Abstract: Antibacterial penems of formula (I), where R represents a hydrogen atom or a hydroxy protecting group, are prepared by reacting a .beta.-lactam of formula (II) with an oxalyl halide in an inert solvent in the presence of an organic or inorganic base or an acid scavenger to produce a compound of formula (III), wherein X is a halogen atom, treating the resultant compound of formula (III) with a 1,3-dioxolen-2-one of formula (IV), wherein Y is a hydroxy group, in the presence of molecular sieves or an organic or inorganic base to produce a compound of formula (V), and cyclizing the compound of formula (V) in the presence of a trialkylphosphite to provide the penems of formula (I).

Abstract: The present invention relates to the use as antivirals of compounds of formula: ##STR1## wherein B is a purinic or pyrimidinic heterocycle; X is oxygen or sulphur; R.sup.1 is a hydroxyl group or a hydrogen atom; R.sup.2 is a linear, branched or cyclic, alkyl group of up to twenty carbon atoms; R.sup.3 is as specified for R.sup.2 above or a hydrogen atom, a cation or a polyhydroxy group.

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: 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: A method is provided for treating a warm-blooded animal having a susceptible bacterial infection which comprises administering orally to said animal a non-toxic, antibacterially effective amount of acetoxymethyl ester of (5R,6S)-2(5R,6S)-2-carbamoyloxymethyl-6-[1(R)-hydroxyethyl]-2-penem-3-carb oxylic acid.

Abstract: Orally administrable pharmaceutical compositions comprising 3-(N-piperidinomethyl-azino)methylrifamycin S as the active substance are disclosed. The active substance is easily soluble in water even at low pH values and is provided with good bioavailability. Such compositions are useful in the treatment of bacterial infections.

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: 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: A process for preparing 2-methyl substituted penems useful as antibiotics agent and/or as intermediates thereof, by reacting an appropriate 1-imido-3,4-disubstituted azetidinone derivative with a trivalent organophosphorus compound in an inert solvent at a temperature of from 110.degree. to 150.degree. C. for a period of from 2 hours to a few days.

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: There are disclosed .beta.-lactam-containing compounds of the formula: ##STR1## where R is hydrogen, lower alkyl, trichloroethyl, acetonyl, benzyl, substituted benzyl, phenyl, substituted phenyl, benzidryl or a residue that will undergo metabolic activation "in vivo" and have favorable pharmacokinetic properties; R.sup.1 is a hydrogen atom, lower alkyl, lower alkoxy, cycloalkyl, or hydroxyalkyl, with the alcoholic function of the hydroxyalkyl being free or protected; Z is hydrogen, halogen, hydroxy, amino, carbamoyloxy, mercapto, pyridinium, OR.sup.2, OCOR.sup.2, NHCOR.sup.2, or SR.sup.3 wherein each of R.sup.2 and R.sup.3 is any of lower alkyl, aryl, or a heterocyclic ring, each of which may be substituted or unsubstituted, and n is 0 or 1. The compounds have broad spectrum antibacterial activity and .beta.-lactamase inhibiting activity. Processes for the production of the .beta.-lactam-containing compounds and various intermediates in the production of those compounds are also disclosed.

Abstract: Processes for the preparation of a penem derivative of formula I ##STR1## wherein n=0 or 1; R is a carboxy protecting group or H;R.sub.1 is hydrogen, a hydrocarbon group substituted or unsubstituted, or lower alkoxy; andR.sub.2 is hydrogen, C.sub.1 -C.sub.5 alkyl, carbamoyl N-substituted by lower alkyl or unsubstituted, or an acyl group;and the pharmaceutically acceptable salts thereof.These processes allow one to prepare stereospecifically only 5R derivatives, and are characterized by R.sub.2 -introduction at a very late stage in the synthesis, thereby enabling a great number of compounds of formula I to be prepared.Penem derivatives are useful antibacterial agents.

Abstract: Azinomethyl-rifamycins I ##STR1## (wherein Y=H or COCH.sub.3 and either R.sub.1 =C.sub.1 -C.sub.7 alkyl or C.sub.3 -C.sub.4 alkenyl and R.sub.2 =C.sub.1 -C.sub.7 alkyl, C.sub.2 -C.sub.4 cloro-, hydroxy-, or alkoxy-alkyl C.sub.3 -C.sub.4 alkenyl, cycloalkyl having a C.sub.3 -C.sub.7 ring, cycloalkylalkyl having a C.sub.3 -C.sub.6 ring, phenyl or C.sub.7 -C.sub.8 aralkyl optionally monohalogen substituted in the aryl group or NR.sub.1 R.sub.2 = a cyclic moiety, said moiety being pyrrolidinyl, piperidinyl, hexahydroazepinyl or heptahydroazocinyl, each of which are unsubstituted or substituted with 1 or 2 methyl radicals, 4-alkyl-1-piperazinyl, morpholinyl or 1,2,3,4-tetrahydroisoquinolinyl) are prepared from rifamycin S by(a) dissolving the rifamycin S in tetrahydrofuran, CHCl.sub.3, dioxan, CH.sub.2 Cl.sub.2 or dichloroethane(b) adding (i) a Schiff's base CH.sub.2 =NR.sub.3 wherein R.sub.3 = t-alkyl or (ii) a compound R.sub.4 N(CH.sub.2 OR.sub.5).sub.2 wherein R.sub.

Abstract: There are disclosed .beta.-lactam-containing compounds of the formula: ##STR1## where R is hydrogen, lower alkyl, trichloroethyl, acetonyl, benzyl, substituted benzyl, phenyl, substituted phenyl, benzidryl or a residue that will undergo metabolic activation "in vivo" and have favorable pharmacokinetic properties; R.sup.1 is a hydrogen atom, lower alkyl, lower alkoxy, cycloalkyl, or hydroxyalkyl, with the alcoholic function of the hydroxyalkyl being free or protected; Z is hydrogen, halogen, hydroxy, amino, carbamoyloxy, mercapto, pyridinium, OR.sup.2, OCOR.sup.2, NHCOR.sup.2, or SR.sup.3 wherein each of R.sup.2 and R.sup.3 is any of lower alkyl, aryl, or a heterocyclic ring, each of which may be substituted or unsubstituted, and n is 0 or 1. The compounds have broad spectrum antibacterial activity and .beta.-lactamase inhibiting activity. Processes for the production of the .beta.-lactam-containing compounds and various intermediates in the production of those compounds are also disclosed.