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A new naphthalene derivative, 7-acetyl-8-hydroxy-3-methoxy-6-methylnaphthalen-1-yl acetate (1), has been isolated from the stem of Rhamnus crenata, together with eight known compounds 2–9. The structure of new compound 1 was determined through spectroscopic and MS analyses. Among the isolates, emodin (3), physcion (4), quercetin 3-O-α-L-rhamnopyranoside (5), and quercetin 7-O-α-L-rhamnopyranoside (6) showed potent inhibition with IC50 values of 33.18 ± 2.73, 35.52 ± 3.27, 28.05 ± 1.85, and 26.41 ± 3.01 μM, respectively, against LPS-induced NO generation. In addition, compounds 3, 5, and 6 also showed potent DPPH radical scavenging activities with IC50 values of 95.47 ± 6.18, 68.27 ± 5.38, and 66.25 ± 4.20 μM, respectively. [ABSTRACT FROM AUTHOR]

In the title molecule, C27H27NO, the naphthalene and quinoline groups are both planar and subtend a dihedral angle of 15.47 (7)°. They are nearly coplanar with the cis-vinyl bridge and the hexyloxy chain, which adopts an all-trans conformation, resulting in transannular bifurcated intramolecular C—H...N,O contact. The crystal structure features γ-packing of the aromatic moieties, while the parallel packing of alkyl chains resembles that of alkanes.

• WH could continuously recognize of Cu2+ and EDTA in HEPES system. • The detection limits of WH for Cu2+ and EDTA were as low as 29.66 and 172.13 nmol· L −1, respectively. • WH had excellent AIE performance. • WH could be used for the detection of Cu2+ in alcoholic beverages. A novel fluorescent probe, WH , was successfully designed and synthesized. WH demonstrated continuous detection capabilities for Cu2+ and EDTA in the HEPES system. Specifically, the introduction of copper ions resulted in fluorescence quenching, while the addition of EDTA led to the recovery of fluorescence. The detection limits of WH for Cu2+ and EDTA were calculated to be 29.66 and 172.13 nmol· L −1, respectively. Moreover, WH exhibited AIE property in THF/H 2 O system. According to the Job's plot, 1H NMR titration and mass spectrometry, WH could form a complex with Cu2+ in a 1:1 ratio, and the combinding constant was 8.2 × 103 L mol−1. WH exhibited outstanding selectivity, high sensitivity, large Stokes shift and strong anti-interference ability. Furthermore, WH had been successfully applied in the detection of Cu2+ in beer and red wine, showcasing its promising potential for practical application. [Display omitted] [ABSTRACT FROM AUTHOR]

We are reporting a naphthalene-hydrazone-coupled, π···hole-assisted selective colorimetric cyanide receptor L, (E)-2-((naphthalen-1-yl)methylene)-1-(perfluorophenyl)hydrazine. This colorimetric receptor L shows high selectivity toward cyanide anion through ICT mechanism. The binding strength and sensitivity of the chemo-sensor L toward cyanide is found to be 2.813 × 104 and 6 × 10–6 M, respectively. This preferential cyanide binding is mainly attributed due to the presence of pentafluoro-substituted electron-deficient phenyl moiety which is subsequently supported with UV–Vis and 1H-NMR spectroscopic studies. The detailed naked-eye colorimetric experiment, UV–Vis spectrometric titration, 1H-NMR analysis, IR spectroscopic investigation and molecular electrostatic potential (MEP) studies support the proposed binding mechanism. The reference receptor L1 does not show any response with tested anions including cyanide and fluoride. The receptor L acts as "Molecular Swan." Swans are birds of the family Anatidae; the swan if offered a mixture of milk and water is said to be able to drink the milk alone. Similar way, if we offer mixture of various anions, the receptor L is able to take only cyanide anion. [ABSTRACT FROM AUTHOR]

