showed that CHNQD-0803directly binds recombinant AMPK with a KDvalue of 4.728 × 10–8M and activates AMPK at both molecular and intracellular levels. We then investigated the roles and mechanisms of CHNQD-0803in PA-induced fat deposition, LPS-stimulated inflammation, TGF-β-induced fibrosis cell models and the MCD-induced mouse model of NASH. The results showed that CHNQD-0803inhibited the expression of adipogenesis genes and reduced fat deposition, negatively regulated the NF-κB-TNFα inflammatory axis to suppress inflammation, and ameliorated liver injury and fibrosis. These data indicate that CHNQD-0803as an AMPK activator is a novel potential therapeutic candidate for NASH treatment.

Further insights on the secondary metabolites of a soft coral-derived fungus Aspergillus versicolorunder the guidance of MS/MS-based molecular networking led to the isolation of seven known cycloheptapeptides, namely, asperversiamides A–C (1–3) and asperheptatides A–D (4–7) and an unusual pyrroloindoline-containing new cycloheptapeptide, asperpyrroindotide A (8). The structure of 8was elucidated by comprehensive spectroscopic data analysis, and its absolute configuration was determined by advanced Marfey’s method. The semisynthetic transformation of 1into 8was successfully achieved and the reaction conditions were optimized. Additionally, a series of new derivatives (10−19) of asperversiamide A (1) was semi-synthesized and their anti-tubercular activities were evaluated against Mycobacterium tuberculosisH37Ra. The preliminary structure−activity relationships revealed that the serine hydroxy groups and the tryptophan residue are important to the activity.

Background: Chronic Myeloid Leukemia (CML) is a myeloproliferative disease caused by BCR-ABLoncoprotein. Tyrosine kinase inhibitors have been developed to inhibit the activity of BCR-ABL; however, drug resistanceand side effect occur in clinic application. Therefore, it is urgent to find novel drugs for CML treatment. Underthe guidance of cytotoxic activity, crude extracts of 55 fungal strains from the medicinal mangrove Acanthus ilicifoliuswere evaluated, and one potent cytotoxic natural compound, brefeldin A (BFA), was discovered from Penicillium sp.(HS-N-29). Objective: This study was aimed to determine the cytotoxic activity of BFA and the effect on the activation and expressionof BCR-ABL in K562 cells. Methods: We evaluated cytotoxic activity by MTT assay and soft agar clone assay; apoptosis and cell cycle distributionby Muse cell analyzer. The protein level of BCR-ABL and signaling molecules was detected by western blotting,and the mRNA level of BCR-ABL was determined by RT-PCR. Results: BFA inhibited cell proliferation, induced G2/M cell cycle arrest, and stimulated cell apoptosis in K562 cells.Importantly, for the first time, we revealed that BFA inhibited the activation of BCR-ABL and consequently inhibitedthe activation of its downstream signaling molecules in K562 cells. Moreover, we found BFA degraded BCR-ABLwithout affecting its transcription in K562 cells, and BFA-induced BCR-ABL degradation was related to caspase activation,while not to autophagy or ubiquitinated proteasome degradation pathway. Conclusion: Our present results indicate that BFA acts as a dual functional inhibitor and degrader of BCR-ABL, andBFA is a potential compound for chemotherapeutics to overcome CML.

Natural products derived from marine microorganisms have received great attention as a potential resource of new compound entities for drug discovery. The unique marine environment brings us a large group of sulfur-containing natural products with abundant biological functionality including antitumor, antibiotic, anti-inflammatory and antiviral activities. We reviewed all the 484 sulfur-containing natural products (non-sulfated) isolated from marine microorganisms, of which 59.9% are thioethers, 29.8% are thiazole/thiazoline-containing compounds and 10.3% are sulfoxides, sulfones, thioesters and many others. A selection of 133 compounds was further discussed on their structure–activity relationships, mechanisms of action, biosynthesis, and druggability. This is the first systematic review on sulfur-containing natural products from marine microorganisms conducted from January 1987, when the first one was reported, to December 2020.

