6-(.alpha.-3-Acyl-ureidoacetamido)-penicillanic acids and pharmaceutically acceptable non-toxic salts thereof in which the hydrogen atom of the nitrogen atom present in the 3-position is substituted, are effective against Gram-positive and Gram-negative infections, particularly Klebsiella aerobacter infections.
                            6-(α-3-酰基-
尿素乙酰基)-青霉烷酸及其药学上可接受的无毒盐,其中3位氮原子上的氢原子被取代,对革兰氏阳性和革兰氏阴性感染有效,尤其是对克雷伯氏菌感染有效。