N, N′-Bis (p-tolylsulfonyl)-α-ω-alkanediamine disodium salts (n= 3, 4, 5, 6, 7, 8, 9, 10) were subjected to monopyridylmethylation by the reaction with 5′-deoxy-5′-chloro-or 5′- deoxy-2′-chloro-3, 4′-O-isopropylidenepyridoxine hydrochloride, accompanied by the corresponding bispyridylmethylation. Monopyridylmethylation became remarkable for longer methylene chains of the diamine. Thus, introduction of an amino group protected by a ...