OSMAC approach was performed on the soft coral-derived fungus Trichoderma harzianum (XS-20090075) leading to the significant changes of its secondary metabolites by using two different cultures. A new naphthalene derivative, trichoharzin B (1) and a new natural product, methyl-trichoharzin (2) were isolated by using rice medium. Whereas, a new natural product, ethyl 2-bromo-4-chloroquinoline-3-carboxylate (9) was obtained by using Czapek's medium. Their structures were established by extensive spectroscopic investigation. The absolute configuration of 5 was determined by single-crystal X-ray diffraction. Compound 9 was the first halogenate quinoline derivative isolated from the genus of Trichoderma. [ABSTRACT FROM AUTHOR]

The title naphthalene derivative, C24H20O2, features 4-methyoxy-substituted benzene rings in the 1 and 4 positions of the naphthalene ring system. There are two crystallographically independent molecules (A and B) in asymmetric unit. The independent molecules have very similar conformations in which the naphthalene ring systems are only slightly bent, exhibiting dihedral angles between the constituent benzene rings of 3.76 (15) and 3.39 (15)° for A and B, respectively. The pendent 4-methyoxybenzene rings are splayed out of the plane through the naphthalene ring system to which they are connected [range of dihedral angles = 59.63 (13) to 67.09 (13)°]. In the crystal, the molecular packing is consolidated by intermolecular C—H...π interactions, leading to supramolecular chains along the b axis. The chains assemble without directional interactions between them.

Abstract A designed naphthalene derivative (potassium 2,2′-(naphthalen-1-ylazanediyl)diacetate, ND) was synthesized successfully which characterized by spectroscopic techniques (NMR, IR and HRMS-ESI-TOF). The sensitivity and selectivity were high toward Ba2+ in aqueous solution (100.0 mM HEPES buffer, 100.0 mM KNO 3 , pH 7.4) over a wide variation of metal ions such as Li+, Na+, K+, Cs+, Mg2+, Ca2+, Al3+, Pb2+, Fe2+, Fe3+, Co2+, Ni2+, Cu+, Cu2+, Ag+, Zn2+, Cd2+ and Ce3+. The limit of detection (LOD) was found to be 9.56×10−8 M. Density functional theory (DFT) calculations at the B3LYP level employing the 6-31G(d,p) and LANL2DZ basis set were performed for optimization of ND and ND -Ba2+ complex. The calculated results were consistent with a favorable complexation corresponding to the proposed coordination. Graphical Abstract Unlabelled Image Highlights • ND can detect barium(II) with limit of detection in nanomolar of concentration. • The ND probe is selective to barium(II) as pH of living cell. • It is a fluorescence turn-on for detection of barium(II) in human body. • The binding of complex from experiment can confirm by DFT. [ABSTRACT FROM AUTHOR]

Two new compounds (1 and 2), together with six known compounds (3-8), were obtained from the Cladosporium sp. JJM22, an endophytic fungus isolated from the stem bark of the mangrove plant Ceriops tagal collected in South China Sea. Their structures were elucidated on the basis of detailed spectroscopic analysis. The absolute configurations of 1 and 2 were confirmed by the comparison of optical rotation and the CD data with those of known compounds. The inhibitory activities of the isolated compounds against six terrestrial pathogenic bacteria and human cervical carcinoma Hela cell line were evaluated. Compound 3 exhibited a broad spectrum of antibacterial activities. [ABSTRACT FROM AUTHOR]

Organic molecules having extended π-conjugated moieties is useful for creating ‘dynamic’ functional materials by modulating the photophysical properties and molecular packing through non-covalent interactions. Herein, we report the photoluminescence properties of a luminogen, NBA, exhibiting aggregation-induced emission (AIE) characteristics, synthesized by Knoevenagel condensation reaction between 2-Hydroxy naphthaldehyde and malononitrile. NBA emits strongly upon aggregation and in solid state with large Stokes shift whereas it is non emissive in pure solvents. The aggregation induced emission behavior of the compound was carried out in DMSO (good solvent)-water mixture (poor solvent) with water fraction ( f w) ranging from 0% to 98%. The AIE property of the luminogen were further exploited for fabricating rewritable fluorescent paper substrates that found applications in security printing and data storage where the written images or letters stored on the filter paper are invisible under normal light. [ABSTRACT FROM AUTHOR]

