Abstract: There is provided a method by which various compounds (1) having a carboxyl group in the molecule have the carboxyl group converted to a (dioxolenon-4-yl)methyl ester at low cost, in a simple way and at high yield. The process for producing compounds of formula (3) according to the reaction scheme shown below comprises reacting carboxylic acids of formula (1) with 4-chloromethyldioxolenone compounds of formula (2) in a solvent in the presence of both a phase transfer catalyst and a metal iodide: [where Q represents an organic group, M represents a hydrogen atom, an alkali metal, an alkaline earth metal or a transition metal, R1 and R2 represent a hydrogen atom, an optionally substituted (C1-6 alkyl group or phenyl group)].

Abstract: Processes for preparing compounds having two or three antibiotic functionalities using quinolone derivatives, &bgr;-lactams and vancomycin and the like as the starting materials and chloride linking agents; and the novel compounds prepared by these processes, are disclosed.

Abstract: This invention provides a method of producing a .beta.-lactam derivative represented by the formula (I): ##STR1## said method consisting essentially of the step of reacting a .beta.-lactam derivative represented by the formula (II): ##STR2## with a phenol in a reaction system which consists essentially of said .beta.-lactam derivative of formula (II) and said phenol.

Abstract: A pharmaceutical compound which comprises reacting the sodium penicillanic acid 1,1-dioxides with chloroiodomethane in the presence of a solvent to produce chloromethylpenicillanate 1,1-dioxides, reacting the chloromethylpenicillanate 1,1-dioxides with a sodium iodide to produce iodomethylpenicillanate 1,1-dioxides, and reacting the iodomethylpenicillanate 1,1-dioxide with sodium methampicillin and is effective in the treatment of bacterial infections in a mammal.

Abstract: An improved process for the production of penicillic acid compounds, especially chloromethyl ester of penicillin G, penicillin V or sulbactam is disclosed.

Abstract: Process for the preparation of 1'-ethoxy carbonyloxy ethyl esters of penicillins, wherein a compound of the formula ##STR1## in which A is phenyl, phenoxy or 4-hydroxyphenyl, B is hydrogen, an amino group or a protected amino group and Z is hydrogen or a cation selected from the group of alkali metal, tri (lower alkyl ) ammonium and tetra (lower alkyl) ammonium, is reacted with 1-bromoethyl ethyl carbonate in an organic solvent and when B is a protected amino group the protecting group is split off to yield a primary amino group.There are also provided novel compounds of the formula ##STR2## in which Ph is phenyl and R is CH.sub.3 -- or C.sub.2 H.sub.5 --.

Abstract: 6-Halo- and 6,6-dihalo-1,1-dioxopenicillanoyloxymethyl 6-[D-2-(2-alkoxycarbonyl-1-methylvinylamino- and 1-methyl-3-oxo-1-butenylamino)-2-phenylacetamido]penicillanates and analogs; process for their conversion to sultamicillin and analogs; and process for their preparation.

Abstract: The present invention relates to hitherto unknown compounds of the general formula I: ##STR1## in which R.sub.1 stands for a phenyl, 4-hydroxyphenyl, 1,4-cyclohexadienyl or a 3-thienyl group; R.sub.2 represents a primary amino or a carboxy group; R.sub.3 is a hydrogen atom, or a lower alkyl, aryl or aralkyl radical, and A stands for a radical of a .beta.-lactamase inhibitor containing a .beta.-lactam ring as well as a carboxy group, A being connected via the carboxy group.The present invention provides new compounds useful in the treatment of bacterial infections. The new compounds are in particular strongly active against .beta.-lactamase producing bacteria.

Abstract: The novel compound .alpha.-bromodiethylcarbonate, novel methods for the preparation thereof, its use in the preparation of 1-ethoxycarbonyloxyethyl esters of penicillins and cephalosporins, and improvements in the method for preparing such esters.

Abstract: The novel compound .alpha.-bromodiethylcarbonate, its use in the preparation of 1-ethoxycarbonyloxyethyl esters of penicillins and cephalosporins, in particular bacampicillin, and improvements in the method for preparing such esters.