3-Bromopropylamine hydrobromide reacts with N-hydroxyphthalimide in th
e presence of DBU to give, not the expected N-(3-aminopropyloxy)phthal
imide, but N-(3-aminooxypropyl) phthalimide, 6, formed by an unusual i
ntramolecular rearrangement Coupling-of the pentamethylchroman-6-sulph
onyl (Pmc) derivatives of 9 and 13 with N-Bpoc-aminopropanol affords a
differentially protected 6-oxaspermidine 10 and 6,9-dioxaspermine 14
respectively from which the protecting groups are removed independentl
y.