Lichens are symbiotic organisms comprised of mycobionts and photobiont partners. They are known to produce bioactive secondary metabolites and most of these are biosynthesized by mycobionts. Investigations of cultures of isolated lichen-associated fungi have shown promise for the discovery of cytotoxic compounds. Thus, the lichen-associated fungus was studied for its potential to produce novel compounds and the new sterols (20*)-hydroxy-24(28)-dehydrocampesterol (), 7α-methoxy-8β-hydroxypaxisterol (), 14--epicoccarine A () and 14--epicoccarine B (), as well as the known compound PF1140 (), were isolated. The structures of these compounds were elucidated using methods including nuclear magnetic resonance (NMR) spectroscopy and high-resolution electrospray ionization mass spectrometry (HRESIMS). Following cytotoxicity assays, compound demonstrated activity against the pancreatic adenocarcinoma epithelial HPAC cell line at 17.76 ± 5.35 μM. Since the structures of compounds and were very similar to tetramic acid derivatives that were reported to be biosynthesized from a polyketide synthase- non-ribosomal peptide synthetase (PKS-NRPS) hybrid pathway, a plausible biosynthetic route for production in is proposed herein.

The genus has several species, most notably , with reported cytotoxic and venotonic effects. The angiogenic effect from is of interest given the current limitations of anti-angiogenic therapeutics. (Willdenow), known as the Ohio Buckeye Tree is a species native to North America with reported medicinal use by the Native Americans. Previous phytochemical studies have focused on the seed and leaf contents of the species, with most of them reporting cytotoxic activity. In this study, we assessed preliminary anti-angiogenic activity and toxicity of isolated compounds from the bark of utilizing a zebrafish () model. Procyanidin A2 and epicatechin, two pure isolates, were tested using zebrafish and gave an anti-angiogenic response, suggesting an underlying mechanism involved in vascular development.

Due to the emergence of resistance, the World Health Organization considers Gram-negative pathogen a top priority for therapeutic development. Using this priority pathogen and a phenotypic, agar plate-based assay, a unique library of extracts from 2,500 diverse fungi was screened for antimicrobial activity against a highly virulent, drug-resistant strain of (AB5075). The most potent hit from this screen was an extract from the fungus sp., which was found to produce pyridoxatin. Another active extract from the fungi was characterized and yielded trichokonin VII and trichokonin VIII. Evaluation of pyridoxatin against (AB5075) in a broth microdilution assay revealed a minimum inhibitory concentration (MIC) of 38 μM, compared to the known antibiotic levofloxacin with MIC of 28 μM. Mass spectrometry, Marfey's analysis and nuclear magnetic resonance spectroscopy analyses confirmed the structures of trichokonins VII and VIII to be consistent with previous reports. In an model, pyridoxatin tested at 150 mg/kg exhibited minimal toxicity (90% survival) and promising antimicrobial efficacy (50% survival) after 5 days. Trichokonins VII and VIII tested at 150 mg/kg were toxic to , with 20% survival and 40% survival after 5 days, respectively. The findings of this project suggest that pyridoxatin may serve as a lead compound for the development of antimicrobials against . They also demonstrate the value of the phenotypic screening approach employed herein.

A chemical library was constructed based on the resin acids (abietic, dehydroabietic, and 12-formylabietic) and its diene adducts (maleopimaric and quinopimaric acid derivatives). The one-pot three-component CuCl-catalyzed aminomethylation of the abietane diterpenoid propargyl derivatives was carried out by formaldehyde and secondary amines (diethylamine, pyrrolidine, morpholine, and homopiperazine). All compounds were tested for cytotoxicity and antiviral activity against influenza virus A/Puerto Rico/8/34 (H1N1) in MDCK cells and SARS-CoV-2 pseudovirus in BHK-21-hACE2 cells. Among 21 tested compounds, six derivatives demonstrated a selectivity index (SI) higher than 10, and their IC values ranged from 0.19 to 5.0 μM. Moreover, two derivatives exhibited potent anti-SARS-CoV-2 infection activity. The antiviral activity and toxicity strongly depended on the nature of the diterpene core and heterocyclic substituent. Compounds and bearing pyrrolidine moieties demonstrated the highest virus-inhibiting activity with SIs of 128.6 and 146.8, respectively, and appeared to be most effective when added at the time points 0-10 and 1-10 h of the viral life cycle. Molecular docking and dynamics modeling were adopted to investigate the binding mode of compound into the binding pocket of influenza A virus M2 protein. Compound with a pyrrolidine group at C20 of 17-formylabietic acid was a promising anti-SARS-CoV-2 agent with an EC of 10.97 µM and a good SI value > 18.2. Collectively, our data suggested the potency of diterpenic Mannich bases as effective anti-influenza and anti-COVID-19 compounds.

