(7aR,7R)-7-{[(2Z)-2-{2-[(2-{[(2Z)-2-(2-amino-1,3-thiazol-4-yl)-2-(hydroxyimino)acetyl]amino}-2-(4-carboxy-5-vinyl-2H,6H,3H-1,3-thiazin-2-yl)acetyl)amino]-1,3-thiazol-4-yl}-2-(hydroxyimino)acetyl]amino}-6-oxo-3-vinyl-2,6,7,7a-tetrahydroazeto[2,1-b][1,3]thiazine-4-carboxylic acid