[{"from": "human", "value": "Describe this molecule. [C][C][=Branch1][C][=O][C][=N][C][=C][Branch1][O][N][C][=Branch1][C][=O][N][C][Ring1][#Branch1][=O][N][C][C][C][O]"}, {"from": "gpt", "value": "The molecule is a nucleobase analogue that is uracil substituted with a (3-hydroxypropyl)amino group at position 6 and an (E)-(2-oxopropylidene)amino group at position 5; one of 20 modifications to the potent microbial riboflavin-based metabolite antigen 5-(2-oxopropylideneamino)-6-D-ribityl aminouracil (5-OP-RU), an activator of mucosal-associated invariant T (MAIT) cells when presented by the MR1 protein (reported in MED:32123373). It has a role as an epitope. It is a pyrimidone and a nucleobase analogue. It is functionally related to a uracil."}]