A new isoflavonoid, xanthocerin J, along with previously described xanthocerin A, were isolated from a methanol extract of aerial parts of a traditional American Indian herb, Pursh (Asteraceae). The structures of these compounds were characterized using mass spectrometry and NMR based on an isolation protocol using magnetic microbead affinity selection screening (MagMASS) for ligands to the estrogen receptor alpha (ERα). These compounds bound to ERα from an active fraction that exhibited dose-dependent antiestrogenic activity in the Ishikawa assay. However, these compounds did not exhibit antiestrogenic activity in the cell-based Ishikawa assay. Xanthocerin A and J may exhibit synergistic or additive activity with other compounds found in which needs further exploration. This work highlights the potential of as a prospect for the future discovery of compounds for women's health related to estrogen pathways.

Phytochemical investigation of the aerial parts of led to the isolation of secondary metabolites belonging to the spermidine alkaloid, glycoside, depsidone and phenol classes. Of the eleven secondary metabolites isolated in this study, two spermidine alkaloids, dovyalicins H () and I (), which belong to a rare group among this class, and six glycosides () are previously undescribed. The structures of all new isolates were determined by interpretation of spectroscopic and spectrometric data. In this report, the structural elucidation of these unprecedented secondary metabolites () is described.

Phytochemical profiling of a hybrid species of willow, × L. ( Thunb. × W.C. Cheng ex G.Zhu) revealed four sulfated flavonoids, which were then isolated from young stem tissue. The structures of dihydroflavonols (flavanonols) taxifolin-7-sulfate and dihydrokaempferol-7-sulfate and flavanones, eridictyol-7-sulfate and naringenin-7-sulfate were elucidated through NMR spectroscopy and high-resolution mass spectrometry. The identified sulfated flavanones and dihydroflavonols have not been previously seen in plants, but the former have been partially characterised as metabolites in mammalian metabolism of dietary flavonoids. In addition to providing full spectroscopic characterisation of these metabolites for the first time, we also compared the antioxidant properties, the DPPH radical scavenging assay, of the parent and sulfated flavanones, which showed that 7-sulfation of taxifolin and eriodictyol attenuates but does not remove anti-oxidant activity.

A new 2-arylbenzofuran, sesbagrandiflorain C (), together with four known compounds, 2-(3,4-dihydroxy-2-methoxyphenyl)-4-hydroxy-6-methoxybenzofuran-3-carbaldehyde (, 2-(4-hydroxy-2-methoxyphenyl)-5,6-dimethoxybenzofuran-3-carboxaldehyde (), sesbagrandiflorain A () and sesbagrandiflorain B (), have been isolated from the stem bark of an Indonesian plant, (L.) Pers. The chemical structure of compound was elucidated by UV, IR, MS, and NMR spectroscopic techniques. The proton and carbon NMR resonances of were also compared with the predicted chemical shifts obtained from DFT quantum mechanical calculations with Gaussian. None of the compounds showed antibacterial activity against , , , and in an agar diffusion assay. However, sesbagrandiflorains A () and B () exhibited moderate activity against H37Rv. In addition, compounds - have moderate cytotoxicity against HeLa, HepG2, and MCF-7 cancer cell lines.

