Physical Sciences and Mathematics Commons^™

Synthesis Of Multisubstituted Halo-Olefins Via Pd-Catalyzed Cross-Coupling Reactions : Applications In Nucleoside Chemistry, Daniela Andrei

FIU Electronic Theses and Dissertations

The enzyme S-adenosyl-L-homocysteine (AdoHey) hydrolase effects hydrolytic cleavage of AdoHcy to adenosine (Ado) and L-homocysteine (Hcy). The cellular levels of AdoHcy and Hcy are critical because AdoHcy is a potent feedback inhibitor of crucial transmethylation enzymes. Also, elevated plasma levels of Hcy in humans have been shown to be a risk factor in coronary artery disease.

On the basis of the previous finding that AdoHcy hydrolase is able to add the enzyme-sequestered water molecule across the 5',6'-double bond of (halo or dihalohomovinyl)-adenosines causing covalent binding inhibition, we designed and synthesized AdoHcy analogues with the 5',6'-olefin motif incorporated in place of …

Syntheses Of Aza Analogs Of Kainoids, Mingping Di

FIU Electronic Theses and Dissertations

The kainoids are a class of non-proteinogenic pyrrolidine dicarboxylates that exhibit both excitatory and excitotoxic activities. These activities are a result of the ability of the kainoids to act as glutamate receptor agonists by activating ionotropic glutamate receptors. The parent of this group of compounds is x-kainic acid. Kainic acid is isolated from the seaweed Diginea simplex and has been used in Asian countries as a treatment for intestinal worms in children. In addition it is used extensively by neuropharmacologists for the study of glutamate receptors. Several years ago, the world's sole supplier of kainic acid discontinued this product. Since …

Natural Organic Matter And Colloid-Facilitated Arsenic Transport And Transformation In Porous Soil Media, Zhangrong Chen

FIU Electronic Theses and Dissertations

Prediction of arsenic transport and transformation in soil environment requires understanding the transport mechanisms and proper estimation of arsenic partitioning among all three phases in soil/aquifer systems: mobile colloids, mobile soil solution, and immobile soil solids. The primary purpose of this research is to study natural dissolved organic matter (DOM)/colloid-facilitated transport of arsenic and understand the role of soil derived carriers in the transport and transformation of both inorganic and organoarsenicals in soils.

DOM/colloid facilitated arsenic transport and transformation in porous soil media were investigated using a set of experimental approaches including batch experiment, equilibrium membrane dialysis experiment and column …

Reactions Of 1,1-Disubstituted-Ethylenes And 1,4-Diphenyl-1,3-Butadienes With Singlet Oxygen And 4-Alkyl-1,2,4-Triazoline-3,5-Dione (Rtad), Baishakhi Das

FIU Electronic Theses and Dissertations

A study of the reaction pathways of 1,1-diphenylethylene; methyleneindan; fluorenene; trans,trans-1,4-diphenyl-1,3-butadiene; cis,trans-1,4-diphenyl-1,3- butadiene and cis,cis-1,4-diphenyl-1,3-butadiene with singlet oxygen and the singlet oxygen mimic, 4-alkyl-1,2,4-triazoline-3,5-dione (RTAD) has been undertaken. Comparisons of the reactivity and reaction mechanisms among the isomers and electrophiles have been conducted. Singlet oxygen exhibits significantly lower reactivity compared to RTAD. RTAD reacts with 1,1- diphenylethylene to produce 4+2/ene and 4+2/4+2 (2:1) adducts but with methyleneindan to give a complex mixture including the ene adduct. Reactions of isomeric 1,4-diphenyl-1,3-butadienes with RTAD produce 4+2 adducts. The results of the studies provide …