Year of Publication
Arts and Sciences
David A. Atwood
There is a continued interest in the properties of arsenic thiolate compounds for both industrial and biological uses. Recent discoveries in the medicinal properties of such compounds have resulted in a sustained need for the synthesis of new dithiarsolane compounds for research as anti-leukemic compounds. Close analogues of the 2-halo arsenic dithiolates, namely those with an arsenic-carbon bond instead of an arsenic-halide bond, have recently been shown to have some efficacy towards leukemia cells. Based on the hydrolytic character and the active role of glutathione with arsenic in vivo, the compounds reported here may also have such activity. Arsenic compounds have demonstrated biological activity in the literature, thus the hypothesis of this thesis is cyclized arsenic thiolates can be synthesized with the appropriate characteristics as to be potentially useful medicinal agents as well as provide new structural and reaction information. A series of arsenic and antimony di- and trithiolates has been synthesized and characterized. Those compounds include 2-chloro-1,3,2-dithiarsolane, 2-bromo- 1,3,2-dithiarsolane, 2-iodo-1,3,2-dithiarsolane, 2-chloro-1,3,2-dithiarsenane, 2-bromo- 1,3,2-dithiarsenane, 2-iodo-1,3,2-dithiarsenane, 3-chloro-4H,7H-5,6-benz-1,3,2- dithiarsepine, 2-chloro-benzo-1,3,2-dithiarsole, 1,2-bis-dithiarsolan-2-ylmercapto-ethane, tris-(pentafluorophenylthio)-arsen, bis(2-(1,3,2-benzodithiarsol-2ylsulfanyl)- benzenesulfide), 2-chloro-benzo-1,3,2-dithiastibole, and bis(2-(1,3,2-benzodithistibol)- 1,2-benzenedithiol. Elucidation of the pH characteristics of arsenic dithiolates within the human toxicity reaction pathway is an area of interest. It has been shown that the aqueous arsenic dithiolate stability depends on the size of the ring. 2-Chloro-1,3,2-dithiarsolane has been shown to be somewhat stable at both low and high pH as well as neutral pH. 1,2-bis- Dithiarsolan-2-ylmercapto-ethane is completely stable in a neutral aqueous solution. Glutathione does not permanently bind to arsenic even in overwhelming excess. In particular, these fully characterized compounds determine how reactive the AsS and AsCl linkages are under environmental and biological conditions, and provide a source of new reagents to examine in medical applications. Future applications may include the incorporation of the reported compounds in filtration and remediation technologies with further modification.
Shaikh, Taimur A., "NEW DEVELOPMENTS IN CYCLIZED ARSENIC AND ANTIMONY THIOLATES" (2007). University of Kentucky Doctoral Dissertations. 494.