Mustafa Emrullahoğlu

Manganese(III) acetate-mediated oxidative coupling of phenylhydrazines with furan and thiophene: a novel method for hetero biaryl coupling

Abstract A convenient new method for the arylation of furan and thiophene with arylhydrazine and manganese(III) acetate is described. Oxidation of arylhydrazines with Mn(III) acetate in furan or thiophene affords the corresponding 2-aryl-substituted furans and thiophenes in good yield using commercially available materials; access to 2-substituted heterobiaryls works selectively, and coupling occurs with loss of the hydrazine moiety.

A BODIPY-based reactive probe for the detection of Au(III) species and its application to cell imaging

A BODIPY-based fluorescent probe bearing a pyridyl hydrazone motif responds selectively to Au(III) ions through an irreversible C=N bond hydrolysis reaction.

A BODIPY-based fluorescent probe for the differential recognition of Hg(II) and Au(III) ions

We describe the design, synthesis and spectral behaviour of a fluorescent molecular sensor able to recognize Hg2+ and Au3+ ions via different emission modes. The molecular sensor is constructed on a single BODIPY dye appended with a semithio-carbazone functionality as a recognition motif.

Darzens Reaction of Acyl Phosphonates with α-Bromo Ketones: Selective Synthesis of cis- and trans-Epoxyphosphonates

Acyl phosphonates with alpha-halo ketones in the presence of bases at room temperature afford cis- and trans-epoxyphosphonates in good chemical yields and high selectivities using different bases. The diastereoselectivity of this reaction is easily controlled by changing the base. Changing the base from Cs2CO3 to DBU changed the diastereomeric ratio (trans/cis) from 3/2 to 9/1. Moreover, the treatment of the trans isomer with DBU showed a complete conversion to the corresponding cis isomer.

A Ratiometric Fluorescent Probe for Gold and Mercury Ions

A fluorescent probe that displays a ratiometric fluorescence response towards gold and mercury ions has been devised. Emitting at a relatively longer wavelength, the conjugated form of the fluorescent dye transforms in the presence of the gold or mercury ions into a new dye, the molecular structure of which lacks the conjugation and consequently emits at a distinctly shorter wavelength.

A BODIPY-based fluorescent probe for ratiometric detection of gold ions: utilization of Z-enynol as the reactive unit.

Using an irreversible intramolecular cyclisation pathway triggered by gold ions, a boron-dipyrromethene (BODIPY) based fluorescent probe integrated with a reactive Z-enynol motif responds selectively to gold ions. With the addition of gold(iii), the probe displays ratiometric fluorescence behaviour clearly observable to the naked eye under both visible and UV light.

BODIPY–Au(I): A Photosensitizer for Singlet Oxygen Generation and Photodynamic Therapy

Upon complexation with Au(I), a photoinactive BODIPY derivative was transformed into a highly photoactive triplet sensitizer. Along with high efficiency in singlet oxygen generation (ΦΔ = 0.84), the new BODIPY-Au(I) skeleton showed excellent photocytotoxic activity against cancer cell lines (EC50 = 2.5 nM).

A BODIPY/pyridine conjugate for reversible fluorescence detection of gold(III) ions

We designed a “turn-on” type fluorescent probe based on a BODIPY–pyridine conjugate which exhibits high selectivity towards Au(III) ions and, also responds to changes in the pH within the acidic pH range. The probe offers features such as a rapid response time, a low detection limit, and high sensitivity and selectivity. The detection of Au(III) is recognized by a distinct change in the emission intensity which relies on a reversible “ligand to ion” binding mechanism. We also document the utility of the probe for the quantification of gold ion residues in synthetic end products prepared via gold catalysis.

A guanidinium modified rhodamine-based fluorescent probe for in vitro/vivo imaging of gold ions

We devised a rhodamine-based fluorescent probe functionalized with a guanidinium moiety, which both operates efficiently in pure aqueous media and displays a selective fluorescence response to Au3+ ions. We also demonstrated the successful fluorescence imaging of Au3+ within living cells and a vertebrate species, the zebrafish.

Sol-gel Approaches for Elaboration of Polyol Dehydrogenase-Based Bioelectrodes

Abstract This review describes the input of sol-gel chemistry to the immobilization of polyol dehydrogenases on electrodes, for applications in bioelectrocatalysis. The polyol dehydrogenases are described and their application for biosensing, biofuel cell and electrosynthesis are briefly discussed. The immobilization of proteins via sol-gel approaches is described, including a discussion on the difficulty to maintain the activity of proteins in a silica matrix and the strategies developed to offer a proper environment to the proteins by developing optimal organic-inorganic hybrid materials. Finally, the co-immobilization of the NAD+ co-factor and of mediators for the elaboration of reagentless devices is presented, based on published and original data. All-in-all, sol-gel approaches appear to be a very promising for development of original electrochemical applications involving dehydrogenases in near future.