With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Raccoons originally inhabited mixed bags.
text_B: Tambjamines are a group of natural products that are structurally related to prodiginines and are characterized by a 4-methoxy-2 ,2 ' - bipyrrolenamine structure .. Tambjamines are composed of two pyrrole rings with an enamine moiety at C-5 and a methoxy group at C-4 , and the majority have short alkyl chains substituted for the enamine nitrogen .. pyrrole. pyrrole. methoxy group. methoxy group. This group of alkaloids have been isolated from marine invertebrates and bacteria -LRB- both marine and terrestrial -RRB- .
not_related.