Synthetic Molecules That Specifically React with Target Sequences

Patent Synthetic Molecules That Specifically React with Target Sequences 

Tsien etal, US Patent 6,008,378 (December 28, 1999) Assignee The Regents of the University of California Utility DNA Labeling Agents 

4 5 -Bis(2-arsa-l,3-dithiolan-2-yl)-fluorescein is a non-fluorescing chemical agent. In the presence of at least 10 or more sequenced amino acids, four of which must consist of cysteine, it forms a fluorescent red shift complex. 

In a subsequent investigation by the author (1) the biotin conjugate (I), of Step 1 was prepared. 

The Step 1 dichloro derivative, 2, 7 -dichloro-4, 5 -bis(2-arsa-,3-dithiolan-2-yl)fluorescein, (II), product was also prepared by the author as illustrated in Eq. 1  

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