. . "rocyclic base with a carbon to carbon bond; each of m and q is independently 0 to 8, inclusive; r is 0 or 1, and each of R4 and R6 is independently H, OR, SR, NHOR, NH2, or NH(CH2)t NH2 where R is H or C1-6 alkyl and t is an integer from 0 to 12. 14." . . .