Microbial secondary metabolites have long been considered as potential sources of lead compounds for medicinal use due to their rich chemical diversity and extensive biological activities. However, many biosynthetic gene clusters remain silent under traditional laboratory culture conditions, resulting in repeated isolation of a large number of known compounds. The co-culture strategy simulates the complex ecological environment of microbial life by using an ecology-driven method to activate silent gene clusters of microorganisms and tap their metabolic potential to obtain novel bioactive secondary metabolites. In this review, representative studies from 2017 to 2020 on the discovery of novel bioactive natural products from co-cultured microorganisms are summarized. A series of natural products with diverse and novel structures have been discovered successfully by co-culture strategies, including fungus–fungus, fungus–bacterium, and bacterium–bacterium co-culture approaches. These novel compounds exhibited various bioactivities including extensive antimicrobial activities and potential cytotoxic activities, especially when it came to disparate marine-derived species and cross-species of marine strains and terrestrial strains. It could be concluded that co-culture can be an effective strategy to tap the metabolic potential of microorganisms, particularly for marine-derived species, thus providing diverse molecules for the discovery of lead compounds and drug candidates.

In this study, eight natural isocoumarins (1–8) were isolated from a marine-derived Exserohilumsp. fungus. To explore their structure–activity relationship and discover potent antimalarial leads, a small library of 22 new derivatives (1a–1n, 2a, 3a–3c, 4a–4c, and 7a) were semisynthesized by varying the substituents of the aromatic ring and the aliphatic side chains. The natural compound (1) and three semisynthetic derivatives (1d, 1n, and 2a), possessing an all-cisstereochemistry, exhibited strong antiplasmodial activity with IC50values of 1.1, 0.8, 0.4, and 2.6 μM, respectively. Mechanism studies show that 1ninhibits hemozoin polymerization and decreases the mitochondrial membrane potential but also inhibits P. falciparumDNA gyrase. 1nnot only combines different mechanisms of action but also exhibits a high therapeutic index (CC50/IC50= 675), high selectivity, and a notable drug-like profile.

Under the guidance of MS/MS-based molecular networking and HPLC-UV, two new alkaloid racemates, (±)-17-hydroxybrevianamide N (1) and (±)-N1-methyl-17-hydroxybrevianamide N (2), featuring a rare o-hydroxyphenylalanine residue and an imide subunit, were isolated from a soft-coral-derived Aspergillussp. fungus. The true natural products (+)-1and (+)-2were further monitored and obtained from the freshly prepared EtOAc extracts, while (−)-1and (−)-2are artifacts generated during extraction and purification processes. Simultaneously, the structures including absolute configurations of (+)-13S-1, (−)-13R-1, (+)-13S-2, and (−)-13R-2were elucidated on the basis of comprehensive spectroscopic analysis, ECD calculations, and X-ray diffraction data. Interestingly, basic solution promotes the racemization of (+)-1and (−)-1, whereas acidic solution suppresses the transformation. The current research was concerned with the true natural products and their artifacts, providing critical insight into the isolation and identification of natural products.

Two new prenylated indole alkaloids, 17-epi-notoamides Q and M (1and 2), and two new phenyl ether derivatives, cordyols D and E (9and 13), together with 10 known compounds (3–8, 10–12, 14) were isolated from a marine-derived Aspergillussp. fungus. Among them, 1/5and 2/4were pairs of epimers. The planar structures and absolute configurations of the new compounds were determined by extensive NMR spectroscopic data as well as CD spectra. The absolute configuration of 3was confirmed by single-crystal X-ray diffraction analysis for the first time. All isolated metabolites (1–14) and eight synthetic phenyl ether derivatives (12a, 14a–14g) were evaluated for their antibacterial activities in vitro. The polybromide phenyl ether 14gshowed pronounced antibacterial activity against Staphylococcus epidermidiswith an MIC value of 0.556 μM, stronger than that of the positive control ciprofloxacin (MIC = 3.13 μM).

