(2R)-3-{[(7aR,7R)-7-{[(3Z)-4-(2-furyl)-5-oxo-3-aza-2-oxapent-3-en-5-yl]amino}-3-[(carbamoyloxidanyl)methyl]-6-oxo-2,6,7,7a-tetrahydroazeto[2,1-b][1,3]thiazin-4-yl]carbonyl}-5-[(carbamoyloxidanyl)methyl]-2-[(3E,7R)-7-carboxy-4-(2-furyl)-3,6-diaza-2-oxahept-3-en-7-yl]-6H,2H,3H-1,3-thiazine-4-carboxylic acid