Journal of Natural Products

cis -12-oxo-Phytodieneoic acid-α-monoglyceride ( 1 ) was isolated from Arabidopsis thaliana . The chemical structure of 1 was elucidated based on exhaustive 1D and 2D NMR spectroscopic measurements and supported by FDMS and HRFDMS data. The absolute configuration of the cis -OPDA moiety in 1 was determined by comparison of 1 H NMR spectra and ECD measurements. With respect to the absolute configuration of the β-position of the glycerol backbone, the 2:3 ratio of ( S ) to ( R ) was determined by making ester-bonded derivatives with ( R )-(+)-α-methoxy-α-trifluoromethylphenylacetyl chloride and comparing 1 H NMR spectra...

Actinomycetes are prolific producers of natural products, particularly antibiotics. However, a significant proportion of its biosynthetic gene clusters (BGCs) remain silent under typical laboratory conditions. This limits the effectiveness of conventional isolation methods for the discovery of novel natural products. Genetic interventions targeting the activation of silent gene clusters are necessary to address this challenge. Streptomyces antibiotic regulatory proteins (SARPs) act as cluster-specific activators and can be used to target silent BGCs for the discovery of new antibiotics...

Ansamycins, represented by the antituberculosis drug rifamycin, are an important family of natural products. To obtain new ansamycins, Streptomyces rapamycinicus IMET 43975 harboring an ansamycin biosynthetic gene cluster was fermented in a 50 L scale, and subsequent purification work led to the isolation of five known and four new analogues, where hygrocin W ( 2 ) belongs to benzoquinonoid ansamycins, and the other three hygrocins, hygrocins X-Z ( 6 - 8 ), are new seco-hygrocins. The structures of ansamycins ( 1 - 8 ) were determined by the analysis of spectroscopic (1D/2D NMR and ECD) and MS spectrometric data...

An unprecedented di- seco -indole diterpenoid, peniditerpenoid A ( 1 ), and a rare N -oxide-containing indole diterpenoid derivative, peniditerpenoid B ( 2 ), together with three known ones ( 3 - 5 ), were obtained from the mangrove-sediment-derived fungus Penicillium sp. SCSIO 41411. Their structures were determined by the analysis of spectroscopic data, quantum chemical calculations, and X-ray diffraction analyses. Peniditerpenoid A ( 1 ) inhibited lipopolysaccharide-induced NF-κB with an IC50 value of 11 μM and further effectively prevented RANKL-induced osteoclast differentiation in bone marrow macrophages...

Psammaplins are sulfur containing bromotyrosine alkaloids that have shown antitumor activity through the inhibition of class I histone deacetylases (HDACs). The cytotoxic properties of psammaplin A ( 1 ), the parent compound, are related to peroxisome proliferator-activated receptor γ (PPARγ) activation, but the mechanism of action of its analogs psammaplin K ( 2 ) and bisaprasin ( 3 ) has not been elucidated. In this study, the protective effects against oxidative stress of compounds 1 - 3 , isolated from the sponge Aplysinella rhax , were evaluated in SH-SY5Y cells...

A search for anti-trypanosomal natural compounds from plants collected in El Salvador, a country particularly endemic for Chagas disease, resulted in the isolation of five lignan-type compounds ( 1 - 5 ) from Peperomia pseudopereskiifolia . The lignan derivatives 1 , 2 , and 4 are new. Their absolute configuration was determined by chemical derivatization. Compounds 1 , 5 , 6 , and 8 exhibited anti-trypanosomal activity against the amastigote form of T. cruzi comparable to that of the existing drug benznidazole...

Two unusual naphthoquinones, named here as pleonotoquinones A ( 1 ) and B ( 2 ), were isolated along with two known anthraquinones ( 3 and 4 ) via chromatographic separations of an ethyl acetate extract of the roots of Pleonotoma jasminifolia . Compounds 1 and 2 are the first examples of quinones bearing a 2-methyloxepine moiety. The compounds were isolated with the aid of mass spectrometry and molecular networking, and their structures were resolved using 1D and 2D NMR and HRESIMS data. The isolated compounds were evaluated for their antiproliferative activity against human cancer cell lines, and compounds 1 and 2 displayed cytotoxicity against human colon cancer HCT116 cells (IC50 = 2...