Fumiquinazoline L (1), an alkaloid with a heptacyclic skeleton formed via a bridging hemiaminal linkage, was isolated from a gorgonian-derived Scopulariopsissp. fungus. The structure and absolute configuration of the new compound were identified by comprehensive spectroscopic data and X-ray diffraction analysis. During acid hydrolysis of 1, the isomerization of the valine residue was observed and also studied in different conditions. Fumiquinazoline L (1) showed no cytotoxic or antibacterial activities.

Ten new fungal metabolites, including three hydroisocoumarins, penicimarins A–C (1–3), three isocoumarins, penicimarins D–F (6–8), and four benzofurans, penicifurans A–D (11–14), together with four known isocoumarin derivatives (4, 5, 9, 10), were obtained from the sponge-derived fungus Penicilliumsp. MWZ14-4, collected from the South China Sea. Their planar structures and relative configurations were elucidated by detailed analysis of spectroscopic data and by comparison with related known compounds. The absolute configurations of 1–4were assigned by the modified Mosher’s method and TDDFT ECD calculations together with comparison of their CD spectra. Compound 1represents a rare naturally occurring isocoumarin derivative with 4-substitution, but no substituent at the 3-position. These compounds were evaluated for antibacterial activities and cytotoxic activities in vitro. Among them, penicifuran A (11) exhibited inhibitory activity against Staphylococcus albuswith an MIC value of 3.13 μM.

Under the guidance of MS/MS-based molecular networking, four new cycloheptapeptides, namely, asperheptatides A–D (1–4), were isolated together with three known analogues, asperversiamide A–C (5–7), from the coral-derived fungus Aspergillus versicolor. The planar structures of the two major compounds, asperheptatides A and B (1and 2), were determined by comprehensive spectroscopic data analysis. The absolute configurations of the amino acid residues were determined by advanced Marfey’s method. The two structurally related trace metabolites, asperheptatides C and D (3and 4), were characterized by ESI-MS/MS fragmentation methods. A series of new derivatives (8–26) of asperversiamide A (5) were semisynthesized. The antitubercular activities of 1, 2, and 5–26against Mycobacterium tuberculosisH37Ra were also evaluated. Compounds 9, 13, 23, and 24showed moderate activities with MIC values of 12.5 μM, representing a potential new class of antitubercular agents.

Marine natural products play critical roles in the chemical defense of many marine organisms and are essential, reputable sources of successful drug leads. Sixty-seven 14-membered resorcylic acid lactone derivatives 3–27and 30–71of the natural product zeaenol (1) isolated from the marine-derived fungus Cochliobolus lunatuswere semisynthesized by chlorination, acylation, esterification, and acetalization in one to three steps. The structures of these new derivatives were established by HRESIMS and NMR techniques. All the compounds (1–71) were evaluated for their antialgal and antiplasmodial activities. Among them, 14 compounds displayed antifouling activities against adhesion of the fouling diatoms. In particular, 9and 34exhibited strong and selective inhibitory effects against the diatoms Navicula laevissimaand Navicula exigua(EC50= 6.67 and 8.55 μmol/L), respectively, which were similar in efficacy to those of the positive control SeaNine 211 (EC50= 2.90 and 9.74 μmol/L). More importantly, 38, 39, and 69–71showed potent antiplasmodial activities against Plasmodium falciparumwith IC50values ranging from 3.54 to 9.72 μmol/L. Very interestingly, the five antiplasmodial derivatives displayed non-toxicity in the cytotoxicity assays and the zebrafish embryos model, thus, representing potential promising antiplasmodial drug agents. The preliminary structure–activity relationships indicated that biphenyl substituent at C-2, acetonide at positions C-5′ and C-6′, and tri- or tetra-substituted of acyl groups increased the antiplasmodial activity. Therefore, combining evaluation of chemical ecology with pharmacological models will be implemented as a systematic strategy, not only for environmentally friendly antifoulants but also for structurally novel drugs.

