Physical Sciences and Mathematics | Open Access Articles

Quantitative Footprinting Analysis. Binding To A Single Site, Robert Rehfuss, Jerry Goodisman, James C. Dabrowiak

Chemistry - All Scholarship

The theory for measuring ligand binding constants from footprinting autoradiographic data associated with a single binding site is derived. If the ligand and DNA cleavage agent compete for a common site, the spot intensities are not proportional to the amount of DNA not blocked by ligand. The analysis of a single site is experimentally illustrated by using results for the anticancer drug actinomycin D interacting with the duplex d(TAGCGCTA)2 as probed with the hydrolytic enzyme DNase I.

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Synthesis Of Highly-Strained Gem-Difluoro Compounds By Reaction Of Difluoromethylene With Cycloalkenes, Deyi Yang

Theses

Trans-Cyclooctene is thought to be more reactive than cis-cyclooctene due to its trans-structure. When cis or trans-clooctene reacts with difluormethylene (:CF₂), trans-9,9-difluorobicyclo[ 6,1,0] nonane was generated in much higher yield than cis-9,9-difluorobicyclo[6,1,0]nonane. [PhCF₃P⁺CF₂Br]Br^- was chosen to be the difluoromethylene precursor in this study. The reason was that the reaction condition for trans-cyclooctene and :CF₂ should be at low temperature. Only [PhCF₃P⁺CF₂Br]Br^- could generate CF₂ at lower temperature (e.g. room temperature). We succeeded in the synthesis of trans-9,9-difluorobicyclo[6,1,0]nonane and its cis isomer and …