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1.
Bioorg Med Chem ; 103: 117685, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38503009

ABSTRACT

Genome sequencing on an intertidal zone-derived Aspergillus flavipes strain revealed its great potential to produce secondary metabolites. To activate the cryptic compounds of A. flavipes, the global regulator flLaeA was knocked out, leading to substantial up-regulation of the expression of two NRPS-like biosynthetic gene clusters in the ΔflLaeA mutant. With a scaled-up fermentation of the ΔflLaeA strain, five compounds, including two previously undescribed piperazine derivatives flavipamides A and B (1 and 2), along with three known compounds (3-5), were obtained by LC-MS guided isolation. The new compounds were elucidated by spectroscopic analysis and electronic circular dichroism (ECD) calculations, and the biosynthetic pathway was proposed on the bias of bioinformatic analysis and 13C isotope labeling evidence. This is the first report to access cryptic fungi secondary metabolites by inactivating global regulator LaeA and may provide a new approach to discovering new secondary metabolites by such genetic manipulation.


Subject(s)
Aspergillus , Fungi , Aspergillus/genetics , Aspergillus/metabolism , Piperazines/pharmacology , Piperazines/metabolism
2.
Neuroradiology ; 66(3): 443-455, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38183426

ABSTRACT

BACKGROUND: Optimal lumbar puncture segment selection remains controversial. This study aims to analyze anatomical differences among L3-4, L4-5, and L5-S1 segments across age groups and provide quantitative evidence for optimized selection. METHODS: 80 cases of CT images were collected with patients aged 10-80 years old. Threedimensional models containing L3-S1 vertebrae, dural sac, and nerve roots were reconstructed. Computer simulation determined the optimal puncture angles for the L3-4, L4-5, and L5-S1 segments. The effective dural sac area (ALDS), traversing nerve root area (ATNR), and area of the lumbar inter-laminar space (ALILS) were measured. Puncture efficacy ratio (ALDS/ALILS) and nerve injury risk ratio (ATNR/ALILS) were calculated. Cases were divided into four groups: A (10-20 years), B (21-40 years), C (41-60 years), and D (61-80 years). Statistical analysis was performed using SPSS. RESULTS: 1) ALDS was similar among segments; 2) ATNR was greatest at L5-S1; 3) ALILS was greatest at L5-S1; 4) Puncture efficacy ratio was highest at L3-4 and lowest at L5-S1; 5) Nerve injury risk was highest at L5-S1. In group D, L5-S1 ALDS was larger than L3-4 and L4-5. ALDS decreased after age 40. Age variations were minimal across parameters. CONCLUSION: The comprehensive analysis demonstrated L3-4 as the optimal first-choice segment for ages 10-60 years, conferring maximal efficacy and safety. L5-S1 can serve as an alternative option for ages 61-80 years when upper interspaces narrow. This study provides quantitative imaging evidence supporting age-specific, optimized lumbar puncture segment selection.


Subject(s)
Lumbar Vertebrae , Spinal Puncture , Humans , Child , Adolescent , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Computer Simulation , Lumbar Vertebrae/diagnostic imaging , Lumbosacral Region , Tomography, X-Ray Computed
3.
J Nat Prod ; 87(5): 1401-1406, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38634860

ABSTRACT

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. In vitro studies demonstrated that 1 exerted significant inhibition of NF-κB activation in the classical pathway by preventing TAK1 activation, IκBα phosphorylation, and p65 translocation. Furthermore, 1 effectively reduced the level of NFATc1 activation, resulting in the attenuation of osteoclast differentiation. Our findings suggest that 1 holds promise as an inhibitor with significant potential for the treatment of diseases related to osteoporosis.