Microketides A and B (1and 2), a pair of new C-11 epimeric polyketides, were obtained from the gorgonian-derived fungus Microsphaeropsissp. RA10-14 collected from the South China Sea. The absolute configurations of 1and 2were assigned by the modified Mosherʼs method, TDDFT-ECD, and NMR calculations. Compounds 1and 2were evaluated for antibacterial, antifungal, and growth inhibition of marine phytoplankton activities. Microketide A (1) exhibited promising inhibitory activity against Pseudomonas aeruginosa, Nocardia brasiliensis, Kocuria rhizophila, and Bacillus anthraciwith the same MIC value as ciprofloxacin (0.19 μg/mL).

An unprecedented cascade β-functionalization/aromatization reaction of N-arylpyrrolidines was established. A series of β-substituted arylpyrroles embedded with trifluoromethyl groups are provided directly from N-arylpyrrolidines. The deuterium-labeling experiments indicate that sequential double hydride transfer processes serve as the key steps in this transformation.

A novel perylenequinone-related compound, alternatone A (1), with an unprecedented tricyclo[6.3.1.02,7] dodecane skeleton, together with three known perylenequinones, altertoxin I (2), stemphyperylenol (3), and alterperylenol (4), was isolated from the soft-coral-derived fungus Alternaria alternataL3111′. Their structures including absolute configurations were elucidated on the basis of comprehensive spectroscopic analysis, electronic circular dichroism calculations, and X-ray diffraction data. Compound 4showed cytotoxicity against A-549, HCT-116, and HeLa cell lines with IC50values of 2.6, 2.4, and 3.1 μM, respectively. A possible biosynthetic pathway of 1was proposed.

Metabolites from marine organisms have proven to be a rich source for the discovery of multiple potent bioactive molecules with diverse structures. In recent years, we initiated a program to investigate the diversity of the secondary metabolites from marine invertebrates and their symbiotic microorganisms collected from the South China Sea. In this review, representative cases are summarized focusing on molecular diversity, mining, and application of natural products from these marine organisms. To provide a comprehensive introduction to the field of marine natural products, we highlight typical molecules including their structures, chemical synthesis, bioactivities and mechanisms, structure–activity relationships as well as biogenesis. The mining of marine-derived microorganisms to produce novel secondary metabolites is also discussed through the OSMAC strategy and via partial chemical epigenetic modification. A broad prospectus has revealed a plethora of bioactive natural products with novel structures from marine organisms, especially from soft corals, gorgonians, sponges, and their symbiotic fungi and bacteria.

Coral-derived microorganisms are known for their inherent ability to produce novel products of pharmaceutical importance. Nearly 260 marine natural products (MNPs) have been isolated from coral-derived microorganisms till 2014. In the last three years, 118 MNPs have been isolated from coral-associated microorganisms including 46 new compounds, two with a novel skeleton, and four new natural products. Most of them exhibited in vitro or in vivo activities against tumor cell lines, parasites, pathogenic bacteria, fungi and virus. We reviewed the natural products reported from 2015 to 2017 that have a wide range of bioactivities against different biological targets.

Six new sordarin tetracyclic diterpene glycosides, moriniafungins B–G (1–6), and a new sordaricin tetracyclic diterpene, sordaricin B (8), together with two known analogues, moriniafungin (7) and sordaricin (9), were isolated from the zoanthid-derived fungus Curvularia hawaiiensisTA26-15. The structures of the new compounds were elucidated by comprehensive analyses of spectroscopic data, including 1D and 2D NMR and MS data. Compounds 1–6represent the first case of sordarins from marine-derived fungi possessing a sordarose with a spiro 1,3-dioxolan-4-one ring, which is rare in the nature. Compound 4showed antifungal activity against Candida albicansATCC10231 with an MIC value of 2.9 μM.

