COC(=O)[C@H](N)CCN    mol8521    0_1
COC(=O)[C@H]([NH3+])CCN    mol8521    1_1
COC(=O)[C@H](N)CC[NH3+]    mol8521    1_2
COC(=O)[C@H]([NH3+])CC[NH3+]    mol8521    2_1