“…(Hertzberg & Dervan, 1984; Tullius & Dombroski, 1985; Sigman, 1986; Barton, 1986; Stubbe & Kozarich, 1987; Goyne & Sigman, 1987;Tullius, 1989). In some cases photochemical activation of the cleavage reaction has also been exploited (see, e.g., Freifelder et al, 1961; Friedman & Brown, 1978; Subramanian & Meares, 1985; Fleisher et al, 1986; Blacker et al, 1986; Ward et al, 1986;Buchardt et al, 1987; Nielsen et al, 1988a-c;Jeppesen et al, 1988; Behr, 1989; Veal & Kill, 1988; Jeppesen & Nielsen, 1989a,b; Uchida et al, 1989).…”