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1.
Front Chem ; 10: 860795, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464233

RESUMO

Synthesis of zeolites in more efficient and greener methods is of great significance in both industrial and academic fields. However, the relative long time for zeolite crystallization and much consumption of water solvent make the target challengeable. Herein, a route for ultrafast synthesis of nano Silicalite-1 zeolites in 10 min with much less water consumption has been developed. Comprehensive characterizations, i.e., X-ray powder diffraction, N2 sorption, scanning electron microscope, and NMR, confirm the high quality of such obtained Silicalite-1 zeolites. In the catalytic deoxygenation of O2-containing ethylene (mixture of O2 and ethylene), these reported Silicalite-1 zeolite samples show the comparable performance with the conventional Silicalite-1 zeolites synthesized under hydrothermal conditions. This research therefore provides a new trial toward the ultrafast synthesis of zeolite materials in an environment-friendly route.

2.
Org Lett ; 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35476540

RESUMO

Four new macrolides, kongjuemycins A and B1-B3 (1-4), were isolated from a coral-associated actinomycete Pseudonocardia kongjuensis SCSIO 11457. Their structures were characterized by comprehensive spectroscopic analysis and single-crystal X-ray diffraction. The absolute configurations of 1 and 2 were established by electronic circular dichroism calculation and the modified Mosher's method. Kongjuemycins displayed antifungal activity against three phytopathogenic fungi.

3.
BMC Anesthesiol ; 22(1): 22, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35026992

RESUMO

BACKGROUND: Postoperative acute kidney injury (AKI) is associated with poor clinical outcomes. Early identification of high-risk patients of developing postoperative AKI can optimize perioperative renal management and facilitate patient survival. The present study aims to develop and validate a nomogram to predict postoperative AKI after liver resection in older patients. METHODS: A retrospective observational study was conducted involving data from 843 older patients scheduled for liver resection at a single tertiary high caseload general hospital between 2012 and 2019. The data were randomly divided into training (70%, n = 599) and validation (30%, n = 244) datasets. The training cohort was used to construct a predictive nomogram for postoperative AKI with the logistic regression model which was confirmed by a validation cohort. The model was evaluated by receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis in the validation cohort. A summary risk score was also constructed for identifying postoperative AKI patients. RESULTS: Postoperative AKI occurred in 155 (18.4%) patients and was highly associated with in-hospital mortality (5.2% vs. 0.7%, P <  0.001). The six predictors selected and assembled into the nomogram included age, preexisting chronic kidney disease (CKD), non-steroidal anti-inflammatory drugs (NSAIDs) usage, intraoperative hepatic inflow occlusion, blood loss, and transfusion. The predictive nomogram performed well in terms of discrimination with area under ROC curve (AUC) in training (0.73, 95% confidence interval (CI): 0.68-0.78) and validation (0.71, 95% CI: 0.63-0.80) datasets. The nomogram was well-calibrated with the Hosmer-Lemeshow chi-square value of 9.68 (P = 0.47). Decision curve analysis demonstrated a significant clinical benefit. The summary risk score calculated as the sum of points from the six variables (one point for each variable) performed as well as the nomogram in identifying the risk of AKI (AUC 0.71, 95% CI: 0.66-0.76). CONCLUSION: This nomogram and summary risk score accurately predicted postoperative AKI using six clinically accessible variables, with potential application in facilitating the optimized perioperative renal management in older patients undergoing liver resection. TRIAL REGISTRATION: NCT04922866 , retrospectively registered on clinicaltrials.gov on June 11, 2021.


Assuntos
Injúria Renal Aguda/epidemiologia , Fígado/cirurgia , Nomogramas , Complicações Pós-Operatórias/epidemiologia , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Projetos Piloto , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco
4.
mSystems ; 7(1): e0108421, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35014867

