Wenderoth, Lind & Ponack
Penicillin oxides
 Compounds of the formula: ##STR1## (where COB is carboxy or protected carboxy and X is hydrogen or nucleophilic group) preparable by oxidation of the corresponding N-nitrosopenicillin derivatives are useful as starting materials for synthesizing known and useful cephalosporins. 
Shionogi & Co., Ltd.
C
C07D
inventional
Shoichiro Hikaru Tsutomu Teruji Wataru
Uyeo Itani Aoki Tsuji Nagata