As part of a program to synthesize biologically interesting polyamines and their conjugates, we report studies on the structure and reactivity of hydroxyputrescinealdehyde adducts which permit regioselective functionalization of this rather rare naturally occurring diamine. When reacted with p-nitrobenzaldehyde (2 equiv) in CHCl,, 1 forms predominantly 6b (as well aa 5b and 7b) in an equilibrium which is highly solvent dependent. The results of ...