Subject(s)
Cell Differentiation , Diterpenes , Indoles , NF-kappa B , Osteoclasts , Penicillium , Penicillium/chemistry , Osteoclasts/drug effects , Diterpenes/pharmacology , Diterpenes/chemistry , Diterpenes/isolation & purification , Animals , Mice , Cell Differentiation/drug effects , Molecular Structure , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Indoles/pharmacology , Indoles/chemistry , RANK Ligand/pharmacology , Lipopolysaccharides/pharmacology , Macrophages/drug effects
4.
J Nat Prod ; 87(4): 753-763, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38372239

ABSTRACT

In this study, we isolated lovastatin derivatives, including aculeatiols A-G (1-7) and three known compounds (8-10), from Aspergillus aculeatus. Their structures and absolute configurations were experimentally determined by high-resolution electrospray ionization mass spectrometry, nuclear magnetic resonance spectroscopy, and X-ray diffraction analyses, and the results were corroborated by quantum-chemical calculations. As members of the lovastatin derivatives, aculeatiols A-C (1-3) possess a γ-lactone functional group in the side chain. Compound 6 represents the first example that features an undescribed aromatized heterotetracyclic 6/6/6/6 ring system. Biologically, the lipid-lowering effects of all of these compounds were evaluated by analyzing the free fatty acid-induced intracellular lipid accumulation. In addition, compound 5, which regulated the transcription of genes associated with lipid uptake and synthesis, inhibited the accumulation of lipids.


Subject(s)
Aspergillus , Lovastatin , Aspergillus/chemistry , Lovastatin/pharmacology , Lovastatin/chemistry , Molecular Structure , Humans
5.
J Nat Prod ; 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38943602

ABSTRACT

Four new p-terphenyl derivatives, talaroterphenyls A-D (1-4), together with three biosynthetically related known ones (5-7), were obtained from the mangrove sediment-derived Talaromyces sp. SCSIO 41412. Compounds 1-3 are rare p-terphenyls, which are completely substituted on the central benzene ring by oxygen atoms; this is the first report of their isolation from natural sources. Their structures were elucidated through NMR spectroscopy, HRESIMS, and X-ray diffraction. Genome sequence analysis revealed that 1-7 were biosynthesized from tyrosine and phenylalanine, involving four key biosynthetic genes (ttpB-ttpE). These p-terphenyls (1-7) and 36 marine-derived terphenyl analogues (8-43) were screened for phosphodiesterase 4 (PDE4) inhibitory activities, and 1-5, 14, 17, 23, and 26 showed notable activities with IC50 values of 0.40-16 µM. The binding pattern of p-terphenyl inhibitors 1-3 with PDE4 were explored by molecular docking analysis. Talaroterphenyl A (1), with a low cytotoxicity, showed obvious anti-inflammatory activity in LPS-stimulated RAW264.7 cells. Furthermore, in the TGF-ß1-induced medical research council cell strain-5 (MRC-5) pulmonary fibrosis model, 1 could down-regulate the expression levels of FN1, COL1, and α-SMA significantly at concentrations of 5-20 µM. This study suggests that the oxidized p-terphenyl 1, as a marine-derived PDE4 inhibitor, could be used as a promising antifibrotic agent.

6.
Bioorg Chem ; 146: 107280, 2024 May.
Article in English | MEDLINE | ID: mdl-38479131

ABSTRACT

Ten new compounds, including three pairs of diarylcyclopentenone enantiomers (±) talaromycesins A-C (1-3) and four biphenyl derivatives talaromycesins D-G (4-7), along with four known compounds (8-11), were isolated from the fungus Talaromyces adpressus. Their structures were determined by analyses of extensive NMR spectroscopic and HRESIMS data, and their absolute configurations were elucidated by the dimolybdenum tetraacetate [Mo2(AcO)4]-induced ECD spectra, X-ray crystallographic studies, and ECD calculations. These new compounds were evaluated for their immunosuppressive activities for the first time, and compound 7 probably exerted liver-protective and anti-inflammatory effects on Con A-induced AIH by decreasing the levels of inflammatory cytokines, modulating immune homeostasis, and decreasing hepatocyte apoptosis, which may become a potential drug for the treatment of autoimmune diseases.


