Abstract: Compounds of the formula ##STR1## wherein X is --O--or --S--;R.sup.1 is amino or a substituted amino group;R.sup.2 is carboxy or a protected carboxy group; and the heavy solid line means single or double bond; the compounds are useful in the treatment of infectious diseases particularly fungal infection, in human beings and animals.

Abstract: A process for preparing an azetidinone of the formula: ##STR1## which comprises reacting a C-unsubstituted methyleneamine of the formula: ##STR2## with R.sup.2 --CH.sub.2 COOH, its acid halide or anhydride, in the presence of boron trihalide and an organic base, wherein R.sup.1 is an organic residue bearing a carboxy group or its derivative and R.sup.2 is azido, substituted amino, halogen, acyloxy, alkoxy, aryloxy or aralkoxy.

Abstract: Substituted phenylacetic acid compounds represented by the following general formula and preparation thereof: ##STR1## wherein R.sup.1 is hydrogen or protected carboxy,R.sup.2 is hydrogen, or protected amino, provided that when R.sup.1 is hydrogen, then R.sup.2 is protected amino, and when R.sup.2 is hydrogen, then R.sup.1 is protected carboxy,R.sup.3 is oxo, hydroxyimino or protected hydroxyimino,R.sup.4 is hydrogen or halogen, andm is an integer of 1 to 3.

Abstract: Cephalosporin analogues represented by the formula ##STR1## wherein R.sup.1 is amino or a substituted amino,R.sup.2 is carboxy or a protected carboxy, andR.sup.3 is hydrogen or lower alkoxy, processes for making the same, azetidinone intermediates and pharmaceutical compositions comprising said cephalosporin analogues as active ingredients.

Abstract: New hydroxyaminohydrocarbonphosphonic acid derivatives of the formula: ##STR1## wherein R.sup.1 is hydrogen or acyl,R.sup.2 is hydrogen, lower alkyl, ar(lower)alkyl or acyl, andA is lower alkylene, lower alkenylene or hydroxy(lower)alkylene,or the esters at the phosphono group thereof or the pharmaceutical acceptable salt thereof, and production and use thereof.

Abstract: Hydroxyaminohydrocarbonphosphonic acid derivatives represented by the formula: ##STR1## wherein R.sup.1 is hydrogen or acyl,R.sup.2 is hydrogen, lower alkyl, ar(lower) alkyl or acyl, andA is lower alkylene, lower alkenylene or hydroxy(lower) alkylene, or the esters at the phosphono group thereof or the pharmaceutically acceptable salts thereof, excepting 3-(N-acetyl-N-hydroxyamino) propylphosphonic acid, 3-(N-acetyl-N-hydroxyamino)-2-hydroxypropylphosphonic acid, and their pharmaceutically acceptable salts, and processes for preparing the same.Included are compounds having antimicrobial activity against various pathogenic organisms.

Abstract: This invention relates to new 2-azetidinone compounds, which have antimicrobial activities, and to processes for the preparation thereof, and more particularly, this invention provides new 2-azetidinone compounds, especially ones having various substituted carboxyalkyl radicals at the first position and having various groups at the fourth position of the azetidinone nucleus, which have antimicrobial activities against various pathogenic microorganisms and are useful as antibiotics in treatment for microbial infections in mammal including human being and animals.