RESUMO

Periplasmic binding proteins such as ribose-binding proteins (RBPs) are involved in the bacterial chemotaxis two-component system. RBP selectively identifies and interacts with ribose to induce a conformational change that leads to chemotaxis. Here, we report the development of an engineered Escherichia coli (E. coli) strain expressing a redesigned RBP that can effectively sense cadmium ions and regulate chemotactic movement of cells toward a cadmium ion gradient. RBP was computationally redesigned to bind cadmium ions and produce the conformational change required for chemoreceptor binding. The successful design, CdRBP1, binds to cadmium ions with a dissociation constant of 268 nM. When CdRBP1 was expressed in the periplasmic space of E. coli, the bacteria became live cadmium ion hunters with high selectivity over other divalent metal ions. This work presents an example of making cadmium ions, which are toxic for most organisms, as an attractant to regulate cells movement. Our approach also demonstrates that RBP can be precisely designed to develop metal-detecting living systems for potential applications in synthetic biology and environmental studies. IMPORTANCE Cadmium pollution is one of the major environmental problems due to excessive release and accumulation. New technologies that can auto-detect cadmium ions with good biocompatibility are in urgent need. In this study, we engineered the bacterial chemotaxis system to positively sense cadmium ions by redesigning ribose-binding protein (RBP) to tightly bind cadmium ion and produce the right conformational change for receptor binding and signaling. Our engineered E. coli cells can auto-detect and chase cadmium ions with divalent metal ion selectivity. Many attempts have been carried out to redesign RBP at the ribose binding site with little success. Instead of the ribose binding site, we introduced the cadmium binding site in the opening of the ribose binding pocket by a specially developed computational algorithm. Our design strategy can be applied to engineer live bacteria with autonomous detection and remediation abilities for metal ions or other chemicals in the future.

5.
J Nat Prod ; 84(11): 2953-2960, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34787427

RESUMO

Penicisteckins A-D (1-4), two pairs of atropodiastereomeric biaryl-type hetero- and homodimeric bis-isochromans with 7,5'- and 7,7'-linkages and a pair of atropodiastereomeric 2-(isochroman-5-yl)-1,4-benzoquinone derivatives [penicisteckins E (5) and F (6)], were isolated from the Penicillium steckii HNNU-5B18. Their structures including the absolute configuration were determined by extensive spectroscopic and single-crystal X-ray diffraction analysis and TDDFT-ECD calculations. Both the bis-isochromans and the isochroman/1,4-benzoquinone conjugates represent novel biaryl scaffolds containing both central and axial chirality elements. The monomer anserinone B (8) exhibited potent antibacterial activities against Staphylococcus aureus ATCC 29213 and methicillin-resistant Staphylococcus aureus with minimal inhibition concentration values ranging from 2 to 8 µg mL-1. Plausible biosynthetic pathways of 1-6 are proposed, which suggest how the absolute configurations of the isolates were established during the biosynthetic scheme.


Assuntos
Antibacterianos/isolamento & purificação , Cromanos/isolamento & purificação , Penicillium/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Vias Biossintéticas , Cromanos/química , Cromanos/farmacologia , Staphylococcus aureus/efeitos dos fármacos
6.
Brain Behav ; 11(12): e32420, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34806823

RESUMO

INTRODUCTION: Postoperative delirium is one of the most common and dangerous psychiatric complications after hip surgery. The aim of this study was to investigate the incidence of postoperative delirium in elderly patients after hip fracture surgery and to identify risk factors for such, as part of developing a risk stratification index (RSI) system to predict a patient's risk of postoperative delirium. METHODS: Elderly patients (aged 65 years or older) with hip fractures who had received surgical treatment in our hospital between March 2018 and December 2019 were retrospectively included. Clinical data were collected, and multivariate logistic regression analysis was performed to investigate the relevant risk factors of postoperative delirium. An RSI system was developed based on factors identified in the regression analysis. RESULTS: Of 272 patients included, 52 (19.12%) experienced postoperative delirium. Drinking history (> 3/ week), the perioperative lactic acid level (Lac > 2 mmol/L), postoperative visual analog score (VAS) > 3, American Society of Anesthesiologists (ASA) physical status > II, application of the bispectral index, and preoperative diabetes were independent risk factors of postoperative delirium. When RSI ≥ 5, the rate of postoperative delirium significantly increased (p < .05). CONCLUSION: The RSI system developed here can safely guide postoperative outcomes of elderly patients with hip fractures, and RSI ≥ 5 may be able to predict the onset of postoperative delirium.


