Compounds of formula (I): ##STR1## (wherein R.sup.1 represents hydrogen or a hydroxy-protecting group, R.sup.2 and R.sup.3 represent hydrogen, alkyl or aryl; R.sup.4 represents optionally substituted alkyl, alicyclic heterocyclic, aryl, aromatic heterocyclic, optionally substituted alkenyl or optionally substituted alkynyl; R.sup.5 represents hydrogen or a carboxy-protecting group; and R.sup.6 represents alkoxy, aryloxy, dialkylamino or diarylamino or two or R.sup.6 together represent o-phenylenedioxy or three together represent CH.sup.3 C(--CH.sub.2 O--).sub.3) may be prepared by reacting the corresponding carbonyl compound with a compound of formula P(R.sup.6).sub.3. Compounds (I) may be cyclised to prepare carbopenem derivatives, many of which have valuable antibiotic activity.
式(I)的化合物:##
STR1##(其中R.sup.1代表
氢或羟基保护基,R.sup.2和R.sup.3代表
氢、烷基或芳基;R.sup.4代表可选择取代的烷基、脂环杂环、芳基、芳香杂环、可选择取代的
烯基或可选择取代的炔基;R.sup.5代表
氢或羧基保护基;R.sup.6代表烷
氧基、芳
氧基、二烷基
氨基或二芳基
氨基,或两个R.sup.6一起代表o-
苯二
氧基,或三个一起代表CH.sup.3 C(--CH.sub.2 O--).sub.3)可以通过将相应的羰基化合物与式P(R.sup.6).sub.3的化合物反应来制备。化合物(I)可以环化以制备羧基
青霉素衍
生物,其中许多具有有价值的
抗生素活性。