Lipid droplet-specific near-infrared fluorescent probe for discriminating cancer and normal cells and diagnosing fatty liver.

Lipid droplets (LDs) is a newly essential organelle, which participates in carious physiological and pathological processes. LDs are considered as potential markers for disease diagnosis. Specific imaging of LDs is useful to understand their basic biological function and to diagnose diseases.

A simple ratiometric fluorescent probe for two-photon imaging of carbon monoxide in living cells and zebrafish.

Carbon monoxide (CO) is an important gas signaling molecule and has been widely involved in regulating important life processes. Effective monitoring of CO in living systems is critical. Combined with the accuracy of ratio detection and the advantages of two-photon imaging, a simple ratiometric two-photon fluorescent probe RTFP was rationally designed and synthesized using 7-(diethylamino)-4-hydroxycoumarin as a two-photon fluorophore and allyl carbonate as the reactive unit.

BODIPY-NBD dyad for highly selective and sensitive detection of hydrogen sulfide in cells and zebrafish.

Hydrogen sulfide (HS) has been regarded as the third endogenous gas signaling molecule. The development of suitable tools for HS detection in vitro and in vivo has always been a focus of research. In this work, three BODIPY-NBD dyads (o/m/p-BNP) were designed and synthesized using BODIPY and NBD as the fluorophore and quencher, respectively.

Selective Imaging of HClO in the Liver Tissue In Vivo Using a Near-infrared Hepatocyte-specific Fluorescent Probe.

Liver injury is typified by an inflammatory response. Hypochlorous acid (HClO), an important endogenous reactive oxygen species, is regarded as a biomarker associated with liver injury. Near-infrared (NIR) fluorescent probes with the advantage of deep tissue penetrating and low auto-fluorescence interference are more suitable for bioimaging in vivo.

A hepatocyte-targeting fluorescent probe for imaging isoniazid-induced hydrazine in HepG2 cells and zebrafish.

A hepatocyte-targeting fluorescent NH probe, GHP, was first designed and synthesized employing N-acetylgalactosamine (GalNAc) as the hepatocyte-targeting group and 3-nitrophthalimide as the recognition moiety. The probe can be used to selectively image NH produced by the hydrolysis of isoniazid in HepG2 cells and the liver of zebrafish in situ.

An isophorone-fused near-infrared fluorescent probe with a large Stokes shift for imaging endogenous nitroxyl in living cells and zebrafish.

Nitroxyl (HNO) plays an important role in multiple physiological and pathological processes, but the detailed generation mechanism of the endogenous HNO still remained to explore and perfect further. There is an urgent need to develop an excellent fluorescent probe for selective recognition and sensitive detection of HNO in biological systems. Near-infrared (NIR) fluorescent probes with a large Stokes shift are an ideal tool for bioimaging applications.

A seminaphthorhodafluor-based near-infrared fluorescent probe for hydrazine and its bioimaging in living systems.

Hydrazine (NH) has been classified as a potential carcinogen with its high toxicity, which can be readily absorbed through the skin or via breathing directly. Although some fluorescent probes have been developed for imaging of NH, very little can be used for imaging of NH in vivo because of its short emission wavelength. In this study, a new colorimetric and near-infrared (NIR) fluorescent probe CF-1 based on a seminaphthorhodafluor dye was successfully designed and used for hydrazine determination.

Synthesis of novel sugar or azasugar modified anthra[1,2-d] imidazole-6,11-dione derivatives and biological evaluation.

A series of novel, sugar or azasugar modified anthra[1,2-d] imidazole-6,11-dione derivatives, with different side chain were synthesized, using the synthetic route of imidazole cyclization reaction of 1,2-diaminoanthraquinone with various sugar (azasugar)-derived aldehydes, and imidazole cyclization reaction of 1,2-diaminoanthraquinone with chloroacetic acid and then followed by the nucleophilic substitution of N-alkylamino azasugar. Their biological activities against HIV-RT and cytotoxic activities against A549, Hela and MCF-7 cells were preliminary evaluated, most compounds showed similar HIV-RT inhibition to the control drug (AZT).

A convenient synthesis of novel aza-C-disaccharide analogues.

Novel aza-C-disaccharide analogues have been conveniently synthesized by using the isoxazoline-linked C-disaccharide derivatives as the intermediates. Firstly, the C=N of isoxazoline was reduced to C-N by using DIBAL-H as reducing agent, then followed by the tandem multi-step reactions through catalytic hydrogenation with Pd(OH)2/C involving debenzylated, reductive cleavage of the N-O, condensation-cyclization of the aldehyde and the in situ generated amine group to form imine C=N and then C=N hydrogenation to form C-N, thus providing a practical and new access to the synthesis of novel aza-C-disaccharide analogues.