A challenging problem in natural product discovery is to rapidly dereplicate known compounds and expose novel ones from complicated components. Herein, integrating the LC-MS/MS-dependent molecular networking and 1H NMR techniques efficiently and successfully enabled the targeted identification of seven new cyclohexadepsipeptides, chrysogeamides A–G (1–7), from the coral-derived fungus Penicillium chrysogenum(CHNSCLM-0003) which was targeted from a library of marine-derived Penicilliumfungi. Compound 4features a rare 3-hydroxy-4-methylhexanoic acid (HMHA) moiety which was first discovered from marine-derived organisms. Interestingly, isotope-labeling feeding experiments confirmed that 13C1-l-Leu was transformed into 13C1-d-Leu moiety, indicating that d-Leu could be isomerized from l-Leu. Compounds 1and 2obviously promoted angiogenesis in zebrafish at 1.0 μg/mL with nontoxic to embryonic zebrafish at 100 μg/mL. Combining molecular networking with 1H NMR as a discovery tool will be implemented as a systematic strategy, not only for known compounds dereplication but also for untapped reservoir discovery.

We reported previously the discovery of the potent antimalarial 40-membered macrolide bastimolide A (1) from the tropical marine cyanobacterium Okeania hirsute. Continued investigation has led to the discovery of a new analogue, bastimolide B (2), a 24-membered polyhydroxy macrolide with a long aliphatic chain and unique terminal tert-butyl group. Its complete structure was determined by a combination of extensive spectroscopic methods and comparative analysis of its methanolysis products with those of bastimolide A. A methanolysis mechanism for bastimolide A is proposed, and one unexpected isomerization product of the C2–C3 double bond, 2-(E)-bastimolide A (3), was obtained. Bastimolide B (2) showed strong antimalarial activity against chloroquine-sensitive Plasmodium falciparumstrain HB3. A preliminary investigation of the structure–activity relationship based on six analogues revealed the importance of the double bond as well as the 1,3-diol and 1,3,5-triol functionalities.

Coral-derived microorganisms have been a major focus of many research efforts on marine ecology in recent decades. Importantly, research on bioactive compounds from these diverse microorganisms, which include fungi and bacteria, has experienced an explosive growth during the past five years. This has unveiled the ecological roles of these microorganisms, which prevent antifouling, inhibit pathogenic bacteria, and deter predators in ocean ecosystems. Moreover, the structural diversity and pharmacological activity of the compounds produced by these microorganisms have also been studied extensively, leading not only to an understanding their roles within ecosystems, but also the potential value of their use in human health. In this review, 258 marine natural products, including polyketides, terpenoids, meroterpenoids, alkaloids, peptides, shikimates and lipids, all discovered in the past 24 years, are presented. 146 references are cited.

Three new azaphilone derivatives, pinophilins D–F (1–3), and one new diphenyl ether derivative, hydroxypenicillide (10), together with nine known compounds (4–9, 11–13), were isolated from the gorgonian-derived fungus Penicillium pinophilumXS-20090E18. Their structures including absolute configurations were determined by spectroscopic data, chemical conversions, the ECD exciton chirality method, and ECD calculations. Compounds 10–13exhibited inhibitory activity against the larval settlement of the barnacle Balanus amphitriteat nontoxic concentrations. Compounds 10and 11showed cytotoxicity against Hep-2, RD, and HeLa cell lines.

Twelve new chromone derivatives, corynechromones A–L (1–12), were isolated from the sponge-derived fungus Corynespora cassiicolaXS-200900I7. Among them, 1/2, 3/4, 5/6, and 7/8were pairs of epimers. The planar structures were determined by extensive NMR spectroscopic data. The absolute configurations of 1–10were assigned by the modified Mosher’s method and TDDFT ECD calculations together with comparison of their CD spectra. These are the first chromone derivatives reported from the genus Corynespora. A possible rule to determine the absolute configurations at C-2 in chromone derivatives by CD was proposed.

