6r 7r 7 2 2 aminomethyl phenyl acetyl amino 3 1 carboxymethyl tetrazol 5 yl sulfanylmethyl 8 oxo 5 thia 1 azabicyclo 4 2 0 oct 2 ene 2 carboxylic acid, 7 o aminomethyl phenylacetamido 3 1 carboxymethyl 1h tetrazol 5 yl thio methyl 3 cephem 4 carboxylic acid, 7beta 2 aminomethyl phenyl acetamido 3 1 carboxymethyl 1h tetrazol 5 yl sulfanyl methyl 3 4 didehydrocepham 4 carboxylic acid