Highly Emissive and Robust Cd-Based MOF with an Unprecedented Topology for Tetracycline Sensing.

Herein, an unprecedented cadmium-based metal-organic framework (JNU-106) fabricated by utilizing pyrazole-functionalized tetraphenylethylene ligands (Py-TPE) and rod-shaped secondary building units is reported, possessing a new (3,3,3,6,6,8)-connected topological network. Thanks to the ingeniously designed intramolecular charge transfer behavior, which originates from the congruent coplanarity between Py and TPE, JNU-106 exhibits intense green luminescence with a quantum yield increased by 1.5 times. The phenomenon of remarkable fluorescence quenching of JNU-106 reveals that it possesses extremely high anti-interference performance, superior sensitivity, and dedicated selectivity toward tetracycline antibiotics (TCAs) in aqueous solutions, which are comparable to those of the state-of-the-art porous sensing compounds. Taking the theoretical calculations and experimental results into account, the luminescence quenching is mainly attributed to the internal filtration effect and the static quenching effect. Considering the portable and rapid performance of JNU-106-based testing strips for sensing TCAs, the fabricated JNU-106 provides an alternative for ecological monitoring and environmental governance.

Marcytoglobosins A and B, Cytochalasans From a Marine Sponge Associated Chaetomium globosum 162105 Fungus.

Two new cytochalasans, marcytoglobosins A (1) and B (2) were isolated from the marine sponge associated fungus Chaetomium globosum 162105, along with six known compounds (3-8). The complete structures of two new compounds were determined based on 1D/2D NMR and HR-MS spectroscopic analyses coupled with ECD calculations. All eight isolates were evaluated for their antibacterial activity. Among them, compounds 3-8 displayed antibacterial effects against Staphylococcus epidermidis, Bacillus thuringiensis, Pseudomonas syringae pv. Actinidiae, Vibrio alginolyticus, and Edwardsiella piscicida with minimum inhibitory concentration (MIC) values ranging from 10 to 25 µg/mL.

A new 3,4-dinorsteroid from the marine sponge Cliona sp.

A new steroid, 2a-oxa-2-oxo-5ß-hydroxy-3,4-dinor-24-methylcholesta-22E-ene (1), together with 10 known ones (2-11), was isolated from the marine sponge Cliona sp. The structures of these compounds were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compound 1 was the third example of 3,4-dinorsteroid with a hemiketal at C-5 that was isolated from the natural source. In addition, the antibacterial activities of these compounds were also evaluated. However, none of them exhibited significant inhibition effects.

(+)- and (-)-Tedanine, a pair of new enantiomeric indolone alkaloids from the marine sponge Tedania sp.

(+)- and (-)-Tedanine [(+)-1 and (-)-1], a pair of new enantiomeric indolone alkaloids, along with nine compounds (2-10) were isolated from the marine sponge Tedania sp. The structures of (+)-1 and (-)-1 including absolute configurations were determined by spectroscopic analysis and quantum chemical calculation. Compounds (+)-1 and (-)-1 were the first examples of indolone alkaloids isolated from this genus. In addition, the cytotoxic and antibacterial activities of these compounds were also evaluated.

Two New Pairs of Enantiomeric Butenolides from the Marine Sponge Suberties sp.

Two new pairs of enantiomeric butenolides, (+)- and (-)-suberiteslide A, (+)- and (-)-subertieslide B had been obtained from the marine sponge Suberties sp. The structures with absolute configurations of these compounds were unequivocally determined by spectroscopic analyses and ECD (Electronic Circular Dichroism) method. It was the first separation of butenolides from the marine sponges of genus Suberites. Additionally, the anti-inflammatory, antibacterial and cytotoxic activities of these compounds were evaluated. The result indicated that only (-)-subertieslide B showed weak anti-inflammatory activity with the IC50 value of 40.8 µM.

A new chlorobenzoate derivative from the red alga Solieria sp.

