<Superscript>99m</Superscript>TcN–gatifloxacin dithiocarbamate complex: a novel multi-drug-resistance <Emphasis Type="Italic">Streptococcus pneumoniae</Emphasis> (MRSP) infection radiotracer

Gatifloxacin (GTN) was derivatized to its dithiocarbamate derivative and its radiolabeling with technetium-99m (^99mTc) using the [^99mTc≡N]²⁺ core was investigated. The appropriateness of the ^99mTcN–gatifloxacin dithiocarbamate (^99mTcN–GTND) complex as a potential multi-drug-resistance Streptococcus pneumoniae (MRSP) infection radiotracer was evaluated in terms of stability in saline, serum, in vitro binding with MRSP and biodistribution in artificially MRSP infected Male Wistar Rats (MWR). In saline the ^99mTcN–GTND complex showed more than 90% labeling yield up to 4 h with a maximum yield of 98.25 ± 0.20%, after reconstitution. In serum the ^99mTcN–GTND complex showed stability up to 16 h of incubation with the appearance of insignificant 15.95% undesirable side products. The ^99mTcN–GTND complex demonstrated saturated in vitro binding with MRSP with a maximum value of 75.50 ± 1.00% (at 90 min). In MWR model of group A, almost six times higher uptake of the labeled GTND was monitored in the muscle of MWR infected with live MRSP as compared to the inflamed and normal muscles. Based on the higher labeling yield in saline, in vitro stability in serum, saturated in vitro binding with live MRSP and promising biodistribution in MWR model we recommend ^99mTcN–gatifloxacin dithiocarbamate complex as a potential MRSP infection radiotracer.     

Kinetics of Reduction of Thionine with Ribose and the Structural Properties of the Dye at Different pH Using DFT Method

The reaction between the thionine (Th) and the ribose was observed spectrophotometrically and changes in absorbance of Th were recorded at variable concentration of dye, reductant and pH. A pseudo first order rate of reaction was found to establish the reduction kinetics of the dye, studied at a pH range of 0.34 to 12.8. Absorption spectrum of Th at different pH, with ribose showed a pH (12.8) dependent introversion. The reduction most probably took place with enediol intermediate of the sugar at high pH. A full geometry optimization of predominant species of Th namely, mono‐deprotonated, di‐deprotonated Th, and LTh (leuco thionine) respectively, at low and high pH, was performed at B3LYP level of theory. The data obtained from the energy minimization were in excellent agreement with other experimental and theoretical observations. The calculated enthalpies of formation for both reduction reactions (mono‐deprotonated Th+H⁺→leucothionine and di‐deprotonated Th+2H⁺→leucothionine) provided evidences for maximum reduction of the dye at high pH.     

Radiosynthesis and characterization of the <Superscript>99m</Superscript>Tc-fleroxacin complex: a novel <Emphasis Type="Italic">Escherichia coli</Emphasis> infection imaging agent

Radiocomplexation of fleroxacin (FXN) with technetium-99m and its characterization in terms of in vitro stability in saline and serum solutions, in vitro binding with live and heat-killed Escherichia coli, and biodistribution in male Wistar rats (MWR) artificially infected with live and heat-killed E. coli was studied. The ^99mTc-FXN complex showed a radiochemical purity (RCP) yield of 98.10 ± 0.24% at 30 min using 125 μg of stannous fluoride, 74 MBq of sodium pertechnetate, and 2 mg of FXN. The complex was found to be more than 90% stable up to 4 h after constitution in normal saline. In serum, the emergence of 16.50% undesirable species was observed within 16 h of incubation at 37 °C. The ^99mTc-FXN complex showed saturated in vitro binding with E. coli with a maximum value of 65.00% at 90 min. A fivefold increase in uptake of the complex was noted in the infected when compared with the inflamed and normal muscle of the MWR infected with live E. coli. The stable radiochemical profile in saline and serum, saturated in vitro binding with E. coli and increased uptake in the infected muscle, confirmed the potential of the ^99mTc-FXN complex as an E. coli infection imaging agent.     

FINITE PERMUTATION REPRESENTATION OF A SUBGROUP OF PICARD GROUP＊

We investigate action of a subgroup G1 of the Picard group on finite sets using coset diagrams.We show that its actions on the sets of 3,4,5,6,8,and 12 elements yield building blocks of Coset diagrams ...     

$$PSL\left( 2,7\right) $$ and carbon allotrope D168 Schwarzite

We investigate actions of the modular group \(PSL(2, \mathbb {Z} )\) on the projective line over finite fields \(PL(\mathbf {F}_{7^{n}})\) and find interesting relation between the coset diagram of orbits and the carbon allotrope with negative curvature D168 Shewarzite. We also highlighted some topological aspects of these diagrams.     

