Abstract: There are provided compounds I ##STR1## wherein A is a hydrogen atom or an organic group,R.sub.1 is hydrogen or halogen atom or an organic group,R.sub.2 is hydrogen or halogen atom, C.sub.1 -C.sub.4 alkyl or acyloxy group,R.sub.3 is hydrogen atom, C.sub.1 -C.sub.4 alkyl or alkoxy, benzyl group or a methylene andR.sub.4 is chloro, fluoro, hydrogen atom or an organic group.The compounds I are elastase inhibitors. A process for their preparation is also provided, as are pharmaceutical compositions containing them.

Abstract: Cephalosporins of the formula (I): ##STR1## wherein m is one or two; n is zero, one or two; A and B are organic residues; and R.sub.1 and R.sub.2 are halogen or hydrogen atoms or organic groups are endowed with elastase inhibitory activity. Two processes for their preparation starting from the corresponding 4-acyl cephem are also provided.

Abstract: There is provided a process for preparing a compound of the formula (I): ##STR1## wherein R.sub.1 is an organic residue, R.sub.2 is a hydrogen or a chlorine atom, a methoxy, ethoxy or an acetoxy group, and n represents 0, 1 or 2.The process comprises reacting a compound of the formula (II): ##STR2## wherein R.sub.2 and n are as defined above, with an inorganic or organic nitrite, in an alcohol R.sub.1 OH, wherein R.sub.1 is as defined above, or in a mixture R.sub.1 OH-organic solvent in the presence of an inorganic or organic acid.The compounds of the formula (I) are known intermediates in the synthesis of human leucocyte elastase inhibitors (HLE).

Abstract: Compounds of the formula I ##STR1## wherein R' is a free or esterified carboxy group or a carboxylate anion and R.sup.2 is an organic group have beta-lactamase inhibition activity. A process for the preparation of the same and pharmaceutical compositions containing these compounds are provided.

Abstract: 6-substituted penem esters of formula (I): ##STR1## wherein R.sub.1 is halogen or a C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, phenyl, phenoxy, benzyl or sulphonyloxy group; R.sub.2 is a C.sub.1 -C.sub.4 alkyl, benzyl diphenylmethyl ##STR2## group where A is C.sub.1 -C.sub.4 alkyl, benzyl, p-nitrobenzyl or p-methoxybenzyl; and R.sub.3 is an organic radical, are elastase inhibitors and thereby useful antiinflammatory and antidegenerative agents.

Abstract: Compounds of formulae Ia and Ib ##STR1## wherein A is hydrogen atom or an organic residue, R.sup.1 is halogen atom, or an organic group, R.sup.2 is hydrogen or halogen atom, C.sub.1 -C.sub.4 alkyl or alkoxy group, R.sup.3 is hydrogen atom, C.sub.1 -C.sub.4 alkyl or alkoxy group, benzyl or a methylene group and R.sub.4 is an organic residue are disclosed. Compounds (Ia) and (Ib) are endowed with elastase inhibitory activity. A two-step process for their preparation starting from the corresponding 4-carboxy cephem or 3-carboxy penam is also provided.

Abstract: 6-substituted penem esters of formula (I): ##STR1## wherein R.sub.1 is halogen or a C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, phenyl, phenoxy, benzyl, or sulphonyloxy group; R.sub.2 is a C.sub.1 -C.sub.4 alkyl, benzyl diphenylmethyl ##STR2## group where A is C.sub.1 -C.sub.4 is C.sub.1 -C.sub.4 alkyl, benzyl, p-nitrobenzyl or p-methoxybenzyl; and R.sub.3 is an organic radical, are elastase inhibitors and thereby useful antiinflammatory and antidegenerative agents.

Abstract: A substantially (.gtoreq.95%) optically pure (5R,6S,1'R) penem of formula ##STR1## and the pharmaceutically acceptable salts and the ester prodrugs thereof, are endowed with antibacterial activity.