Cassia grandis is used for the treatment of skin disorders, back pain, aches, etc. in Vietnamese traditional medicine. In this paper, phytochemicals of the leaves were investigated. A new naphthalene derivative (1, cassgranon D) and, seven known compounds rutin (2), afzelin (3), quercitrin (4), epicatechin (5), (-)-epiafzelechin (6), isoquercitrin (7) and aloe emodin (8) were isolated from the ethyl acetate and methanol extracts. Their structures were elucidated by spectral evidences (UV, IR, MS, 1H, 13C, DEPT, HSQC and HMBC NMR), as well as by comparing with published data. [ABSTRACT FROM AUTHOR]

Different types of starting materials have been designed and their ability to undergo cascade reactions has been investigated. New polycycles containing five-, six-, and seven-membered rings are described via original cascade reactions. The process works via a twofold cyclocarbopalladation followed by C(sp 2 )-H or C(sp 3 )-H activation. During these cascades, the palladium is moving several times along the carbon structure forming three new C C bonds and three new cycles. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C11H9NO3, contains two molecules, A and B. In molecule A, the dihedral angle between the planes of the naphthalene ring system (r.m.s. deviation = 0.003 Å) and the nitro group is 89.9 (2)°, and the C atom of the methoxy group deviates from the naphthyl plane by 0.022 (2) Å. Equivalent data for molecule B are 0.008 Å, 65.9 (2)° and −0.198 (2) Å, respectively. In the crystal, molecules are linked by weak C—H...O interactions, forming [100] chains of alternating A and B molecules. Weak aromatic π–π stacking contacts, with a range of centroid–centroid distances from 3.5863 (9) to 3.8048 (9) Å, are also observed.

Five new compounds, named ancistronaphtosides A and B ( 1 and 2 ), anciscochine ( 3 ), anciscochine 6- O -β- d -glucopyranoside ( 4 ), and 4′-methoxy-5- epi -ancistecrorine A 1 ( 5 ), together with tortoside A ( 6 ) and 4-hydroxy-2-methoxyphenyl-6- O -syringoyl-β- d -glucopyranoside ( 7 ) were isolated from the methanolic extract of Ancistrocladus cochinchinensis . Their chemical structures were established using HR-ESI-MS, NMR spectroscopic, and chiroptical methods. Compound 5 significantly exhibited anti-proliferation against HL-60, LU-1, and SK-MEL-2 cells with IC 50 values of 5.0 ± 1.2, 6.5 ± 1.6, and 6.8 ± 2.0 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

A naphthalene-based two-photon fluorescent probe for thiophenols has been reported in this work. The probe can be applied to the quantification of thiophenols with a linear range covering from 2.0 × 10 −8 to 7.0 × 10 −6 mol L −1 . It exhibited a high selectivity and excellent sensitivity with a detection limit of 9.6 nM. Moreover, it was successfully used for practical detection of thiophenol in water samples with a good recovery, and two-photon imaging of thiophenol in live cells and tissues at a depth of 40–155 μm. [ABSTRACT FROM AUTHOR]

In the title compound, C20H17NO, the dihedral angle between the mean planes of the 4-methoxyphenyl ring and the naphthalene ring is 69.50 (7)°. The methoxy group is almost coplanar with the benzene ring to which it is connected [Cb—Cb—Om—Cm torsion angle of −7.9 (2)°; b = benzene and m = methoxy] and the imine group displays a C—C—N=C torsion angle is −57.2 (2)°. The imine (C=N) group has an E conformation. In the crystal, weak π–π interactions between the benzene rings [centroid–centroid distance = 3.7781 (10) Å] are observed.

