Synthesis And Reactions Of 2-Hydroxy-4-Oxo-4-(2,3,5,6-Tetrafluoro-4- Methoxyphenyl)-But-2-Enoic Acid Methyl Ester

2-Hydroxy-4-oxo-4-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-but-2-enoic acid methyl ester (1) was synthesized by the reaction of pentafluoroacetophenone with dimethyl oxalate in the presence of sodium methylate. Subsequently, reactions of compound 1 with aniline, o-phenylenediamine, and o-aminophenol were investigated. In addition, the thermal cyclization of ester 1 was studied and led to the formation of 5,6,8-trifluoro-7-methoxy-4-oxo-4H-chromene-2-carboxylic acid methyl ester (6) due to nucleophilic substitution of the 3-fluoro group. Hydrolysis of compound 1 and subsequent cyclization by treatment with SOCl2 gave 5-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-furan-2, 3-dione (3). Thermal decarbonylation of compound 3 under mild conditions resulted in the formation of 3-(2,3,5,6-tetrafluoro-4-methoxyphenyl)- propene-1,3-dione (4) which dimerized to pyranone 5. © 2003 Elsevier Science B.V. All rights reserved

Portable bioluminescence systems and methods for in vivo monitoring of molecular and metabolic events in animals

A system for monitoring biological processes in vivo is provided. The system comprises an implantable luciferase biosensor comprising luciferase in a biocompatible matrix and a caged luciferin probe. The caged luciferin probe can be administered to a living subject and upon encountering a biological activity, e.g., enzyme activity, the caged luciferin probe releases free luciferin which can then interact with the biosensor luciferase to generate light. The light can then be detected and/or measured by a light detector. Compositions, methods and kits related to the system are provided herein

Bioorthogonal chemistry in bioluminescence imaging

Bioorthogonal chemistry has developed significant over the past few decades, to the particular benefit of molecular imaging. Bioluminescence imaging (BLI) along with other imaging modalities have significantly benefitted from this chemistry. Here, we review bioorthogonal reactions that have been used to signific antly broaden the application range of BLI

Anticancer And Antithrombin Activity Of Russian Plants

A chromogenic bioassay was utilized to determine the antithrombin activity of the methylene chloride and methanol extracts prepared from forty-five plants of Russia. Mouse leukemia cells (L1210) were utilized to screen these extracts for activity against cancer. The results indicated that eight plant extracts demonstrated 90% or higher activity in the inhibition of thrombin. Also, nine methanol extracts demonstrated activity of 90% or higher in the inhibition of mouse leukemia L1210 cells. The methanol extracts of Quercus robur and Sanguisorba officinalis demontrated high activity against both thrombin and cancer. © 2002 Elsevier Science Ireland Ltd. All rights reserved

Azacyanine dyes and use thereof

The application provides fluorescent dyes, which are cyanine dyes that incorporate additional aza moieties in the indolenium heterocycles and/or in the methine chains connecting them. Symmetrical and unsymmetrical chemically reactive azacyanine dyes are described for conjugation, as well as their bioconjugates for in-vitro and in-vivo assays and fluorescence imaging

In Vivo Molecular Bioluminescence Imaging: New Tools and Applications

in vivo bioluminescence imaging (BLi) is an optical molecular imaging technique used to visualize molecular and cellular processes in health and diseases and to follow the fate of cells with high sensitivity using luciferase-based gene reporters. The high sensitivity of this technique arises from efficient photon production, followed by the reaction between luciferase enzymes and luciferin substrates. Novel discoveries and developments of luciferase reporters, substrates, and gene-editing techniques, and emerging fields of applications, promise a new era of deeper and more sensitive molecular imaging

Real-Time Imaging and Quantification of Peptide Uptake in Vitro and in Vivo

Peptides constitute an important class of drugs for the treatment of multiple metabolic, ontological, and neurodegenerative diseases, and several hundred novel therapeutic peptides are currently in the preclinical and clinical stages of development. However, many leads fail to advance clinically because of poor cellular membrane and tissue permeability. Therefore, assessment of the ability of a peptide to cross cellular membranes is critical when developing novel peptide-based therapeutics. Current methods to assess peptide cellular permeability are limited by multiple factors, such as the need to introduce rather large modifications (e.g., fluorescent dyes) that require complex chemical reactions as well as an inability to provide kinetic information on the internalization of a compound or distinguish between internalized and membrane-bound compounds. In addition, many of these methods are based on end point assays and require multiple sample manipulation steps. Herein, we report a novel "Split Luciferin Peptide" (SLP) assay that enables the real-time noninvasive imaging and quantification of peptide uptake both in vitro and in vivo using a very sensitive bioluminescence readout. This method is based on a straightforward, stable chemical modification of the peptide of interest with a D-cysteine tag that preserves the overall peptidic character of the original molecule. This method can be easily adapted for screening peptide libraries and can thus become an important tool for preclinical peptide drug development

A Universal Assay for Aminopeptidase Activity and Its Application for Dipeptidyl Peptidase-4 Drug Discovery

Aminopeptidases, such as dipeptidyl peptidase 4 (DPP-4, CD26), are potent therapeutic targets for pharmacological interventions because they play key roles in many important pathological pathways. To analyze amino-peptidase activity in vitro (including high-throughput screening [HTS]), in vivo, and ex vivo, we developed a highly sensitive and quantitative bioluminescence-based readout method. We successfully applied this method to screening drugs with potential DPP-4 inhibitory activity. Using this method, we found that cancer drug mitoxantrone possesses significant DPP-4 inhibitory activity both in vitro and in vivo. The pharmacophore of mitoxantrone was further investigated by testing a variety of its structural analogues

Prediction of Occult Lymph Node Metastasis in Head and Neck Cancer with CD31 Vessel Quantification.

The management of occult lymph node metastasis (LNM) in head and neck squamous cell carcinoma has been a matter of controversy for decades. The vascular density within the tumor microenvironment, as an indicator of ongoing angiogenesis, could constitute an attractive predictor of LNM. The use of the panvascular endothelial antibody CD31 as a marker of occult LNM has never been reported. The aim of this study was to assess the predictive value of CD31 microvascular density for the detection of occult LNM in squamous cell carcinoma of the oral cavity and oropharynx. Case series with chart review. Tertiary university hospital. Intra- and peritumoral microvascular density values were determined in 56 cases of squamous cell carcinoma of the oral cavity (n = 50) and oropharynx (n = 6) with clinically negative necks using the CD31 marker. Statistical associations of CD31 microvascular densities with clinicopathologic data were then established. Peritumoral CD31 microvascular density was significantly associated with occult LNM in multivariate analysis ( P < .01). Recursive partitioning analysis for this parameter found a cutoff of 19.33, which identified occult LNM with a sensitivity of 91%, a specificity of 65%, a positive predictive value of 40%, a negative predictive value of 97%, and an overall diagnostic accuracy of 71%. Peritumoral CD31 microvascular density in primary squamous cell carcinoma of the oral cavity and oropharynx allows accurate prediction of occult LNM