Subject(s)
Talaromyces , Magnetic Resonance Spectroscopy , Talaromyces/chemistry , Biphenyl Compounds , Molecular Structure
7.
Mar Drugs ; 22(3)2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38535444

ABSTRACT

Two new sesquiterpenoid derivatives, elgonenes M (1) and N (2), and a new shikimic acid metabolite, methyl 5-O-acetyl-5-epi-shikimate (3), were isolated from the mangrove sediment-derived fungus Roussoella sp. SCSIO 41427 together with fourteen known compounds (4-17). The planar structures were elucidated through nuclear magnetic resonance (NMR) and mass spectroscopic (MS) analyses. The relative configurations of 1-3 were ascertained by NOESY experiments, while their absolute configurations were determined by electronic circular dichroism (ECD) calculation. Elgonene M (1) exhibited inhibition of interleukin-1ß (IL-1ß) mRNA, a pro-inflammatory cytokine, at a concentration of 5 µM, with an inhibitory ratio of 31.14%. On the other hand, elgonene N (2) demonstrated inhibition at a concentration of 20 µM, with inhibitory ratios of 27.57%.


Subject(s)
Ascomycota , Sesquiterpenes , Shikimic Acid/analogs & derivatives , Circular Dichroism
8.
Article in English | MEDLINE | ID: mdl-38733533

ABSTRACT

BACKGROUND: Advancements in nasopharyngeal carcinoma (NPC) treatment have led to a focus on personalized treatment. Circulating tumor cells (CTCs) are important for liquid biopsies and personalized treatment but are not being fully utilized. This study examined how pre- and post-treatment CTC counts, EMT subtypes, clinical characteristics, and patient prognosis are related in order to support the use of liquid biopsy in managing NPC. METHODS: This retrospective study included 141 patients with locally advanced NPC. All patients underwent CanPatrol™ CTC detection pre- and post-treatment and were categorized into EMT subtypes: epithelial type, mixed type, and mesenchymal type. This study analyzed CTC enumeration, EMT subtypes, and their associations with clinical characteristics and survival outcomes. RESULTS: The results indicated a positive correlation between the pre-treatment detection rate of CTCs and N stage (P < 0.01), alongside a positive correlation with the TNM clinical stage (P = 0.02). Additionally, the detection rate of mesenchymal CTCs post-treatment is positively associated with the N stage (P = 0.02). The enumeration of CTCs pre- and post-treatment is negatively correlated with prognosis and has statistical significance. Additionally, an investigation into the EMT subtypes of CTCs revealed a significant association between the presence of mesenchymal CTCs pre- and post-treatment and decreased overall survival (OS) (P < 0.05). Furthermore, T stage, N stage, TNM clinical stage, and Epstein-Barr virus (EBV) DNA were also significantly correlated with OS. CONCLUSION: The study found that mesenchymal CTCs pre- and post-treatment, as well as the number of CTCs, were linked to a poor prognosis.

9.
Chem Biodivers ; 21(4): e202400070, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38356321

ABSTRACT

One new fatty acid derivative, (2E,4E)-6,7-dihydroxy-2-methylocta-2,4-dienoic acid (1), and 16 known compounds (2-17) were isolated from the mangrove sediment derived fungus Trichoderma harzianum SCSIO 41051. Their structures were established by spectroscopic methods, computational ECD, and Mo2(OAc)4-induced ECD experiment. All the compounds were evaluated for their acetylcholinesterase (AChE) and pancreatic lipase (PL) inhibition. Compounds 9 and 14 exhibited moderate AChE inhibitory activities with IC50 values of 2.49 and 2.92 µM, respectively, which compounds 8 and 9 displayed moderate inhibition on PL with IC50 value of 2.30 and 2.34 µM, respectively.


