Table 1.

Linker structures and % yield (for two steps) for the synthesis of dimeric neomycins.

Neomycin dimer	Linker length	Structure of the linker (-x-, from Scheme 1 and Scheme 2)	% yield
DPA51	7		89.5
DPA52	7		88.2
DPA65	7		83.0
DPA53	8		87.0
DPA54	8		88.5
DPA55	14		82.0
DPA56	14		88.8
DPA58	20		83.5
DPA60	24		82.8