Assuntos
Delírio , Fraturas do Quadril , Idoso , Delírio/epidemiologia , Delírio/etiologia , Fraturas do Quadril/cirurgia , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
7.
Org Biomol Chem ; 19(41): 8940-8946, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34617948

RESUMO

Berninamycins are a class of thiopeptide antibiotics with potent activity against Gram-positive bacteria. Heterologous expression of the berninamycin (ber) biosynthetic gene cluster from marine-derived Streptomyces sp. SCSIO 11878 in different terrestrial model Streptomyces hosts led to the production of berninamycins A (1) and B (2) in Streptomyces lividans SBT18 and Streptomyces coelicolor M1154, while two new linearized berninamycins J (3) and K (4) were obtained in Streptomyces albus J1074. Their structures were elucidated by detailed interpretation of NMR data and Marfey's method. Bioactivity assays showed that the linear thiopeptides 3 and 4 were less potent than 1 and 2 in antibacterial activity. This work indicates that undefined host-dependent enzymes might be responsible for generating the linear thiopeptides 3 and 4 in S. albus J1074.


Assuntos
Antibacterianos
8.
Front Med (Lausanne) ; 8: 723191, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34595191

RESUMO

Background: Clonidine is an anesthetic with favorable efficacy and safety profiles for caudal epidural block, but comparisons with other adjuvants need to be confirmed in pediatric patients. Aim: To investigate the effects of clonidine as an adjuvant in caudal epidural block to improve the intraoperative and postoperative analgesia in pediatric surgery. Methods: PubMed, Embase, and the Cochrane Library were searched for available papers published up to February 2021. The outcomes were pain score, duration of analgesia, complications, and number of analgesic requirements. The meta-analysis was performed using random-effects models. Results: Fifteen randomized controlled trials (RCTs) were included. There were no differences between clonidine and the control drug regarding the duration of analgesia (SMD = -0.71, 95%CI: -1.64, 0.23; I 2 = 95.5%, Pheterogeneity < 0.001), pain score (SMD = 0.35, 95%CI: -0.28, 0.98; I 2 = 80.8%, Pheterogeneity < 0.001), and requirement for additional analgesia (OR = 8.77, 95%CI: 0.70, 110.58, I 2 = 81.9%, Pheterogeneity = 0.004), but using clonidine resulted in fewer complications than the control drugs (OR = 0.33, 95%CI: 0.20, 0.54, I 2 = 21.8%, Pheterogeneity = 0.217). The sensitivity analysis showed that the results were robust. A publication bias was observed. Conclusion: Clonidine has the same efficacy as the other adjuvants for caudal epidural block for pediatric surgery but fewer complications. These results support clonidine as an adjuvant to local anesthetic, but additional studies should be conducted.

9.
Cell Death Dis ; 12(11): 972, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34671010

RESUMO

Obesity is an epidemic affecting 13% of the global population and increasing the risk of many chronic diseases. However, only several drugs are licensed for pharmacological intervention for the treatment of obesity. As a master regulator of metabolism, the therapeutic potential of AMPK is widely recognized and aggressively pursued for the treatment of metabolic diseases. We found that elaiophylin (Ela) rapidly activates AMPK in a panel of cancer-cell lines, as well as primary hepatocytes and adipocytes. Meanwhile, Ela inhibits the mTORC1 complex, turning on catabolism and turning off anabolism together with AMPK. In vitro and in vivo studies showed that Ela does not activate AMPK directly, instead, it increases cellular AMP/ATP and ADP/ATP ratios, leading to AMPK phosphorylation in a LKB1-dependent manner. AMPK activation induced by Ela caused changes in diverse metabolic genes, thereby promoting glucose consumption and fatty acid oxidation. Importantly, Ela activates AMPK in mouse liver and adipose tissue. As a consequence, it reduces body weight and blood glucose levels and improves glucose and insulin tolerance in both ob/ob and high-fat diet-induced obese mouse models. Our study has identified a novel AMPK activator as a candidate drug for the treatment of obesity and its associated chronic diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Produtos Biológicos/uso terapêutico , Glucose/metabolismo , Macrolídeos/uso terapêutico , Animais , Produtos Biológicos/farmacologia , Peso Corporal , Descoberta de Drogas , Humanos , Macrolídeos/farmacologia , Masculino , Camundongos , Camundongos Obesos
10.
J Mol Biol ; 433(22): 167269, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34571015