Subject(s)
Hypocreales , Trichoderma , Acetylcholinesterase/metabolism , Enzyme Inhibitors/pharmacology , Hypocreales/chemistry , Molecular Structure , Trichoderma/chemistry , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/isolation & purification , Cholinesterase Inhibitors/pharmacology , Lipase/antagonists & inhibitors
10.
J Craniofac Surg ; 2024 May 17.
Article in English | MEDLINE | ID: mdl-38758565

ABSTRACT

OBJECTIVE: To study the efficacy of ultrasound-guided parasternal block (US-PSI) in pediatric patients undergoing auricular reconstruction surgery. METHODS: For this study, the authors recruited 60 children between the ages of 5 and 12 years who underwent auricular reconstruction with autologous costal cartilage (ACC) to correct microtia. They were randomized to receive either ultrasound-guided modified parasternal block or periprostatic local infiltration anesthesia (PLIA), with 30 cases in each group. Ultrasound-guided parasternal block was administered following anesthesia induction, whereas PLIA was administered after ACC harvest. Lastly, following surgery, all children were provided with patient-controlled intravenous analgesia with sufentanil, and the numeric pain rating scale (NRS) was used to assess the intensity of pain. Our primary outcomes were the resting NRS pain scores and the NRS scores upon coughing at 1, 6, 12, 24, and 48 hours postsurgery. Sufentanil consumption within the first 24 hours of surgery, the mean duration to first ambulation, and the usage of rescue analgesics were our secondary outcomes. The authors also recorded the occurrence of undesirable side effects as well as more serious side effects like pneumothorax. RESULTS: Pediatric patients who were administered US-PSI showed significantly reduced NRS chest pain scores at 6 and 12 hours postsurgery compared to those who received PLIA (P<0.05). In addition, sufentanil consumption within the first 24 hours postsurgery, duration to first ambulation, and use of rescue analgesics were significantly lower among patients in the US-PSI group when compared to those in the PLIA group (P<0.05). CONCLUSIONS: This study found that US-PSI was a highly efficacious and safe technique for postsurgical analgesia following auricular reconstruction with ACC in pediatric patients. LEVEL OF EVIDENCE: Level II, therapeutic study.

11.
Aesthetic Plast Surg ; 48(9): 1846-1854, 2024 May.
Article in English | MEDLINE | ID: mdl-38326498

ABSTRACT

PURPOSE: Pain following costal cartilage harvest surgery is the most common complaint of auricular reconstruction (AR). Anesthesiologists are continuously searching for an effective postoperative pain control method. METHODS: This study was conducted from 10 April 2022 to 10 June 2022. Sixty children undergoing AR using costal cartilage were randomly assigned to either a serratus anterior plane block performed before costal cartilage harvest (SAPB-pre-cohort; n = 30) or the SAPB-post-cohort (Post-costal cartilage Harvest Cohort: n = 30). The primary endpoint measures were the Numerical Rating Scale (NRS) scores of the chest and ear pain degrees recorded at 1-, 6-, 12-, 24-, and 48-h after surgery. Intraoperative anesthetic and analgesic dosages, sufentanil consumption and rescue analgesia consumption during the first 24 h post-operation, cough score during extubation, extubation agitation score, length of stay, the extubation time, first ambulatory time, analgesia duration, and opioid-related adverse effects and SAPB-related adverse effects were the secondary endpoints. RESULTS: The rest and coughing NRS scores were significantly reduced in the SAPB-pre-cohort 6 and 12 h post-operation in comparison with the SAPB-post-cohort (rest 6 h p = 0.002, others p < 0.001). No significant difference in the NRS ear scores existed between the two cohorts (p > 0.05). The use of propofol and remifentanil for general anesthesia during the SAPB-pre-procedure was significantly reduced compared to the SAPB-post-group, with statistical significance (p < 0.001). Sufentanil consumption and rescue analgesia consumption were significantly reduced in the SAPB-pre-cohort (p = 0.001, p = 0.033). The extubation time and first ambulatory time were markedly shorter in the SAPB-pre-cohort (all p < 0.001). Analgesia duration was markedly longer in the SAPB-pre-cohort (p < 0.001). No significant differences were noted in the cough score during extubation, extubation agitation score, length of stay between the two cohorts (all p > 0.05). Opioid-related adverse effects occurred more in the SAPB-post-cohort, while there was no statistical significance (16.7 vs. 36.7%; p = 0.082). There were no blockade-related complications observed in either cohort. CONCLUSION: The analgesic effect of the SAPB-pre-cohort was better than the SAPB-post-cohort suggesting both efficacy and feasibility of preemptive analgesia. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Subject(s)
Congenital Microtia , Costal Cartilage , Nerve Block , Pain, Postoperative , Plastic Surgery Procedures , Ultrasonography, Interventional , Humans , Male , Female , Child , Pain, Postoperative/prevention & control , Congenital Microtia/surgery , Nerve Block/methods , Plastic Surgery Procedures/methods , Costal Cartilage/transplantation , Pain Measurement , Adolescent , Cohort Studies
12.
J Sci Food Agric ; 104(2): 1039-1050, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-37743412