Two new prenylated dihydroquinolone derivatives, 22-O-(N-Me-l-valyl)aflaquinolone B (1) and 22-O-(N-Me-l-valyl)-21-epi-aflaquinolone B (2), and two known analogues, aflaquinolones A (3) and D (or a diastereomer of D, 4), were isolated from the mycelia of a gorgonian-derived Aspergillussp. fungus. The structures of the new compounds were elucidated by spectroscopic methods, ECD spectra, Marfey’s method, and chemical conversion. Compounds 1and 2display an unusual esterification of N-Me-l-Val to the side-chain prenyl group. Compound 2exhibited outstanding anti-RSV activity with an IC50value of 42 nM, approximately 500-fold stronger than that of the positive control ribavirin (IC50= 20 μM), and showed a comparatively higher therapeutic ratio (TC50/IC50= 520).

Three new lumazine peptides, penilumamides B–D (2–4), and one known analogue, penilumamide (1), together with a new cyclic pentapeptide, asperpeptide A (5), were isolated from the gorgonian-derived fungus Aspergillussp. XS-20090B15. Among them, 2was obtained from the feeding culture with l-methionine of this strain. All structures were elucidated by spectroscopic methods and chemical derivatization. Compounds 1–4are rare lumazine peptides, of which 1and 3are formed from 2by oxidation of the l-methionine residue.

Four new steroids with an acetoxy linked at the end of the side chain, echrebsteroids A–D (1–4) were obtained from the South China Sea gorgonian Echinogorgia rebekka. The absolute configurations of 1–3were determined using the modified Mosher’s method on the hydrolysis products. The isolation of the pair of epimers (2and 3) represents the first reported separation of C-25 epimers of 26-acetoxy steroids. The (25R)-epimer (3) exhibited promising antiviral activity against respiratory syncytial virus with an IC50value of 0.19 μM and a comparatively higher therapeutic ratio (TC50/IC50= 128).

Brefeldin A (BFA), a well-known natural Arf-GEFs inhibitor, is effective against hepatocellular carcinoma (HCC), while the poor solubility, serious toxicity, and short half-life limit its potential. Herein, distinct corresponding prodrugs of BFA, including esters 1–15, carbonates 16–24and 30–32, and carbamates 25–29, were synthesized and evaluated. CHNQD-01255(16) with improved aqueous solubility (15–20 mg/mL) demonstrated favorable pharmacokinetic profiles. It behaved as expected by undergoing rapid conversion to BFA in vivo, and achieved sufficient high plasma exposure, prolonged half-life, as well as the improved bioavailability of BFA (F= 18.96%). Meanwhile, CHNQD-01255significantly suppressed tumor growth (TGI = 61.0%) at a dose of 45 mg/kg (p.o.) in the xenograft model. Notably, the improved safety profile of CHNQD-01255(MTD > 750 mg/kg, p.o.) was confirmed to be superior to that of BFA (MTD < 506 mg/kg). Overall, CHNQD-01255may serve as a safe and effective new anti-HCC prodrug.

Chemical investigation of a marine-derived fungus Nigrosporasp., isolated from an unidentified sea anemone, yielded two new hydroanthraquinone analogues, 4a-epi-9α-methoxydihydrodeoxybostrycin (1) and 10-deoxybostrycin (2), together with seven known anthraquinone derivatives (3–9). The structures of the two new compounds were established through extensive NMR spectroscopy as well as a single-crystal X-ray diffraction analysis using Cu Kα radiation. The antibacterial activities of compounds 1–9and 10 acetyl derivatives (6a, 7a, 8a–8g, 9a) were evaluated in vitro. Compound 6a, the acetylated derivative of 6, exhibited promising activity against Bacillus cereuswith an MIC value of 48.8 nM, which was stronger than that of the positive control ciprofloxacin (MIC = 1250 nM). Analysis of the antibacterial screening data for the metabolites and their acetyl derivatives revealed the key structural features required for this activity.