Abstract: There are provided compounds of formula I: ##STR1## wherein R.sup.1 is hydrogen or a C.sub.1 -C.sub.4 alkyl group either unsubstituted or substituted by one or more substituents chosen from a free or protected hydroxy or halogen atom;R.sup.2 is a free or esterified carboxy group or carboxylate anion;R.sup.3 and R.sup.4 are each independently hydrogen or organic group,X is --O--, ##STR2## --S--, Q is either(a") free or protected hydroxy, or(b") a C.sub.1 -C.sub.1 acyloxy, or(c") carbamoyloxy OCONH.sub.2, or(d") an optionally substituted heterocyclylthio group, or(e") an optionally substituted imido group, or(f") an optionally substituted quaternary ammonium group or(g") a halogen atom,A and the pharmaceutically or veterinarily acceptable salts thereof. There are provided also methods for preparing compounds of formula I. The compounds of formula I are useful as antibacterial agents.

Abstract: Compounds of formula ##STR1## wherein R is hydrogen atom or C.sub.1 -C.sub.4 alkyl group optionally substituted from halogen atom or hydroxy group optionally protected, A is a Z, Z--O--C--O-- or Z--C)-- residue, wherein Z is phenylene, naphthylene, heterocyclediyl, C.sub.1 -C.sub.7 alkylene, C.sub.2 -C.sub.4 alkenylene, alkynylene, ##STR2## C.sub.3 -C.sub.8 cycloalkylene, aralkylene radical optionally substituted, and O.sup.(+) represents a group +NR.sub.1 R.sub.2 R.sub.3, wherein R.sub.1, R.sub.2 and R.sub.3 are each either:(i) a optionally substituted alkyl, aralkyl or aryl radical or(ii) R.sub.1 is as defined above under (i) and R.sub.2 and R.sub.3, taken together, represent an optionally substituted or fused heterocyclic radical, or(iii) R.sub.1, R.sub.2 and R.sub.3, taken together, represent an optionally substituted azonia-bicyclo or tricyclo radical, or(iv) R.sub.1, R.sub.2 and R.sub.

Abstract: Compounds of the following formula I ##STR1## wherein X represents a sulphur or an oxygen atom,R is hydrogen or a C.sub.1 -C.sub.4 alkyl group either unsubstituted or substituted by one or more substituents chosen from a free or protected hydroxy group and halogen atom;A is a Z, Z--O--CO-- or --Z--CO-- residue, whereinZ represents(a) an optionally substituted phenylene or naphthylene group,(b) an optionally substituted heterocyclediyl radical wherein the hetero ring is mono or bicyclic, saturated or unsaturated containing at least one heteroatom selected from the group of oxygen, sulphur and nitrogen;(c) an optionally substituted linear or branched C.sub.1 -C.sub.7 alkylene radical;(d) a C.sub.2 -C.sub.4 alkenylene or alkynylene group or a group of formula ##STR2## (e) an optionally substituted C.sub.3 -C.sub.8 cycloalkylene ring; (f) an aralkylene radical of the formula ##STR3## wherein n is 1, 2 or 3; andQ.sup.(+) represents a +NR.sub.1 R.sub.2 R.sub.3 group, wherein(i) R.sub.1, R.sub.2, R.sub.

Abstract: Compounds of formula I ##STR1## wherein R.sub.1 and R.sub.2 is each H, halo or an organic group, R.sub.3 is H or organic group, n=1 or 2, M is a heavy mono- or divalent metal, or M.sub.2 A wherein M.sub.2 is a heavy divalent metal and A is an organic or inorganic group, are prepared by treating a starting penicillin in a solvent with a salt of M.sub.1 or M.sub.2 A in the presence of a base at a temperature of from -70.degree. to 100.degree. C.

Abstract: Antibacterial compounds of formula (I) ##STR1## wherein, R.sub.1 ' is alkyl or hydroxyalkyl;R.sub.2 is hydrogen or a carboxy protecting group; andY' is a group-S-heterocyclic or pyridyl, which group may be substituted, and pharmaceutically or veterinarily acceptable salts thereof and pharmaceutical compositions containing the same.