ABSTRACT

BACKGROUND: Withering is the first processing procedure of beauty tea, and there are few reports on the impact of withering methods on the quality of beauty tea and its regulatory mechanisms. RESULTS: Through comparison of fresh tea leaves (FT) with the leaves after indoor natural withering for 18 h (IWT-18) and outdoor solar withering for 6 h (OWT-6), which were collected at the end of the two withering processes, 17 282 and 13 984 differentially expressed genes (DEGs) were respectively screened and 267 and 154 differential metabolites (DMs) were respectively identified. The coexpression network revealed that a large number of DEGs and DMs were enriched in phenylpropanoid, flavonoid, and adenosine triphosphate binding cassette (ABC) transporter pathways, and the number of DMs and DEGs in IWT-18 versus FT exceeded that in OWT-6 versus FT. Both withering methods promoted a significant increase in content of phenylalanine and upregulation of ß-glucoside expression in the phenylpropanoid metabolism pathway. Five theaflavin-type proanthocyanidins in the flavonoid synthesis pathway were more significantly accumulated in FT versus IWT-18 than in FT versus OWT-6. Meanwhile, both withering methods can affect the ABC transporter pathway to promote the accumulation of amino acids and their derivatives, but different withering methods affect different ABC transporter families. Outdoor withering with more severe abiotic stress has a greater impact on the ABCG family, whereas indoor withering has a more significant effect on the ABCC family. Sensory evaluation results showed that the dry tea of IWT-18 was slightly better than that of OWT-6 because of the longer withering time and more thorough substance transformation. CONCLUSION: In conclusion, the formation of honey flavor in beauty tea may be closely related to the DEGs and DMs in these three pathways. Our research provides theoretical data support for further revealing the mechanism of quality formation during the withering process of beauty tea. © 2023 Society of Chemical Industry.


Subject(s)
Camellia sinensis , Camellia sinensis/chemistry , Transcriptome , Beauty , Metabolome , Flavonoids/analysis , Tea/chemistry , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/analysis , ATP-Binding Cassette Transporters/metabolism , Plant Leaves/chemistry
13.
Ophthalmology ; 130(5): 542-550, 2023 05.
Article in English | MEDLINE | ID: mdl-36642334