An efficient fluorescent sensor based on β-hydroxy-α-naphthaldehyde [2-(quinolin-8′-yloxy) acetyl] hydrazone (HL) for Mg 2+ has been designed and synthesized. The receptor showed “off–on” fluorescent responses toward Mg 2+ in acetonitrile. The reasons for this phenomenon is that the addition of Mg 2+ to the solution of HL induce the formation of a 1:1 ligand–metal complex which inhibit excited-state intramolecular proton transfer (ESIPT). [ABSTRACT FROM AUTHOR]

A naphthalene derivative 2-hydroxy-α-naphthaldehyde-(2′-methylquinoline-4′-formyl) hydrazone (HL) as a fluorescent chemosensor for Al 3+ /Zn 2+ in ethanol and water (9:1, v/v) has been designed and synthesized. The receptor shows a large fluorescence enhancement at 509 nm and 543 nm in the present of Al 3+ and Zn 2+ , respectively. The excited-state intramolecular proton transfer (ESIPT) process, coupled with photoinduced electron transfer (PET) process are proposed to explain the observed spectral response. [ABSTRACT FROM AUTHOR]

Rhenium-catalyzed synthesis of naphthalene-substituted aryl bromides or iodides via C-H bond activation, and its use for palladium-catalyzed cross-coupling reactions with tetraethynylporphyrin are described. A series of novel meso-substituted tetraalkynylporphyrins with naphthalene moieties were obtained. [ABSTRACT FROM AUTHOR]

A new naphthalene derivative, 1-methyl-2,3-methylenedioxy-6-naphthalenecarboxylic acid methyl ester (1), and a new alkaloid, ( ± )-1-phenyl-2-imido-1-propanol (2), together with the four known compounds, ephedrine, pseudoephedrine, N-methylephedrine, and 6-methoxykynurenic acid, have been isolated from the stems of Ephedra sinica, a famous traditional Chinese herbal medicine. The structures of 1 and 2 were determined by spectroscopic methods, including 1D- and 2D-NMR experiments as well as HR-EI-MS analysis. [ABSTRACT FROM AUTHOR]

Abstract: Endoperoxides of naphthalene derivatives generate singlet oxygen under physiological conditions. Here we have synthesized a new endoperoxide of a naphthalene derivative, 1-buthylnaphthalene-4-propionate endoperoxide (BNPE), and studied its cytotoxic properties on HepG2 and HaCaT cells. BNPE induced cell death at much lower concentration than 1-methylnaphthalene-4-propionate endoperoxide (MNPE) and naphthalene dipropionate endoperoxide (NDPE). A positive correlation exists between the amount of endoperoxide incorporated into cells and its cytotoxic ability. The cytotoxic effect of BNPE was attenuated by α-tocopherol but not by sodium azide. In contrast, the effects of MNPE and NDPE were attenuated by both α-tocopherol and sodium azide. The caspase cascade in cells treated with endoperoxide was impaired. Caspase activity in a soluble protein fraction were inhibited similarly by the above three endoperoxides. These results suggest an abortive apoptotic pathway due to the suppression of caspase activation is a general feature of cell death induced by singlet oxygen. [Copyright &y& Elsevier]

We have designed and synthesized novel luminescent lanthanide complexes based on a naphthalene derivative. The coordination number of complexed ligands with Eu3+ ions is an important parameter to enhance the photoluminescence (PL) intensity. The photoluminescence spectra of Eu(III)-cored complexes exhibit a sharp red emission band at 612 nm, corresponding to the 5D0→7F2 transition of the trivalent Eu ion. The saturated europium complexes (C-2 and C-3) have much stronger PL intensity than the unsaturated 6-coordinated europium complex (C-1), due to the instability of the C-1 complex. In this paper, the synthesis and photophysical properties of novel europium(III)-chelated complexes based on a naphthalene derivative will be discussed. [ABSTRACT FROM AUTHOR]

In the title mol-ecule, C 27 H 27 NO, the naphthalene and quinoline groups are both planar and subtend a dihedral angle of 15.47 (7)°. They are nearly coplanar with the cis -vinyl bridge and the hex-yloxy chain, which adopts an all- trans conformation, resulting in transannular bifurcated intra-molecular C-H⋯N,O contact. The crystal structure features γ-packing of the aromatic moieties, while the parallel packing of alkyl chains resembles that of alkanes., (© Liu et al. 2022.)