Abstract: There is provided an improved process for producing novel compounds represented by the general formula: ##STR1## wherein the ring A/ represents a pyrrole ring which may be hydrogenated; X represents an amino, hydroxyl or mercapto group; R.sup.1, R.sup.2 and R.sup.3 each, being the same as or different from the other, represents hydrogen or an alkyl, alkenyl or alkynyl group which may be substituted; R.sup.4 represents OR.sup.5 wherein R.sup.5 represents hydrogen or a hydrocarbon group which may be substituted or NHCH(COOR.sup.6)CH.sub.2 CH.sub.2 COOR.sup.7 wherein R.sup.6 and R.sup.7 each represents hydrogen or a hydrocarbon group which may be substituted; and n represents an integer of 1 to 4, or a salt thereof from compounds represented by the general formula: ##STR2## wherein X, R.sup.1, R.sup.2, R.sup.3, R.sup.4 and n are the same as defined above; Y.sup.1 and Y.sup.2 each represents oxygen or sulfur atom; R.sup.8 and R.sup.

Abstract: A compound of the formula (I): ##STR1## wherein the ring A is a pyrrole ring which may be hydrogenated, X is an amino group, a hydroxyl group or a mercapto group, Y is a hydrogen atom or a hydroxyl group, --COOR.sup.1 and --COOR.sup.2 may be the same or different and are a carboxyl group which may be esterified, --B-- is a divalent heterocyclic group or a lower alkylene group each of which may be substituted, and Z is a straight C.sub.2-4 divalent group which may be substituted, or its salt, a method for the production of the same and an antitumor agent containing the same.

Abstract: There is provided an improved process for producing novel compounds represented by the general formula: ##STR1## wherein the ring A represents a pyrrole ring which may be hydrogenated; X represents an amino, hydroxyl or mercapto group; R.sup.1, R.sup.2 and R.sup.3 each being the same as or different from the other, represents hydrogen or an alkyl, alkenyl or alkynyl group which may be substituted; R.sup.4 represents OR.sup.5 wherein R.sup.5 represents hydrogen or a hydrocarbon group which may be substituted or NHCH(COOR.sup.6)CH.sub.2 CH.sub.2 COOR.sup.7 wherein R.sup.6 and R.sup.7 each represents hydrogen or a hydrocarbon group which may be substituted; and n represents an integer of 1 to 4, or a salt thereof from compounds represented by the general formula: ##STR2## wherein X, R.sup.1, R.sup.2, R.sup.3, R.sup.4 and n are the same as defined above; Y.sup.1 and Y.sup.2 each represents oxygen or sulfur atom; R.sup.8 and R.sup.

Abstract: A compound of the formula ##STR1## wherein the ring A pyrrole or pyrroline ring, X is an amino group or a hydroxyl group, Y is a hydrogen atom, an amino group or a hydroxyl group, R is a hydrogen atom, a fluorine atom, an alkyl group, an alkenyl group or an alkynyl group, --COOR.sup.1 and --COOR.sup.2 are independently carboxyl groups which may be esterified and n is an integer of 2 to 4, and R may be different in each of the n repeating units, and salts thereof have excellent antitumor effects, and can be used as antitumor agents in mammals.

Abstract: A compound of the formula ##STR1## wherein the ring A is a pyrrole or pyrroline ring, X is an amino group or a hydroxyl group, Y is a hydrogen atom, an amino group or a hydroxyl group, R is a hydrogen atom, a fluorine atom, an alkyl group, an alkenyl group or an alkynyl group, --COOR.sup.1 and --COOR.sup.2 are independently carboxyl groups which may be esterified and n is an integer of 2 to 4, and R may be different in each of the n repeating units, and salts thereof have excellent antitumor effects, and can be used as antitumor agents in mammals.

Abstract: A compound of the formula ##STR1## wherein the ring .circle.A is a pyrrole or pyrroline ring, X is an amino group or a hydroxyl group, Y is a hydrogen atom, an amino group or a hydroxyl group, R is a hydrogen atom, a fluorine atom, an alkyl group, an alkenyl group or an alkynyl group, --COOR.sup.1 and --COOR.sup.2 are independently carboxyl groups which may be esterified and n is an integer of 2 to 4, and R may be different in each of the n repeating units, and salts thereof have excellent antitumor effects, and can be used as antitumor agents in mammals.

Abstract: Novel cephalosporins shown by the general formula: ##STR1## wherein Y is an acyloxy group, a quaternary ammonium group or a group of the formula: --S--R in which R is a nitrogen-containing heterocyclic group, and pharmaceutically acceptable salts thereof have high antibacterial properties against Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa and Serratia marcescens.