ABSTRACT

PURPOSE: Defocus incorporated multiple segments (DIMS) spectacle lenses were reported to slow myopia progression significantly in a randomized controlled trial (RCT). The study evaluated their effectiveness in clinical settings. DESIGN: Retrospective study. PARTICIPANTS: Patient records involving use of DIMS and single-vision (SV) spectacle lenses were collected from subsidiary hospitals of Aier Eye Hospital Group. METHODS: The spherical equivalent (SE), determined by subjective refraction, was adopted to assess the myopia progression. The strategy of propensity score matching (PSM) was applied to match the confounding baseline characteristics between the 2 groups. The effectiveness was calculated based on the difference of myopia progression of these 2 approaches. MAIN OUTCOME MEASURES: Change in SE. RESULTS: Three thousand six hundred thirty-nine patients with DIMS and 6838 patients with SV spectacles were included. The age of the patients was 6 to 16 years (mean ± standard deviation: 11.02 ± 2.53 years). The baseline SE was between 0.00 and -10.00 diopters (D) (mean ± standard deviation: -2.78 ± 1.74 D). After the PSM, data on 2240 pairs with 1-year follow-up and on 735 pairs with 2-year follow-up were obtained. Significantly slower progression was seen in the DIMS group at both the 1-year (DIMS, -0.50 ± 0.43 D; SV, -0.77 ± 0.58 D; P < 0.001) and 2-year (DIMS, -0.88 ± 0.62 D; SV, -1.23 ± 0.76 D; P < 0.001) subdataset. In the 1-year subdataset, 40% and 19% showed myopia progression of no more than 0.25 D for the DIMS and SV groups, respectively (chi-square, 223.43; P < 0.001), whereas 9% and 22% showed myopia progression of more than 1.00 D for the DIMS and SV groups, respectively (chi-square, 163.38; P < 0.001). In the 2-year subdataset, 33% and 20% showed myopia progression of no more than 0.50 D for the DIMS and SV groups, respectively (chi-square, 31.15; P < 0.001), whereas 12% and 29% showed myopia progression of more than 1.50 D for the DIMS and SV groups (chi-square, 65.60; P < 0.001). CONCLUSIONS: Although the magnitude was lower than that reported in the previous RCT, this large-scale study with diversity of the data sources confirmed the effectiveness of DIMS spectacles to slow myopia progression in clinical practice. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.


Subject(s)
Myopia , Humans , Child , Adolescent , Myopia/therapy , Refraction, Ocular , Eyeglasses , Disease Progression , Face
14.
Br J Clin Pharmacol ; 89(1): 253-260, 2023 01.
Article in English | MEDLINE | ID: mdl-35971682

ABSTRACT

AIMS: The aim of this study was to identify factors associated with gastrointestinal bleeding (GIB) in patients on direct oral anticoagulants (DOACs) and develop a risk score that would provide an effective tool for the clinical assessment of GIB. METHODS: This was a multicentre retrospective analysis of clinical and follow-up data of patients treated with DOACs. The score was developed through logistic regression. The performance of score was evaluated using the area under the receiver operating characteristic curve (AUC), sensitivity, specificity and Hosmer-Lemeshow test. RESULTS: The 11 903 patients had a mean age of 65.1 years. In multivariate analysis, age ≥65 years, alcohol use, history of peptic ulcer, history of major bleeding, abnormal liver function or renal function, cancer, platelet count <100 × 109 /L, anaemia, and concurrent antiplatelet agent or non-steroidal anti-inflammatory drug treatment were independent risk factors for GIB, and concurrent treatment with gastrointestinal protective agents were a protective factor. The Alfalfa-DOAC-GIB score was constructed using these 12 factors. The AUC of the Alfalfa-DOAC-GIB score was 0.77 (95% CI 0.74-0.81), which was higher than that of the HAS-BLED score (0.69; 95% CI 0.65-0.72) and the New score (0.65; 95% CI 0.61-0.68). CONCLUSIONS: Based on 12 factors, we developed a gastrointestinal bleeding risk score. The newly developed Alfalfa-DOAC-GIB score has better predictive value than the HAS-BLED score and the New score, and might be an effective tool to help reduce the occurrence of GIB in patients using DOACs.


