N. Goudgaon, Y. El-Kattan, Xiao-Er Xia
Dec 1, 1997
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0
Influential Citations
9
Citations
Journal
Nucleosides, Nucleotides & Nucleic Acids
Abstract
Abstract Previous biochemical and pharmacological studies indicated that 5-o-carboranyl-2′-deoxyuridine is a lead candidate for boron neutron capture therapy. This prompted the development of a rapid and stereoselective N 1-glycosylation reaction of silylated 5-o-carboranyluracil with a variety of protected sugars. The key intermediate, 5-o-carboranyluracil (6), was prepared from 5-iodouracil in six steps. A novel coupling procedure of the 2,4-dimethoxy-5-ethynylpyrimidine (4) with decaborane without activator was used. Silylated 6 was coupled with a variety of carbohydrates under mild conditions to produce several carborane containing nucleosides. In each case, the stereochemistry and stereoselectivity of the glycosylation reaction was not affected by the presence of the carborane at the 5-position of the uracil and produced exclusively closo [closo-1,2-C2B10H12 cage] nucleosides. This was confirmed by X-ray structure determination of racemic 5-carboranyl-2′,3′-dideoxy-3′-thiauridine. This compound demon...