Harrington F P, Knott S J, O'Hanlon P J, Southgate R
Beecham Pharmaceuticals, Chemotherapeutic Research Centre, Surrey, UK.
J Antibiot (Tokyo). 1989 Aug;42(8):1241-7. doi: 10.7164/antibiotics.42.1241.
The structure-activity relationships within a series of penicillins and cephalosporins containing an N(4)-substituted piperazine-2,3-dione moiety in the C(6)/C(7)-beta-side chain are discussed.