A new chlorobenzoate derivative, solieriate (1), together with six known compounds (2-7), were isolated from the red alga Solieria sp. The structures of 1-7 were determined by comprehensive spectroscopic methods and X-ray diffraction analysis. Compound 1 is the first example of halogenated derivative isolated from this genus. In addition, 1 exhibited moderate antibacterial activity on A. baumannii with MIC value of 64 µg/ml.

Spongimides A and B, two new alkaloids from the marine sponge Spongia sp.

Two new alkaloids, spongimides A (1) and B (2), along with five known ones (3-7), were isolated from the marine sponge Spongia sp. The structures of 1 and 2 were determined by the spectroscopic methods (UV, IR, MS, and NMR) and X-ray diffraction analysis. Compounds 1, 3, and 4 were the first examples of 2,4-imidazolidinediones isolated from this genus. In addition, the cytotoxic and antibacterial activities of compounds 1 and 2 were also evaluated.

Two new halogenated metabolites from the red alga Laurencia sp.

Two new halogenated metabolites, laurenhalogens A (1) and B (2), along with four known ones (3-6), were isolated from the red alga Laurencia sp. The structures of 1 and 2 were determined by the means of UV, IR, MS, NMR and X-ray diffraction analysis. In addition, the antibacterial activities of 1-6 were also evaluated.

Mixed-Linker Isoreticular Zn(II) Metal-Organic Frameworks as Brønsted Acid-Base Bifunctional Catalysts for Knoevenagel Condensation Reactions.

Multicomponent metal-organic frameworks (MOFs) have received an increasing amount of attention due to their potential to produce new topologies, pore metrics, and functionalities compared to MOFs with a single metal cluster and one organic linker. Herein, five isoreticular Zn MOFs were obtained by mixing two types of linear ditopic linkers in a one-pot solvothermal synthesis. Interestingly, in the resulting Zn MOFs a six-connected cyclic trinuclear Zn(II) cluster and an eight-connected linear trinuclear Zn(II) cluster coexist, leading to an uncommon (6,8)-connected network. Catalytic activities toward the solvent-free Knoevenagel reactions were observed for all of these MOFs. Further experimental and computational studies suggest that they are Brønsted acid-base bifunctional catalysts. Through chemical modifications of dicarboxylate ligands, including their aromatic backbones and substituents, we have successfully implemented reticular chemistry for the modulations of pore sizes, surface areas, and catalytic performances in a series of four-component isoreticular MOFs.

Nurses' perceptions regarding barriers to implementing the Internet Plus Nursing Service programme: A qualitative study.

AIM: The aim of this work is to investigate nurses' perceptions of barriers constraining the implementation of the Internet Plus Nursing Service program. BACKGROUND: The Internet Plus Nursing Service programme helps meet the demands of an ageing population, people with chronic diseases, the disabled, and home convalescents, and affirms the value of nurses. However, this programme has failed to elicit nurses' active participation, and there is limited knowledge regarding nurses' perceptions of the barriers to the programme's implementation. METHODS: A qualitative study was conducted. Thematic analysis of the data was performed. RESULTS: The analysis yielded three main themes: a sense of insecurity, role conflict, and a lack of support. CONCLUSION: This study explores nurses' perspectives on the factors impeding the implementation of the programme, which are identified as being insufficient protection and support on nurses at personal, sociocultural, infrastructural, and organizationallevels. IMPLICATIONS FOR NURSING MANAGEMENT: The study results will guide the department of nursing management to foster supportive work and social environment for nurses, which will decrease their feeling of insecurity and role conflicts and provides them enough infrastructural and organizational supports through proposing emergency code system and improving training system and team collaboration.

Asperfloketals A and B, the First Two Ergostanes with Rearranged A and D Rings: From the Sponge-Associated Aspergillus flocculosus 16D-1.