Four novel lupane-type lupane-type triterpenoids (including three norlupane-type triterpenoids), 17β-hydroxy-28-norlup-20(29)-en-3-one (), 3β,17β-dihydroxy-28,30-bisnorlupan-20-one (), 3β-hydroxy-20-oxo-30-norlupan-28-al () and lup-20(29)-ene-3,23,30-triol (), were isolated together with ten known lupane triterpenoids (~) from the bark of forma . Their structures were determined from 1D- and 2D-NMR analysis and comparison of their spectroscopic data with literature values. The known compounds (~) were reported for the first time from this plant.

Herbarium voucher specimens are used primarily for taxonomic confirmation. However, they also afford a record of the metabolic profile of a plant, potentially at the time it was collected, or at the very least, at the time of analysis. Even with the enhanced sensitivity of modern analytical techniques, analysis of the metabolites of a herbarium voucher requires removal and consumption of at least part of an entire specimen. We present herein a non-destructive method to analyze the metabolites of herbarium voucher specimens with the droplet-liquid microjunction-surface sampling probe (droplet probe) coupled to ultra-performance liquid chromatography and highresolution mass spectrometry. As proof of concept, a herbarium voucher specimen of (mangosteen) was utilized due to the well-characterized xanthones biosynthesized by this plant, which are of interest as potential anticancer agents. Also, the juice of the fruits of this plant is used widely in the United States and in other countries as a botanical dietary supplement. Metabolite profiles of the sampled surfaces were compared to a subset of xanthone standards. Using this innovative method on the herbarium voucher specimen, we were able to readily identify cytotoxic prenylated xanthones while maintaining the integrity of the entire specimen.

In an attempt to explore the biosynthetic potential of endosymbiotic fungi, the secondary metabolite profiles of the endophytic fungus, sp. FL0768, cultured under a variety of conditions were investigated. In potato dextrose broth (PDB) medium, sp. FL0768 produced the heptaketides, herbaridine A (), herbarin (), 1-hydroxydehydroherbarin (), scorpinone (), and the methylated hexaketide 9,11-(+)-ascosalitoxin (). Incorporation of commonly used epigenetic modifiers, 5-azacytidine and suberoylanilide hydroxamic acid, into the PDB culture medium of this fungus had no effect on its secondary metabolite profile. However, the histone acetyl transferase inhibitor, anacardic acid, slightly affected the metabolite profile affording scorpinone () as the major metabolite together with 1-hydroxydehydroherbarin () and a different methylated hexaketide, ascochitine (). Intriguingly, incorporaion of Cu into the PDB medium enhanced production of metabolites and drastically affected the biosynthetic pathway resulting in the production of pentaketide dimers, palmarumycin CE (), palmarumycin CP (), and palmarumycin CP (), in addition to ascochitine (). The structure of the new metabolite was established with the help of spectroscopic data and by MnO oxidation to the known pentaketide dimer, palmarumycin CP (). Biosynthetic pathways to some metabolites in sp. FL0768 are presented and possible effects of AA and Cu on these pathways are discussed.

Diterpenoid alkaloids with remarkable chemical properties and biological activities are frequently found in plants of the genera , , and . Accordingly, several C-diterpenoid alkaloid components from cv. Pacific Giant, as well as their derivatives, exhibited cytotoxic activity against lung, prostate, nasopharyngeal, and vincristine-resistant nasopharyngeal cancer cell lines. Four new C-diterpenoid alkaloids, elapacigine (), -deethyl--formylpaciline (), -deethyl--formylpacinine (), and -formyl-4,19-secoyunnadelphinine (), together with 11 known C-diterpenoid alkaloids were isolated in a phytochemical investigation on the seeds of cv. Pacific Giant. Their structures were elucidated by extensive spectroscopic methods including NMR (1D and 2D), IR, and MS (HRMS). Three of the new C-diterpenoid alkaloids (-) and five of the known diterpenoid alkaloids were evaluated for cytotoxic activity against five human tumor cell lines.

