“…This new base, N -formamidino-N'-(3-aminopropyl)-1,4-diaminobutane, or guanylspermidine (170), has been previously isolated from leeches and marine worms together with its related putrescine and cadaverine analogues (379)(380)(381)(382)(383)(384)(385)(386)(387)(388)(389). This new base, N -formamidino-N'-(3-aminopropyl)-1,4-diaminobutane, or guanylspermidine (170), has been previously isolated from leeches and marine worms together with its related putrescine and cadaverine analogues (379)(380)(381)(382)(383)(384)(385)(386)(387)(388)(389).…”