Asperfloketals A (1) and B (2), two 1(10 → 6)-abeo-14,15-secosteroids featuring a novel trioxahexaheterocyclic ring system, were isolated from the sponge-associated fungus Aspergillus flocculosus 16D-1. Their structures were elucidated by extensive spectroscopic analysis and NMR chemical shifts calculations, supported by DP4+ probability analysis, and their absolute configurations were determined by ECD calculations and the modified Mosher's method. Asperfloketals A and B showed strong anti-inflammatory activity in the CuSO4-induced transgenic fluorescent zebrafish but displayed no cytotoxicity against HeLa, HepG2, and SW480 cell lines.

Three New Butenolides from the Green Alga Caulerpa racemosa var. turbinata.

Three new butenolides, caulerpalide A and a pair of enantiomers, (+)-caulerpalide B and (-)-caulerpalide B, together with seven known compounds, have been isolated from the green alga Caulerpa racemosa var. turbinata. All these structures were determined by spectroscopic techniques. The absolute configurations of caulerpalide A, (+)-caulerpalide B and (-)-caulerpalide B were elucidated by the method of ECD calculation. This is the first separation of butenolides from the algae of genus Caulerpa. Additionally, the antibacterial activities of the nine isolated compounds were also evaluated.

Sinulaspirolactam A, a novel aza-spirocyclic valerenane sesquiterpenoid from soft coral Sinularia sp.

A novel valerenane sesquiterpenoid sinulaspirolactam A (1), together with five known compounds, was isolated from the soft coral Sinularia sp. Their structures were determined by spectroscopic analyses. The absolute configuration of 1 was established by ECD calculation. Compound 1 was the first example of valerenane sesquiterpenoid bearing an aza-spiro[4.5] ring moiety, the plausible biogenetic pathway of which was proposed. Cytotoxic activities of these compounds were also evaluated.

Antineoplastic activity of linear leucine homodipeptides and their potential mechanisms of action.

Galaxamide is a rare cyclic homopentapeptide composed of three leucines and two N-methyl leucines isolated from marine algae Galaxaura filamentosa. The strong antitumor activity of this compound makes it a promising candidate for tumor therapy. The synthesis of galaxamide, however, is a complex process, and it has poor water solubility. On the basis of its special chemical composition, we designed a series of linear leucine homopeptides. Among seven dipeptide derivatives, five compounds with terminal protection groups and methyl substitution of the hydrogen in the amido group showed remarkable inhibitory effects against various cancer cells. N-tertbutyl-D-leucine-N-methyl-D-leucinebenzyl (A7), the only stereomer condensed by two D-leucines, showed the highest antineoplastic activity. A7-treated cells showed cell cycle arrest and morphological changes typical of cells undergoing apoptosis. The population of Annexin-V positive/propidium iodide-negative cells also increased, indicating the induction of early apoptosis. A7 promoted the cleavage of caspase-9 and caspase-3, as well as increased intracellular Ca levels and decreased the mitochondrial membrane potential. Collectively, certain linear leucine dipeptides derived from cyclic pentapeptide are able to inhibit tumor cell proliferation through cell cycle arrest and apoptosis induction. The N-methyl group in the side chain and the D/L conformation of the amino-acid residue are critical for their activity.

Unusual anti-inflammatory meroterpenoids from the marine sponge Dactylospongia sp.

Five new sesquiterpene hydroquinones, dactylospongins A-D (1-4) and 19-O-methylpelorol (10), as well as four new sesquiterpene quinones, melemeleones C-E (6-8) and dysidaminone N (9), were isolated from the marine sponge Dactylospongia sp. collected from the South China Sea, along with five known analogues, ent-melemeleone B (5), pelorol (11), 17-O-acetylavarol (12), 20-O-acetylavarol (13), and 20-O-acetylneoavarol (14). The structures were elucidated by spectroscopic data analyses and comparison with the published NMR data, while the absolute configurations of new structures were assigned by comparison between the experimental and calculated ECD spectra. Dactylospongins A (1) and B (2) are the first sesquiterpenoids with a benzothiazole ring from the marine environment. Anti-inflammatory evaluation showed that 1, 2, 4, 5, 9, and 10 showed potent inhibitory effects on the production of inflammatory cytokines (IL-6, IL-1ß, IL-8, and PEG2) in LPS-induced THP-1 cells with IC50 values of 5.1-9.2 µM; however, none of them showed significant effects on the production of MCP-1 and TNF-α. Additionally, 19-O-methylpelorol (10) exhibited cytotoxicity against lung cancer PC-9 cell lines with an IC50 value of 9.2 µM.

