(7aR,7R)-7-{[(4Z)-5-(2-{[(4Z,8R)-5-(2-amino-1,3-thiazol-4-yl)-2-carboxy-2-methyl-6,9-dioxo-8-[(2R)-7-oxo-2,4,5,7-tetrahydro-1H-furo[3,4-d][1,3]thiazin-2-yl]-4,7-diaza-3-oxanon-4-en-9-yl]amino}-1,3-thiazol-4-yl)-2-carboxy-2-methyl-6-oxo-4-aza-3-oxahex-4-en-6-yl]amino}-6-oxo-3-(pyridin-1-ium-1-ylmethyl)-2,6,7,7a-tetrahydroazeto[2,1-b][1,3]thiazine-4-carboxylate