0  B1R0.1  CN 593-51-1 [0,1,0,0,0,0|0,0,0]=1
1  B2R0.1  CNC 506-59-2 [0,2,0,0,0,0|0,0,0]=2
2  B2R0.1  NC=O 75-12-7 [0,2,0,0,0,0|0,0,0]=2
3  B2R0.1  O=C[O-] 540-69-2 [0,2,0,0,0,0|0,0,0]=2