Five new hydroanthraquinone derivatives, tetrahydroaltersolanols C–F (1–4) and dihydroaltersolanol A (5), and five new alterporriol-type anthranoid dimers, alterporriols N–R (12–16), along with seven known analogues (6–11and 17), were isolated from the culture broth and the mycelia of Alternariasp. ZJ-2008003, a fungus obtained from a Sarcophytonsp. soft coral collected from the South China Sea. Their structures and the relative configurations were elucidated using comprehensive spectroscopic methods including 1D and 2D NOE spectra as well as single-crystal X-ray crystallography. Compound 13represents the first isolated alterporriol dimer with a C-4–C-4′ linkage, and the absolute configuration of 4was determined using the modified Mosher’s method. Compounds 1and 15exhibited antiviral activity against the porcine reproductive and respiratory syndrome virus (PRRSV), with IC50values of 65 and 39 μM, respectively. Compound 14showed cytotoxic activity against PC-3 and HCT-116 cell lines, with IC50values of 6.4 and 8.6 μM, respectively.

Three new 14-membered resorcylic acid lactones, two with a rare natural acetonide group and one with a 5-chloro-substituted lactone, named cochliomycins A−C (1−3), together with four known analogues, zeaenol (4), LL-Z1640-1 (5), LL-Z1640-2 (6), and paecilomycin F (7), were isolated from the culture broth of Cochliobolus lunatus, a fungus obtained from the gorgonian Dichotella gemmaceacollected in the South China Sea. Their structures and the relative configurations of 1−3were elucidated using comprehensive spectroscopic methods including NOESY spectra and chemical conversions. A transetherification reaction was also observed in which cochliomycin B (2) in a solution of CDCl3slowly rearranged to give cochliomycin A (1) at room temperature. These resorcylic acid lactones were evaluated against the larval settlement of barnacle Balanus amphitrite, and antifouling activity was detected for the first time for this class of metabolites. The antibacterial and cytotoxic activities of these compounds were also examined.

The structure of penicillazine has been revised on the basis of hydrolysis reaction. Its absolute stereochemistry has been confirmed by X-ray diffraction using copper radiation. Eight new penicillazine derivatives (1-8) were prepared and some of them showed higher levels of activity than penicillazine against α-glucosidase and Human DNA topoisomerase I.

One new terphenyl glycoside (1), gliocladinin D, together with 4 known compounds (2-5) were isolated from the sponge-derived fungus Trichoderma reesei(HN-2016-018). The structure of the new compound was elucidated by the comprehensive spectroscopic analysis, including 1-dimensional and 2-dimensional nuclear magnetic resonance, and high-resolution electrospray ionization mass spectrometry. Compound 3exhibited moderate Topo I inhibitory activity.

Two new steroidal glycosides, fragilioside A (1) and fragilioside B (2), along with five known compounds (3–7) were isolated from the gorgonian Dichotella fragilis(Ridleg) collected from the South China Sea. The structures of the new compounds (1and 2) were elucidated by comprehensive analysis of spectral data, especially 2D NMR. The brine shrimp lethality and antifouling activity of the isolated compounds were also evaluated.

Aspergilone A(I) possessing an azaphilone structure, and its symmetrical dimer with a unique methylene bridge, aspergilone B(II), are isolated from the culture broth of the marine derived title plant.

The new alkaloid penicinoline (I) is isolated from a mangrove endophytic fungus.

One new cembrane diterpenoid, named sarcolactone A (1), along with five known compounds (2–6) were isolated from the soft coral Sarcophyton infundibuliformecollected from the South China Sea. The structure of sarcolactone A (1) was elucidated by comprehensive analysis of spectral data, especially 2D-NMR spectra (1H-1H COSY, HMBC and NOESY). All the compounds were evaluated for their brine shrimp lethality and antifouling activities.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.