Radiosynthesis and biological evaluation of <Superscript>99m</Superscript>TcN-sitafloxacin dithiocarbamate as a potential radiotracer for <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> infection

Sitafloxacin dithocarbamate (SFDE) was synthesized, radiolabeled with technetium-99m (^99mTc) using [^99mTc-N]²⁺ core and evaluated its biological efficacy as a potential radiotracer for Staphylococcus aureus (S. aureus) infection in artificially infected rats (AIRT) and rabbits (AIRB). The radiochemical stability of the ^99mTc labeled SFDE (^99mTcN-SFDE) in saline and serum was determined by radio-HPLC and TLC methods, respectively. After, 1 min of reconstitution the value of radiochemical purity (RCP) was 99.00 ± 0.20% and was remained more than 90% unwavering even after 240 min of the radiolabeling. The ^99mTcN-SFDE complex showed similar radiochemical permanence behavior in serum at 37 °C. The complex showed almost six fold higher specific in vitro binding with living than heat killed S. aureus. Biodistribution behavior was evaluated in S. aureus AIRT and whole body imaging (WBI) in AIRB, respectively. Seven fold up take was observed in infected muscle of the AIRT as compared to inflamed and normal muscles. The disappearance of activity from blood and appearance in urinary system indicated normal route of excretion of the complex. Scintigraphically, it was confirmed that the labeled SFDE was higher accumulated in the infected muscle higher than in inflamed and normal muscle. The high radiochemical stability in saline and serum, specific in vitro binding with S. aureus, precise in vivo distribution in S. aureus AIRT and targeted WBI in AIRB confirmed the possibility of the ^99mTcN-SFDE complex as a potential and promising S. aureus infection radiotracer.     

Reactions of alkyl hetaryl ketones with carbon tetrachloride under liquid/solid phase-transfer catalysis conditions

Summary Reactions of methyl and ethyl hetaryl ketones in the CCl₄/solid KOH system in the presence of 18 crown-6 at room temperature yield the corresponding 2-hetaryl-2-trichloromethyloxiranes in 8–22% yields. Reactions of sterically hindered ketones of the type (hetaryl)COCHR₂ (R = Me, Et) with CCl₄/OH- form the corresponding a-hydroxy ketones of the type (hetaryl)COC(OH)R₂ in 28–44% yields.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 312–315, March, 1994.     

Thiazole-tethered biaryls as fluorescent chemosensors for the selective detection of Fe3+ ions

3-Amino-5-(thiazol-2-yl)-[1,1′-biaryl]-2,4-dicarbonitriles have been synthesized employing a facile one-pot pseudo four-component domino strategy. All these thiazole-tethered biaryls exhibited blue fluorescence under UV lamp. Based on the high relative quantum yield, three compounds namely, 4a , 4d , and 4i , were chosen to explore the metal interference studies. Against several metal ions, these three thiazole-tethered biphenyl probes were found to be effective fluorescent chemosensors for the selective and sensitive detection of Fe³⁺ ions with a lower detection limit of 0.18, 0.12, and 0.16 μM, respectively.     

Highly active and thermo-stable iminopyridyl vanadium oxychloride catalyzed isoprene polymerization

Stereoregular polymerizations are of high importance, which disclosing the relationships between microstructures and physical properties of polymers. In this contribution, a series of iminopyridyl vanadium oxychloride complexes V1 – V8 (R = H, R¹ = CH₂Ph for V1 ; R = H, R¹ = CHPh₂ for V2 ; R = H, R¹ = octamyl for V3 ; R = H, R¹ = Ph for V4 ; R = H, R¹ = 4-OMe-C₆H₄ for V5 ; R = H, R¹ = 4-CF₃ C₆H₄ for V6 ; R = H, R¹ = 2,4,6-Ph₃ C₆H₂ for V7 and R = Me, R¹ = Ph for V8 ) have been prepared, and were investigated for their catalytic capacity of isoprene polymerization. A single crystal structure of V7′ was reported, which was reduced from V(v) to V(iv) in the oxidation state of vanadium central atom. The catalytic activity was up to 408 kg (mol V)⁻¹ hr⁻¹, when V4 was used. The catalyst V6 was found to be highly thermo-stable with excellent activity even at 100°C. Most importantly, resultant polymers mainly possessed cis-1,4 units (up to 75%) with 25% side-chain 3,4 functional group, which is particularly important component to enhance the application of these synthetic rubbers.