1: 6-[5-(2-oxohexahydrothieno[3,4-d]imidazol-6-yl)pentanoylamino]hexanoic acid With N,N,N',N'-tetramethyl-O-(N-succinimidyl)uronium tetrafluoroborate; N-ethyl-N,N-diisopropylamine in water; N,N-dimethyl-formamide T=20°C; 0.333333 h; 2: 6-amino-hexanoic acid in water; N,N-dimethyl-formamide 1 h; 3: With hydrogenchloride in ethanol; water T=4°C; 20 h;