RESUMO

VERNALIZATION1 (VRN1) is a transcriptional repressor involved in plant vernalization that undergoes liquid-liquid phase separation (LLPS) with DNA. The naturally occurring VRN1-like proteins contain two B3 DNA binding domains connected by an intrinsically disordered region (IDR). The IDR length in VRN1-like proteins has a broad distribution, while the charge segregation pattern is largely conserved. We studied the effect of IDR length and charge segregation on DNA-induced VRN1 phase separation. When only neutral residues (Pro-Ser repeats) were used, the phase separation behavior is sensitive to IDR length, changing from gel-like aggregates (L = 40) to liquid-like droplets (L = 100-120) and clear solution (L = 160). When a pair of continuous patches of positive and negative residues were added to the IDRs, all the VRN1 variants formed robust and durable droplets with DNA independent of the IDR length. To test how robust the system is, we introduced folded green fluorescent protein or the enzyme GPX4 into VRN1 variants with charge segregation in IDR, the resulting proteins form LLPS with DNA as well. Our study implies that VRN1-like proteins use conserved charge segregation pattern to retain functional LLPS during evolution, and demonstrates the possibility of using this system to design novel biosensors or bio-factories by introducing various functional modules.


Assuntos
Proteínas de Arabidopsis/química , DNA de Plantas/metabolismo , Proteínas Intrinsicamente Desordenadas/química , Proteínas Repressoras/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , DNA de Plantas/química , Difusão Dinâmica da Luz , Polarização de Fluorescência , Recuperação de Fluorescência Após Fotodegradação , Transferência Ressonante de Energia de Fluorescência , Proteínas Intrinsicamente Desordenadas/metabolismo , Simulação de Dinâmica Molecular , Domínios Proteicos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/química
11.
Lancet Reg Health West Pac ; 12: 100166, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34527964

RESUMO

BACKGROUND: The discipline of anaesthesiology in China has undergone historical changes and development during the past century. However, nationwide comprehensive data on the current status of each hospital department providing anaesthesia care has been lacking since the discipline was first established in China. This information is essential for effective regulation of healthcare policies by both the professional associations and the government health ministry. Therefore, a nationwide survey was set up in 2018 to investigate the current status of Chinese anaesthesiology. This paper reports the findings of the survey. METHODS: We performed a cross-sectional nationwide census survey of the current status of each hospital department providing anaesthesia care in 31 provinces across the Chinese mainland. The content of the survey included general information of the department, the hospital level and scale, the volume of the anaesthesiology department, the characteristics of anaesthesiologists, and the caseload of the anaesthesiology departments. Face-to-face interviews were performed by trained interviewers. The Chinese Anaesthesiology Department Tracking Database (CADTD) was established during the survey. Data quality control was undertaken by the investigation committee throughout the survey process. FINDINGS: The nationwide census survey was completed by 11,432 hospital departments providing anaesthesia care throughout mainland China from June 1, 2018 to June 30, 2019. Among the 11,432 departments, 4591 (40•16%) belonged to specialised hospitals, while 6841 (59•84%) were affiliated to general hospitals. The proportion of independent anaesthesiology departments was 45•15% in mainland China. There was a total of 92,726 anaesthesiologists, or 6•7 per 100,000 of the population. Regions with better economic conditions had more anaesthesiologists per 100,000 of the population. From 2015 to 2017, the workload of anaesthesiologists has increased by 10%. INTERPRETATION: The discipline of anaesthesiology in China has entered a rapid development phase. However, the current status of anaesthesiology is not well defined, which makes it difficult to meet the needs of the increasing Chinese healthcare demand. The evidence from this survey offers valuable information for policy makers and anaesthesiology associations to monitor the development of the discipline and regulate healthcare policies effectively. FUNDING: National Key Research and Development Program of China (Grant No. 2018YFC2001900).