Phytochemical investigation of the aerial parts of Pourr. resulted in the isolation and characterization of a new isoflavan, ()-2',4'-dihydroxy-3'-methoxy-6,7-methylenedioxyisoflavan- 4-ol (), and a new monoterpene, ()-4-hydroxy-2,2,6-trimethyl-9-oxabicyclo [4.2.1] non-1(8)-en-7-one (), together with four known flavonoids: geinstein , chrysin , chrysin -7--β-D-glucopyranoside and 2″--α-L-rhamnosylorientin . The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis, including 1D, 2D NMR (H, C, COSY, TOCSY, HMBC and HSQC) and HRESIMS. The absolute configurations of and were established by the comparison of experimental and calculated electronic circular dichroism (ECD) spectra.

In its fourth year, the CASMI 2016 contest was organized to evaluate current chemical structure identification strategies for 19 natural products using high-resolution LC-MS and LC-MS/MS challenge datasets using automated methods with or without the combination of other tools. These natural products originate from plants, fungi, marine sponges, algae, or micro-algae. Every compound annotation workflow must start with determination of elemental compositions. Of these 19 challenges, one was excluded by the organizers after submission. For the remaining 18 challenges, three software programs were used. MS-FINDER version 1.62 was able to correctly identify 89% of the molecular formulas using an internal database that comprised of 13 metabolomics repositories with 45,181 formulas. SIRIUS correctly identified 61% compositions using PubChem formulas and Seven Golden Rules correctly identified 83% by using the Dictionary of Natural Products as a targeted database. Next, we performed structural dereplication for which we used the consensus formula from the three software programs. We submitted two solution sets for these challenges. In the first solution set, , we only used the internal MS-FINDER functions for predicting and ranking structures, correctly identifying 53% of the structures as top-hit, 72% within the top-3 structures, and 78% within the top-10 hits. For our second set, , we used both MS-FINDER predictions as well as MS/MS queries against the commercial NIST 14, METLIN, and the public MassBank of North America libraries. Here we correctly identified 78% of the structures as top-hit and 83% within the top-3 hits. Three challenge spectra remained unidentified in either of our submissions within the top-10 hits.

The Critical Assessment of Small Molecule Identification (CASMI) contest is an initiative designed as an unbiased test of manual and automated strategies for the identification of small molecules from raw mass spectrometric data. In this contest, the participants are provided a set of high resolution MS and MS/MS data and asked to identify the unknown structure. CASMI 2016 is the fourth round of this contest in which the author participated in Category 1: Best Identification of Natural Products using a manual approach. The provided high resolution mass spectrometric data were interpreted manually using a combination of fragment and neutral loss analysis, literature consultation, manual database searches, deductive logic and experience. Out of 18 challenges, the author submitted correct structures as lead candidates for 14 challenges and 2 ranked candidate for four challenges and was declared the winner of this category Pitfalls and challenges encountered during data interpretation are discussed.

Complete structural elucidation of natural products is commonly performed by nuclear magnetic resonance spectroscopy (NMR), but annotating compounds to most likely structures using high-resolution tandem mass spectrometry is a faster and feasible first step. The CASMI contest 2016 (Critical Assessment of Small Molecule Identification) provided spectra of eighteen compounds for the best manual structure identification in the natural products category. High resolution precursor and tandem mass spectra (MS/MS) were available to characterize the compounds. We used the Seven Golden Rules, Sirius2 and MS-FINDER software for determination of molecular formulas, and then we queried the formulas in different natural product databases including DNP, UNPD, ChemSpider and REAXYS to obtain molecular structures. We used different in-silico fragmentation tools including CFM-ID, CSI:FingerID and MS-FINDER to rank these compounds. Additional neutral losses and product ion peaks were manually investigated. This manual and time consuming approach allowed for the correct dereplication of thirteen of the eighteen natural products.