Synthesis of bi-/tricyclic azasugars fused thiazinan-4-one and their HIV-RT inhibitory activity.

Novel bi-/tricyclic azasugars fused thiazinan-4-one were conveniently synthesized by the tandem Staudinger/aza-Wittig/cyclization reaction under microwave radiation. The aryl group (phenyl or pyridyl) in mercaptan acid had an important effect on the formation of the diastereomers of the tricyclic hybrids 12b-15b. The new bi/tricyclic azasugars 3a-8a, 4b, 6b, 8b and the known ones 2a, 2b were examined for their HIV reverse transcriptase (RT) inhibitory activities.

A convenient synthesis of N-linked diglycose derivatives based on one-pot tandem Staudinger/aza-Wittig/reduction and biological evaluation.

A series of novel N-linked diglycose derivatives 9 and 10 were conveniently and directly synthesized based on the key step of one-pot tandem Staudinger/aza-Wittig/reduction reaction from the azido sugar and sugar-derived aldehyde followed by deprotection. The biological activities against glycosidases (α-amylase, α-glucosidase, and β-glucosidase) and HIV-RT and antitumor activity of these compounds were preliminarily evaluated.

Synthesis and biological activities of novel isoxazoline-linked pseudodisaccharide derivatives.

A series of novel isoxazoline linked pseudodisaccharide derivatives were regiospecifically synthesized by 1,3-dipolar cycloaddition of α-allyl-C-glycopyranosides and sugar-derived nitrile oxides with good yields. The structures of the compounds were characterized by NMR spectroscopy and MS spectrometry and confirmed by the X-ray crystallographic analysis of compound ((5S)-3-(2,3-O-isopropylidene-5-deoxy-d-lyxofuranose-4-yl)isoxazoline-5-yl) methyl α- C-D-galactopyranoside. Their biological activities against glycosidases (α-amylase, α-glucosidase, and β-glucosidase) and HIV-RT, and antitumor activity were preliminarily evaluated.

DNA binding and anticancer activity of naphthalimides with 4-hydroxyl-alkylamine side chains at different lengths.

A series of novel naphthalimide derivatives modified with various hydroxyl-alkylamines at 4-position have been synthesized. Their DNA binding properties were investigated by UV-Vis, fluoescence, and circular dichroism (CD) spectroscopies and thermal denaturation. The results showed that compounds 3a-e as the DNA intercalator exhibited middle binding affinities with Ct-DNA.

Synthesis of C-Pseudonucleosides Bearing Thiazolidin-4-one as a Novel Potential Immunostimulating Agent.

Several novel C-pseudonucleosides bearing thiazolidin-4-one were synthesized by one-pot three-component condensation using unprotected sugar aldehyde at room temperature, and their effects on T cells, B cells, the cytokine secretion of IL-2, IL-4, and IFN-γ, T cell-associated molecules (CD3, CD4, CD8), and B cell-associated molecules (CD19) were first evaluated. The experimental data demonstrated that such thiazolidin-4-one C-pseudonucleosides hold potential as immunostimulating agents.

Synthesis and antitumor activity of novel ribonucleosides with C-5 OH replaced by a diaminopyrimidinyl group.

A series of novel ribonucleosides with C-5 OH replaced by a diaminopyrimidinyl group were synthesized by successively nucleophilic substitutions of 5'-deoxy-5'-amino-ribonucleosides with 2,4-dichloropyrimidine and then with various fatty amines under microwave irradiation. Their anticancer activities in vitro were preliminarily evaluated. Compounds 7a and 8a only exhibited anticancer activity against A549 cell line with the IC(50) values of 10.

Synthesis and biological activity of novel 5'-arylamino-nucleosides by microwave-assisted one-pot tandem Staudinger/aza-Wittig/reduction.

Novel pseudonucleosides with benzylamino group on 5'-position (4) were synthesized by using the microwave-assisted one-pot tandem Staudinger/aza-Wittig/reduction reaction in good yields of 55.2-71.7%.

Synthesis of alkylated aminofluorenes by palladium-catalyzed substitution at halofluorenes.

New N-substituted 2-amino-9,9-dialkylfluorenes optionally bearing electron-withdrawing substituents such as nitro or cyano in position 7 can be synthesized starting from 2-halo-9,9-dialkylfluorenes by Pd-catalyzed substitution with amines. Chiral amino groups can be introduced by this method too. 2-N,N-Dimethylamino-7-nitro-9H-fluorene was obtained in a convenient way by reductive amination.