Medicine and Health Sciences Commons^™

Design And Synthesis Of S-Ribosylhomocysteine Analogues, Christiane Chbib

FIU Electronic Theses and Dissertations

Bacteria are known to release a large variety of small molecules known as autoinducers (AI) which effect quorum sensing (QS) initiation. The interruption of QS effects bacterial communication, growth and virulence.

Three novel classes of S-ribosylhomocysteine (SRH) analogues as potential inhibitors of S-ribosylhomocysteinase (LuxS enzyme) and AI-2 modulators of QS were developed. The synthesis of 2-deoxy-2-bromo-SRH analogues was attempted by coupling of the corresponding 2-bromo-2-deoxypentafuranosyl precursors with the homocysteinate anion. The displacement of the bromide from C2 rather than the expected substitution of the mesylate from C5 was observed. The synthesis of 4-C-alkyl/aryl-S-ribosylhomocysteine analogues involved the following steps: …

Design And Synthesis Of 4-N-Alkanoyl And 4-N-Alkyl Gemcitabine Analogues Suitable For Positron Emission Tomography, Jesse E. Pulido

FIU Electronic Theses and Dissertations

Gemcitabine is a highly potent chemotherapeutic nucleoside agent used in the treatment of several cancers and solid tumors. However, it is therapeutically limitated because of toxicity to normal cells and its rapid intracellular deamination by cytidine deaminase into the inactive uracil derivative. Modification at the 4-(N) position of gemcitabine's exocyclic amine to an -amide functionality is a well reported prodrug strategy which has been that confers a resistance to intracellular deamination while also altering pharmacokinetics of the parent drug. Coupling of gemcitabine to carboxylic acids with varying terminal moieties afforded the 4-N-alkanoylgemcitabines whereas reaction of 4-N …