Three new cyclic heptapeptides, talaromides A-C ( 1 - 3 ), were isolated from cultures produced by the fungus Talaromyces siglerae (Ascomycota), isolated from an unidentified sponge. The structures, featuring an unusual proline-anthranilic moiety, were elucidated by analysis of spectroscopic data and chemical transformations, including the advanced Marfey's method and GITC derivatization. Talaromides A and B inhibited migration activity against PANC-1 human pancreatic cancer cells without significant cytotoxicity...

Epithelial ovarian cancer is among the deadliest gynecological tumors worldwide. Clinical treatment usually consists of surgery and adjuvant chemo- and radiotherapies. Due to the high rate of recurrence and rapid development of drug resistance, the current focus of research is on finding effective natural products with minimal toxic side effects for treating epithelial ovarian tumors. Cannabidiol is among the most abundant cannabinoids and has a non-psychoactive effect compared to tetrahydrocannabinol, which is a key advantage for clinical application...

Twelve new alkaloids, scolopenolines A-L ( 1 - 7 , 9 - 11 , 13 , 14 ), along with six known analogues, were isolated from Scolopendra subspinipes mutilans , identified by analysis of spectroscopic data and quantum chemical and computational methods. Scolopenoline A ( 1 ), a unique guanidyl-containing C14 quinoline alkaloid, features a 6/6/5 ring backbone. Scolopenoline B ( 2 ) is a novel sulfonyl-containing heterodimer comprising quinoline and tyramine moieties. Scolopenoline G ( 7 ) presents a rare C12 quinoline skeleton with a 6/6/5 ring system...

Triterpenoids are a type of specialized metabolites that exhibit a wide range of biological activities. However, the availability of some minor triterpenoids in nature is limited, which has hindered our understanding of their pharmacological potential. To overcome this limitation, heterologous biosynthesis of triterpenoids in yeast has emerged as a promising and time-efficient production platform for obtaining these minor compounds. In this study, we analyzed the transcriptomic data of Enkianthus chinensis to identify one oxidosqualene cyclase ( EcOSC ) gene and four CYP716s...

Enhanced glucose uptake in insulin-sensitive tissues is one of the therapeutic strategies to ameliorate hyperglycemia and maintain glucose homeostasis in type 2 diabetes. This study disclosed the role of fungal depsidones in glucose uptake and the underlying mechanism in 3T3-L1 adipocytes. Depsidones, including nidulin, nornidulin, and unguinol, isolated from Aspergillus unguis , stimulate glucose uptake in adipocytes. Compared to the others, nidulin exhibited an upward trend in glucose uptake. The effect of nidulin was found to be dose- and time-dependent...

Cinnamoyl moiety containing nonribosomal peptides represented by pepticinnamin E are a growing family of natural products isolated from different Streptomyces species and possess diverse bioactivities. The soil bacterium Streptomyces mirabilis P8-A2 harbors a cryptic pepticinnamin biosynthetic gene cluster, producing azodyrecins as major products. Inactivation of the azodyrecin biosynthetic gene cluster by CRISPR-BEST base editing led to the activation and production of pepticinnamin E ( 1 ) and its analogues, pepticinnamins N, O, and P ( 2 - 4 ), the structures of which were determined by detailed NMR spectroscopy, HRMS data, and Marfey's reactions...