12.
J Nat Prod ; 84(8): 2336-2344, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34384027

RESUMO

Fluostatins belong to the atypical angucyclinone aromatic polyketides featuring a distinctive tetracyclic benzo[a]fluorene skeleton. To understand the formation of the heavily oxidized A-ring in fluostatins, a flavin adenine dinucleotide-binding oxidoreductase-encoding gene flsP was inactivated, leading to the production of an unprecedented 1,4-oxazepine-linked seco-fluostatin heterodimer difluostatin I (7) and five new fluostatin-related derivatives, fluostatins T-X (8-12). Their structures were elucidated by mass spectrometry, nuclear magnetic resonance, X-ray diffraction analysis, and biosynthetic considerations. Difluostatin I (7) represents the first example with an A-ring-cleaved 3',4'-seco-fluostatin skeleton. The absolute configuration of fluostatin T (8) was determined by X-ray diffraction analysis. Fluostatin W (11) contains an uncommon isoxazolinone ring. These findings highlight the structural diversity of fluostatins.


Assuntos
Micromonospora/enzimologia , Oxazepinas/química , Oxirredutases/genética , Policetídeos/química , Candida albicans , Linhagem Celular Tumoral , Dimerização , Inativação Gênica , Humanos , Micromonospora/genética , Estrutura Molecular
13.
Angew Chem Int Ed Engl ; 60(42): 22688-22692, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34414645

RESUMO

Although copper-nitrene has been extensively studied as a versatile active species in various transformations, asymmetric reactions involving copper-nitrene have been limited to the aziridination of olefins. Herein, we report the novel copper-nitrene-catalyzed desymmetric oxaziridination reaction of cyclic diketones with alkyl azides and the subsequent rearrangement of the resulting highly active intermediate, which produces a synthetically challenging chiral bicyclic lactam containing a quaternary carbon center. This procedure not only enriches the copper-nitrene-catalyzed asymmetric reactions, but also provides an alternative strategy to address the inherent challenges of catalytic asymmetric Schmidt reactions. This unique reaction could inspire the investigation of novel copper-nitrene-catalyzed asymmetric transformations and their reaction mechanisms.

14.
Org Biomol Chem ; 19(27): 6030-6037, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34190307

RESUMO

Coral-associated microorganisms are likely to play an important role in host defense by the production of antimicrobials. Six new chromanones, namely, phomalichenones H-M (5, 6, and 8-11), and ten known analogues (1-4, 7, and 12-16) were isolated from the coral-associated fungus Parengyodontium album sp. SCSIO 40430. Their structures were elucidated by comprehensive spectroscopic analyses. In addition, the structure of 8 was confirmed by X-ray crystallographic analysis. Resolution using a chiral column showed that each of the compounds 1-8 was an enantiomeric mixture with variable enantiomeric excess (ee) values. Their absolute configurations were determined by a comparison of the experimental and calculated ECD data and by a modified Mosher's method. A plausible biosynthetic scheme was proposed for the production of 1-16. Compounds 2, 3, 13, and 14 were found to be active against Mycobacterium tuberculosis H37Ra with MIC values of 16-64 µg mL-1.


Assuntos
Hypocreales
15.
Fitoterapia ; 152: 104937, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34000328

RESUMO

Five new phenylspirodrimanes, stachybomycins A - E (1-5), together with four known compounds (6-9), were isolated from the marine-derived fungus Stachybotrys sp. SCSIO 40434. Their structures were elucidated by comprehensive spectroscopic analyses of NMR and HRESIMS. The absolute configuration of 1 was confirmed by single crystal X-ray diffraction analysis. Compounds 5 and 7 showed moderate antibacterial activities against Micrococcus luteus, Staphylococcus aureus and methicillin resistant Staphylococcus aureus with minimal inhibition concentration (MIC) values of 8, 16 and 16 µg mL-1, respectively.


