RB6 rb6 (2R)-2-[(1R)-1-{[(2Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(hydroxyimino)acetyl]amino}-2-oxoethyl]-5-({2-oxo-1-[(3R)-pyr rolidin-3-yl]-2,5-dihydro-1H-pyrrol-3-yl}methyl)-3,6-dihydro-2H-1,3-thiazine-4-carboxylic acid RB6