Abstract: There are provided compounds of formula ##STR1## wherein R is hydrogen atom or C.sub.1 -C.sub.3 alkyl group optionally substituted from halogen atom or hydroxy group optionally protected, and Q.sup.(+) represents a group ##STR2## wherein R.sub.1, R.sub.2 and R.sub.3 are each either: (i) optionally substituted alkyl, aralkyl or aryl radical or(ii) R.sub.1 is as defined above under (i) and R.sub.2, R.sub.3, taken together, represent an optionally substituted or fused heterocyclic radical or(iii) R.sub.1, R.sub.2, R.sub.3, taken together, represent an optionally substituted azonia-bicyclo or tricyclo radical or(iv) R.sub.1, R.sub.2, R.sub.3, taken together, represent an optionally substituted fused pyridinium radical or(v) R.sub.1, R.sub.2, R.sub.3, taken together, represent an optionally substituted pyrazimium, pyrazolium or pyridazinium radical, and the pharmaceutically or veterinarily acceptable salts thereof.A method of preparation is also provided.The compounds show high antibacterial activity.

Abstract: A new process is described for the preparation of (5R)-penem derivatives of the general formula I: ##STR1## wherein R.sub.1 represents a hydrogen atom or an organic group; R.sub.2 represents a hydrogen atom or a carboxy protecting group and Y represents a hydrogen or halogen atom or an organic group. A 2-thiacephem derivative of the general formula II: ##STR2## wherein R.sub.1, R.sub.2 and Y have the meanings/given above is oxidized by means of organic peracids to the corresponding sulphone of the general formula III: ##STR3## which is subsequently submitted to a desulphurative ring contraction by extrusion of SO.sub.2 to give exclusively the desired (5R)-penem derivatives of the general formula I.

Abstract: Penem derivatives are disclosed characterized by a substituted pyridiniomethyl group in the 2-position of the penem nucleus. The compounds of the present application exhibit better antibacterial activity than other known penem derivatives.

Abstract: A new process is described for the preparation of (5R)-penem derivatives of the general formula I: ##STR1## wherein R.sub.1 represents a hydrogen atom or an organic group; R.sub.2 represents a hydrogen atom or a carboxy protecting group and Y represents a hydrogen or halogen atom or an organic group. A 2-thiacephem derivative of the general formula II: ##STR2## wherein R.sub.1, R.sub.2 and Y have the meanings/given above is oxidized by means of organic peracids to the corresponding sulphone of the general formula III: ##STR3## which is subsequently submitted to a desulphurative ring contraction by extrusion of SO.sub.2 to give exclusively the desired (5R)-penem derivatives of the general formula I.

Abstract: A process for the preparation of compounds of formula (I) ##STR1## wherein R.sub.1 is hydrogen or an organic group;R.sub.2 is hydrogen or a carboxy protecting group; andY is a group-S-heterocyclic, acyloxy, alkoxy, alkylthio, pyridyl, which group may be substituted, or azido, and penem derivatives falling within the scope of formula (I) and pharmaceutically or veterinarily acceptable salts thereof.The process involves displacing a group L in the Y position with a reagent Y-H.

Abstract: Heteromonocyclic and heterobicyclic derivatives of unsaturated 7-ayclamide-3-cephem-4-carboxylic acid are disclosed, and process for preparing same. These compounds are suitable for treating infections caused by Gram-positive and Gram-negative microorganisms.

Abstract: Derivatives of N-substituted thiazolyl oxy-imino-substituted cephalosporins, such as, for instance, the compound 7.beta.-[2-(2-imino-3-hydroxy-4-thiazolinyl)-2-methoxy-imino-acetamino]-3- [(tetrazolo[1,5-b]pyridazin-6-yl)-thiomethyl]-3-cephem-4-carboxylic acid, are disclosed. The disclosed compounds have high anti-bacterial activity against Gram-positive and Gram-negative bacteria normally susceptible to cephalosporins.