Assuntos
Antibacterianos/farmacologia , Produtos Biológicos/farmacologia , Stachybotrys/química , Antibacterianos/isolamento & purificação , Organismos Aquáticos/química , Produtos Biológicos/isolamento & purificação , China , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Micrococcus luteus/efeitos dos fármacos , Estrutura Molecular , Oceano Pacífico , Staphylococcus aureus/efeitos dos fármacos
16.
Front Oncol ; 11: 633579, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968733

RESUMO

BACKGROUND: MYCN is an oncogenic transcription factor of the MYC family and plays an important role in the formation of tissues and organs during development before birth. Due to the difficulty in drugging MYCN directly, revealing the molecules in MYCN regulatory networks will help to identify effective therapeutic targets. METHODS: We utilized network controllability theory, a recent developed powerful tool, to identify the potential drug target around MYCN based on Protein-Protein interaction network of MYCN. First, we constructed a Protein-Protein interaction network of MYCN based on public databases. Second, network control analysis was applied on network to identify driver genes and indispensable genes of the MYCN regulatory network. Finally, we developed a novel integrated approach to identify potential drug targets for regulating the function of the MYCN regulatory network. RESULTS: We constructed an MYCN regulatory network that has 79 genes and 129 interactions. Based on network controllability theory, we analyzed driver genes which capable to fully control the network. We found 10 indispensable genes whose alternation will significantly change the regulatory pathways of the MYCN network. We evaluated the stability and correlation analysis of these genes and found EGFR may be the potential drug target which closely associated with MYCN. CONCLUSION: Together, our findings indicate that EGFR plays an important role in the regulatory network and pathways of MYCN and therefore may represent an attractive therapeutic target for cancer treatment.

17.
Org Biomol Chem ; 19(19): 4243-4247, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-33885700

RESUMO

Benzofluorene-containing atypical angucyclines are an important family of natural products with a broad spectrum of antibacterial and cytotoxic properties. Interestingly, symmetric and asymmetric dimers showed better activity than the monomer in this class of compounds. Herein, we reported the isolation of a new asymmetric dimer nenestatin B (2) from the deep sea actinomycete Micromonospora echinospora SCSIO 04089 and a monomer nenestatin C (3) from an NmrA family regulatory protein coding gene nes18 inactivated mutant. The structural elucidation of 3 indicated the essential role of Nes18 in the biosynthetic pathway of 2, specifically in dimerization via C-C bond formation.


Assuntos
Dimerização
18.
Molecules ; 26(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670784

RESUMO

The fungus strain SCSIO 40433 was isolated from an Arctic-derived glacier sediment sample and characterized as Tolypocladium cylindrosporum. A new compound, cylindromicin (1), and seven known secondary metabolites (2-8) were isolated from this strain. The chemical structures of these compounds were elucidated by comprehensive spectroscopic analyses. Cylindromicin (1) featured a 3,4-dihydro-2H-pyran skeleton. The absolute configuration of compound 1 was assigned via interpretation of key Nuclear Overhauser Effect Spectroscopy (NOESY) correlations and Electronic Circular Dichroism (ECD) calculation. Cylindromicin (1) exhibited significant tyrosinase inhibition activity. This study highlights Polar fungi as a potential resource for new bioactive natural products.


Assuntos
Hypocreales/química , Piranos/isolamento & purificação , Regiões Árticas , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Piranos/química , Piranos/farmacologia , Pironas/química , Pironas/farmacologia , Relação Estrutura-Atividade
19.
Org Lett ; 23(8): 2858-2862, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33703905

RESUMO

Two polycyclic thioalkaloides dassonmycins A (1) and B (2) were isolated from Nocardiopsis dassonvillei SCSIO 40065 associated with marine sponge Petrosia sp. Structures of 1 and 2 were elucidated by comprehensive spectroscopic analysis and confirmed by single-crystal X-ray diffraction experiments, to have a 6/6/6/6-fused tetracyclic ring featuring a naphthoquinone[2,3-e]piperazine[1,2-c]thiomorpholine scaffold. Compound 2 formed a caged core through an additional ether bridge. Both compounds exhibited moderate antibacterial and cytotoxic activities.

20.
Nat Prod Res ; : 1-7, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33736548

RESUMO

Two new piericidins A5 (1) and G1 (2), a previously synthesized piericidin G2 (3), and two known piericidins A1 (4) and A2 (5) were isolated from the marine-derived Streptomyces sp. SCSIO 40063. The structures of 1-5 were elucidated by HRESIMS, 1 D, 2 D NMR data analyses and comparisons with the known compounds. Compound 2 showed moderate cytotoxicities against four human tumor cell lines SF-268, MCF-7, HepG2 and A549 with IC50 values between 10.0 and 12.7 µM.

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