The study presented herein constitutes an extensive investigation of constituents in L. (Ranunculaceae) leaves. It describes the isolation and identification of two previously unknown compounds, 3,4-dimethoxy-2-(methoxycarbonyl)benzoic acid () and 3,5,3'-trihydroxy-7,4'-dimethoxy-6,8--dimethyl-flavone (), along with the known compounds (±)-chilenine (), (2)-5,4'-dihydroxy-6--methyl-7-methoxy-flavanone (), 5,4'-dihydroxy-6,8-di--methyl-7-methoxy-flavanone (), noroxyhydrastinine (), oxyhydrastinine () and 4',5'-dimethoxy-4-methyl-3'-oxo-(1,2,5,6-tetrahydro-4-1,3-dioxolo-[4',5':4,5]-benzo[1,2-]-1,2-oxazocin)-2-spiro-1'-phtalan (). Compounds have been reported from other sources, but this is the first report of their presence in extracts. A mass spectrometry based assay was employed to demonstrate bacterial efflux pump inhibitory activity against for , with an IC value of 180 ± 6 μM. This activity in addition to that of other bioactive compounds such as flavonoids and alkaloids, may explain the purported efficacy of for treatment of bacterial infections. Finally, this report includes high mass accuracy fragmentation spectra for all compounds investigated herein which were uploaded into the Global Natural Products Social molecular networking library and can be used to facilitate their future identification in or other botanicals.

Bioassay guided fractionation and chemical investigation of the ethanolic extract of the aerial parts of Laxm. (Sapindaceae), resulted in the isolation and identification of three new triterpenoid saponins named Paniculatosoid A-C, along with eleven known compounds. The structures of the isolated compounds were elucidated using 1D and 2D NMR experiments, HRESIMS, and comparison with literature data. The occurrence of tridesmosidic saponin is reported for the first time from family Sapindaceae, as well as it is rarely found in natural saponins. Compounds were evaluated for their antibacterial, antifungal, antimalarial and antileishmanial activities. Compound 12 showed weak antibacterial activity against with an IC value of 101 μM. Compounds and showed antimalarial activity against chloroquine-sensitive (D6) protozoan with IC values of 6.46 and 6.95 μM, and against chloroquine-resistant (W2) protozoan with IC values of 9.34 and 4.18 μM.

The potential of fungal endophytes to alter or contribute to plant chemistry and biology has been the topic of a great deal of recent interest. For plants that are used medicinally, it has been proposed that endophytes might play an important role in biological activity. With this study, we sought to identify antimicrobial fungal endophytes from the medicinal plant goldenseal ( L., Ranunculaceae), a plant used in traditional medicine to treat infection. A total of 23 fungal cultures were obtained from surface-sterilized samples of roots, leaves and seeds. Eleven secondary metabolites were isolated from these fungal endophytes, five of which had reported antimicrobial activity. plant material was then analyzed for the presence of fungal metabolites using liquid chromatography coupled to high resolving power mass spectrometry. The antimicrobial compound alternariol monomethyl ether was detected both as a metabolite of the fungal endophyte spp. isolated from seeds, and as a component of an extract from the seed material. Notably, fungi of the genus were isolated from three separate accessions of plant material collected in a time period spanning 5 years. The concentration of alternariol monomethyl ether (991 mg/kg in dry seed material) was in a similar range to that previously reported for metabolites of ecologically important fungal endophytes. The seed extracts themselves, however, did not possess antimicrobial activity.

Microseiramide (1), a cyclic heptapeptide, was isolated from a sample of the freshwater cyanobacterium Microseira sp. UIC 10445 collected in a shallow lake in Northern Indiana. Taxonomic identification of UIC 10445 was performed by a combination of morphological and phylogenetic characterization. Phylogenetic analysis revealed that UIC 10445 was a member of the recently described genus Microseira, which is phylogenetically distinct from the morphologically similar genera. Moorea and Lyngbya. The planar structure of microseiramide (1) was determined by extensive 1D and 2D NMR experiments as well as HRESIMS analysis. The absolute configurations of amino acid residues were determined using acid hydrolysis followed by the advanced Marfey's analysis. microseiramide (1) is the first cyclic peptide reported from a Microseira sp., and the structure of microseiramide (1) is distinct from the previously known metabolites from cyanobacteria of the genera Moorea and Lyngbya.