Subject(s)
Atrial Fibrillation , Rivaroxaban , Humans , Aged , Rivaroxaban/adverse effects , Dabigatran/adverse effects , Anticoagulants/adverse effects , Retrospective Studies , Gastrointestinal Hemorrhage/epidemiology , Gastrointestinal Agents , Administration, Oral , Atrial Fibrillation/drug therapy
15.
J Org Chem ; 88(4): 2393-2403, 2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36715636

ABSTRACT

A novel and convenient K2S2O8-mediated diiodo cyclization of 1,6-enynes for the facile synthesis of functionalized γ-lactam derivatives has been developed. This reaction features mild and transition-metal-free conditions, which offer a green and efficient entry to synthetically important γ-lactam scaffolds. Mechanistic studies suggest that iodide radicals initiate the cascade cyclic transformation.

16.
Org Biomol Chem ; 21(10): 2236-2242, 2023 03 08.
Article in English | MEDLINE | ID: mdl-36815264

ABSTRACT

Fumitryprostatin A (1), the first example of an indole diketopiperazine alkaloid with a tricyclic 5/6/5 skeleton characterized by a dipyrrolo[1,2-a:1',2'-d]pyrazine-5,10-dione ring system decorated with a prenylated indole moiety, and fuminoid A (2), a sesquiterpenoid with a bicyclo[3.2.1]octane ring featuring a novel carbon skeleton via the transformation of the methyl, were isolated from the fungus Aspergillus fumigatus along with six known diketopiperazine alkaloids. The structure with the absolute configuration of 1 was determined based on spectroscopic analyses and X-ray crystallographic analysis, while the configuration of 2 was assigned tentatively by 13C NMR data with DP4+ probability analyses and ECD calculations. A plausible biosynthetic pathway for 1 was proposed starting from L-Trp and L-Pro via normal indole diketopiperazine. Compound 1 exhibited moderate cytotoxic activity with an IC50 value of 14.6 µM, while compound 8 exhibited moderate immunosuppressive activity in vitro.


Subject(s)
Alkaloids , Sesquiterpenes , Aspergillus fumigatus , Monocyclic Sesquiterpenes , Diketopiperazines/pharmacology , Diketopiperazines/chemistry , Indole Alkaloids/pharmacology , Indole Alkaloids/chemistry , Alkaloids/pharmacology , Alkaloids/chemistry , Magnetic Resonance Spectroscopy , Sesquiterpenes/pharmacology
17.
Environ Sci Technol ; 57(29): 10696-10707, 2023 07 25.
Article in English | MEDLINE | ID: mdl-37449758

ABSTRACT

Despite substantial experimental evidence of electron transfer, atom exchange, and mineralogical transformation during the reaction of Fe(II)aq with synthetic Fe(III) minerals, these processes are rarely investigated in natural soils. Here, we used an enriched Fe isotope approach and Mössbauer spectroscopy to evaluate how soil organic matter (OM) influences Fe(II)/Fe(III) electron transfer and atom exchange in surface soils collected from Luquillo and Calhoun Experimental Forests and how this reaction might affect Fe mineral composition. Following the reaction of 57Fe-enriched Fe(II)aq with soils for 33 days, Mössbauer spectra demonstrated marked electron transfer between sorbed Fe(II) and the underlying Fe(III) oxides in soils. Comparing the untreated and OM-removed soils indicates that soil OM largely attenuated Fe(II)/Fe(III) electron transfer in goethite, whereas electron transfer to ferrihydrite was unaffected. Soil OM also reduced the extent of Fe atom exchange. Following reaction with Fe(II)aq for 33 days, no measurable mineralogical changes were found for the Calhoun soils enriched with high-crystallinity goethite, while Fe(II) did drive an increase in Fe oxide crystallinity in OM-removed LCZO soils having low-crystallinity ferrihydrite and goethite. However, the presence of soil OM largely inhibited Fe(II)-catalyzed increases in Fe mineral crystallinity in the LCZO soil. Fe atom exchange appears to be commonplace in soils exposed to anoxic conditions, but its resulting Fe(II)-induced recrystallization and mineral transformation depend strongly on soil OM content and the existing soil Fe phases.