Fungal 10-membered lactones (TMLs), such as stagonolide A, herbarumin I, pinolidoxin, and putaminoxin, are promising candidates for the development of nature-derived herbicides. The aim of this study was to analyze the structure-activity relationships (SAR) of C-9-methyl-substituted TMLs with a multitarget bioassay approach to reveal compounds with useful (phytotoxic, entomotoxic, antimicrobial) or undesirable (cytotoxic) bioactivities. A new TML, stagonolide L ( 1 ), along with five known compounds (stagonolides D ( 2 ) and E ( 3 ), curvulides A ( 4 ) and B1 /B2 ( 5a , b ), and pyrenolide C ( 6 )), were purified from cultures of the phytopathogenic fungus Stagonospora cirsii , and five semisynthetic derivatives of 3 and 4 ( 7 - 11 ) were obtained...

A chemical investigation of the hydrophilic fraction of a cultured Nodularia sp. (NIES-3585) afforded six new cyclic lipopeptides, noducyclamides A1-A4 ( 1 - 4 ) containing 10 amino acid residues and dodecapeptides noducyclamides B1 and B2 ( 5 and 6 ). The planar structures of these lipopeptides were elucidated based on the combination of HRMS and 1D and 2D NMR spectroscopic data analyses. These peptides are structurally analogous to laxaphycins and contain the nonproteinogenic amino acids 3-hydroxyvaline and 3-hydroxyleucine and a β-amino decanoic acid residue...

Three new ( 1 - 3 ) and six known rotenoids ( 5 - 10 ), along with three known isoflavones ( 11 - 13 ), were isolated from the leaves of Millettia oblata ssp. teitensis . A new glycosylated isoflavone ( 4 ), four known isoflavones ( 14 - 18 ), and one known chalcone ( 19 ) were isolated from the root wood extract of the same plant. The structures were elucidated by NMR and mass spectrometric analyses. The absolute configuration of the chiral compounds was established by a comparison of experimental ECD and VCD data with those calculated for the possible stereoisomers...

We report on the use of <u>n</u>itric <u>o</u>xide-<u>me</u>diated <u>t</u>ranscriptional <u>a</u>ctivation (NOMETA) as an innovative means to detect and access new classes of microbial natural products encoded within silent biosynthetic gene clusters. A small library of termite nest- and mangrove-derived fungi and actinomyces was subjected to cultivation profiling using a miniaturized 24-well format approach (MATRIX) in the presence and absence of nitric oxide, with the resulting metabolomes subjected to comparative chemical analysis using UPLC-DAD and GNPS molecular networking...

Nine bacteria were isolated from the episphere of Suaeda maritima (L.) Dumort. Among them, the bacterial strain YSL2 displayed the highest antimicrobial activity on agar plates and exhibited significant novelty compared with other bacteria based on 16S rRNA analysis. Consequently, Nocardiopsis maritima YSL2T was subjected to phenotypic characterization and whole-genome sequencing. Phylogenetic analysis revealed its close association with Nocardiopsis aegyptia SNG49T . Furthermore, genomic analysis of strain YSL2T revealed the presence of various gene clusters, indicating its potential for producing antimicrobial secondary metabolites...

Seven new sugar alcohol-conjugated acyclic sesquiterpenes, acremosides A-G ( 1 - 7 ), were isolated from the cultures of the sponge-associated fungus Acremonium sp. IMB18-086 cultivated with heat-killed Pseudomonas aeruginosa . The structures were determined by comprehensive analyses of 1D and 2D NMR spectroscopic data. The relative configurations were established by J -based configuration analysis and acetonide derivatization. The absolute configurations were elucidated by the Mosher ester method and ECD calculations...

As an important bioactive molecular backbone, drimane meroterpenoids have drawn a great deal of attention from both pharmacologists and chemists. Inspired by the prevalidated success of conformational restriction in the discovery of novel pharmaceutical leads, two distinct tetracyclic drimane meroterpenoids, (-)-pelorol and (+)-aureol, were synthesized from the inexpensive starting material (-)-sclareol through 10 and 8 steps with 5.6% and 5.4% overall yield, respectively. The mild conditions, operational facility, and scalability enabled the expedient synthesis and biological exploration of not only natural products themselves but also their mimics...