01/01/1988 - "This indication has been inferred by studies in tumor-bearing animals, using 19F-NMR spectroscopy determination of tissue fluorospermidine and fluorospermine, formed biochemically from the precursors 2-fluoro or 2,2-difluoroputrescine, and which demonstrate preferential accumulation in tumor versus normal tissue. "
01/01/1988 - "9. From the fact that the accumulation of 6-fluoropolyamines is less selective in tumors than that of 6,6-difluoropolyamines, and from the lower detection sensitivity due to its lower fluorine content, we conclude that 2,2-difluoroputrescine is more advantageous as a tumor marker than 2-fluoroputrescine for detection with 19F-NMR spectroscopy.(ABSTRACT TRUNCATED AT 400 WORDS)"
01/01/1988 - "8. Under identical experimental conditions the accumulation of chain-fluorinated polyamines in tumor tissue was more than twice as high with 2-fluoroputrescine as precursor than with the same dose of 2,2-difluoroputrescine. "