Regular tissue suggests that itReceived: December 29, 2012 Revised: March 9, 2013 Published: March 15,dx.doi.org/10.1021/bc300693w | Bioconjugate Chem. 2013, 24, 712-Bioconjugate ChemistryArticleFigure 1. Fluorescent COX-2 probes. Carboxylic acid containing core NSAIDs, COXIBs, or their derivatives were applied as creating blocks for conjugate chemistry. These compounds have been tethered via a series of alkyl, piperazine, along with other linkers to a diverse selection of fluorophore moieties to synthesize fluorescent conjugates as COX-2-selective fluorescent imaging agents.is an perfect target for molecular imaging by radiolabeled or fluorescent COX-2 inhibitors. To test this hypothesis, we as well as other laboratories have studied imaging of COX-2 expression in inflammation and cancer making use of 123I- or 18 F-labeled COX-2 selective inhibitors.22-26 In addition, we lately described a conjugate-based conversion of the nonsteroidal anti-inflammatory drug (NSAID), indomethacin, into fluorescent carboxy-X-rhodamine (ROX) conjugates which are capable of inhibiting COX-2 selectively and potently in each purified protein and intact cells. These conjugates, which don’t substantially inhibit COX-1, enabled the optical imaging of COX-2 in inflammatory lesions and COX-2-expressing tumors in vivo.27 The present paper describes the details of your structure-activity relationship (SAR) studies performed for optimization of those lead compounds from a wide selection of fluorescent conjugates of NSAIDs or COX-2-selective inhibitors (COXIBs). The conjugates had been evaluated as COX-2-targeted imaging agents, and active molecules were validated in vitro and in vivo as COX-2-targeted agents in cells and tumors. The results present vital background and additional assistance for our previous report,27 which reveals the initial fluorescently labeled optical imaging agent validated for COX-2-targeted in vivo imaging of inflammation and cancer.EXPERIMENTAL PROCEDURES Chemistry. Standard strategies had been utilized for the synthesis of fluorescent derivatives of NSAIDs and COXIBs. A wide range of carboxylic acid-containing core compounds (e.g., indomethacin, an iodoindomethacin, an indolyl carboxamide analog of indomethacin (reverse indomethacin), flurbiprofen, ketoprofen, or maybe a carboxylic acid derivative of celecoxib) had been tethered via a series of alkyl, aryl piperazinyl, or polyethylene glycol linkers to a diverse range of bulky organic fluorophore moieties. The fluorophores incorporated dansyl, dabsyl, coumarin, fluorescein, rhodamine, alexa-fluor, nile blue, cy5, cy7, close to IR, and IR dyes, too as some lanthanide chelators (Figure 1).Gallamine Triethiodide Technical Information Synthetic procedures, in addition to analytical and spectroscopic characterization of all compounds, are described in Supporting Info.(S)-Mephenytoin MedChemExpress Fluorometry.PMID:23771862 Steady state fluorescence excitation and emission spectra were determined for each compound with a Spex 1681 Fluorolog spectrofluorometer, equipped with a 450 W xenon arc lamp. The excitation and emission monochromator slit widths had been 1-2 mm. The solvent employed was pH 7 buffer. Inhibition Assay Using Purified COX-1 and COX-2. Inhibition of purified ovine COX-1 or mouse COX-2 by test compounds was assayed by a previously described strategy,27 which quantifies the conversion of [1-14C]arachidonic acid todx.doi.org/10.1021/bc300693w | Bioconjugate Chem. 2013, 24, 712-Bioconjugate Chemistry [1-14C]prostaglandin products. Reaction mixtures of 200 L consisted of hematin-reconstituted protein in one hundred mM TrisHCl, pH eight.0, 500.