Popolohuanones G - I, Dimeric Sesquiterpene Quinones with IL-6 Inhibitory Activity from the Marine Sponge Dactylospongia elegans.

Chemical investigation of the marine sponge Dactylospongia elegans, collected from the South China Sea, afforded three new dimeric sesquiterpene quinones, popolohuanones G - I (1 - 3), together with two known analogs, popolohuanones B (4) and C (5). The new structures were determined by HR-ESI-MS and 1D- and 2D-NMR analyses. All the five compounds showed no cytotoxic activity against five human cancer cell lines, while popolohuanone H (2) showed potent inhibitory activity against IL-6, an inflammatory cytokine, at the concentration of 10 µm.

Two pairs of unusual melibiose and raffinose esters from Scrophularia ningpoensis.

A pair of unusual melibiose esters (1α/1ß) and a pair of unusual raffinose esters (2α/2ß), were isolated from Scrophularia ningpoensis. Structures of them were established by detailed spectroscopic analyses to be 6-O-(E)-cinnamoyl-α-d-galactopyranosyl-(1→6)-α(ß)-d-glucopyranose (1α/1ß) and 6-O-(E)/(Z)-cinnamoyl-α-d-galactopyranosyl-(1→6)-α-d-glucopyranosyl-(1→2)-ß-d-fructofuranose (2α/2ß), respectively. All these compounds were evaluated for antifouling activity against the settlement of Balanus amphitrite larvae, along with the cytotoxic effect against the proliferation of HeLa cell lines.

Chaetochromones A - C, Three New Polyketides from Mangrove Plant Derived Endophytic Fungus Phomopsis sp. SCSIO 41006.

Three new polyketides, chaetochromones A - C (1 - 3), together with a chromone (4), were isolated from the ethyl acetate extract of mangrove-derived fungus Phomopsis sp. SCSIO 41006. Their structures were elucidated by means of spectroscopic techniques (UV, IR, MS, 1D- and 2D-NMR). The absolute configurations of the new compounds were established by CD data.

Aspergchromones A and B, two new polyketides from the marine sponge-associated fungus Aspergillus sp. SCSIO XWS03F03.

Two new polyketides, aspergchromones A (1) and B (2), together with five known compounds, secalonic acid D (3), noreugenin (4), (3S)-5-hydroxymellein (5), (4S)-6-hydroxyisosclerone (6), and (-)-regiolone (7), were isolated from the ethyl acetate extract of marine sponge-derived fungus Aspergillus sp. SCSIO XWS03F03. Their structures were elucidated by means of spectroscopic techniques (1D and 2D NMR, MS, UV, and IR). The absolute configurations of the new compounds were established by ECD calculations. Compound 3 showed moderate antimicrobial activity.

A new α-pyrone from the deep-sea actinomycete Nocardiopsis dassonvillei subsp. dassonvillei DSM 43111(T).

A new α-pyrone, nocapyrone S (1), together with five known compounds (2-6), were isolated from the deep-sea actinomycete Nocardiopsis dassonvillei subsp. dassonvillei DSM 43111(T). Their structures were determined by spectroscopic analyses. The absolute configuration of 1 was established by quantum approaches. Cytotoxic activity of 1 was evaluated against K562, MCF-7, SGC7901, A375, Hela, and HepG2 cell lines.