Subject(s)
Ferric Compounds , Iron , Iron/chemistry , Ferric Compounds/chemistry , Soil , Electrons , Oxidation-Reduction , Minerals/chemistry , Oxides , Ferrous Compounds
18.
J Nat Prod ; 86(5): 1171-1178, 2023 05 26.
Article in English | MEDLINE | ID: mdl-36726314

ABSTRACT

Seven new tanzawaic acid derivatives, steckwaic acids E-K (1-7), and one new benzene derivate (8), together with seven known tanzawaic acid analogues (9-16) were isolated from the marine algicolous fungus Penicillium steckii SCSIO 41040. The structures and absolute configurations of these new compounds (1-8) were determined by spectroscopic analyses, X-ray diffraction, and comparison of ECD spectra to calculations. Compounds 2, 10, and 15 inhibited lipopolysaccharide (LPS)-induced nuclear factor kappa-B (NF-κB) with IC50 values of 10.4, 18.6, and 15.2 µM, respectively. Compound 2 could suppress the receptor activator of NF-κB ligand (RANKL)-induced osteoclast differentiation in bone marrow macrophage cells (BMMCs). To the best of our knowledge, this is the first report of osteoclastogenesis inhibitory activity for tanzawaic acid derivatives.


Subject(s)
Osteogenesis , Penicillium , Cell Differentiation , Macrophages , NF-kappa B , Osteoclasts , Penicillium/chemistry , RANK Ligand/pharmacology , Polyketides/chemistry , Polyketides/pharmacology
19.
J Nat Prod ; 86(7): 1643-1653, 2023 07 28.
Article in English | MEDLINE | ID: mdl-37449914

ABSTRACT

Twelve new fungal polyketides, koningiopisins I-P (1-8) and trichoketides C-F (9-12), together with six known congeners (13-18), were isolated from Trichoderma koningiopsis, a rhizosphere fungus obtained from the medicinal plant Polygonum paleaceum. Their structures and absolute configurations were established by spectroscopic analysis, single-crystal X-ray diffraction, the modified Mosher's method, chemical derivatization, the octant rule, and 13C NMR and ECD calculations. Compounds 1-5 are tricyclic polyketides possessing an octahydrochromene framework with a 6,8-dioxabicyclo[3.2.1]octane core. Compounds 7 and 8 contain a unique ketone carbonyl group at C-7 and differ from other members of this group of compounds with the ketone carbonyl group at C-1. Compounds 1, 2, and 13 showed inhibitory activity on LPS-induced BV-2 cells on NO production with IC50 values of 14 ± 1, 3.0 ± 0.5, and 8.9 ± 2.7 µM, respectively.


Subject(s)
Plants, Medicinal , Polygonum , Polyketides , Polyketides/chemistry , Rhizosphere , Molecular Structure , Magnetic Resonance Spectroscopy , Fungi
20.
J Nat Prod ; 86(9): 2081-2090, 2023 09 22.
Article in English | MEDLINE | ID: mdl-37676247

ABSTRACT

Nine new ergosteroids (1-9) and seven known ones (10-16) were isolated from Talaromyces adpressus. Their structures and absolute configurations were determined by the interpretation of NMR spectroscopic data, HRESIMS, ECD calculations, and single-crystal X-ray diffraction analyses. Structurally, compound 1 was an ergosteroid with two epoxy and a 3α-OH group at ring A, while compounds 8 and 9 had a contracted ring A with a peroxy bridge between C-3 and C-9, which were reported for the first time. Compounds 2-6, 9, 11, and 15 displayed cytotoxic activities with IC50 values ranging from 0.4 to 32 µM, and compound 7 exhibited an immunosuppressive effect against LPS-induced B lymphocyte proliferation with an IC50 value of 8.6 µM. The structure-activity relationships of these compounds are briefly discussed.


Subject(s)
Antineoplastic Agents , Talaromyces , Cell Proliferation , Crystallography, X-Ray
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