flomoxef and its Impurities
Flomoxef is an oxacephem antibiotic. It has been used in trials studying the treatment of Urinary Tract Infection. Reference standards of Flomoxef API,and its pharmacopeial, non pharmacopeial impurities, and stable isotopes are listed below.


Sodium (7R)-7-(2-((difluoromethyl)thio)acetamido)-3-(hydroxymethyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Sodium (7R)-7-(2-((difluoromethyl)thio)acetamido)-3-(hydroxymethyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Catalogue No.:PA 06 79510
CAS :
NA
Molecular Formula : C12H13F2N2NaO7S
Molecular Weight : 390.29


Sodium (7S)-7-(2-((difluoromethyl)thio)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Sodium (7S)-7-(2-((difluoromethyl)thio)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Catalogue No.:PA 06 79520
CAS :
NA
Molecular Formula : C15H17F2N6NaO7S2
Molecular Weight : 518.45


2-((Difluoromethyl)thio)-N-((6R)-6-methoxy-1,7-dioxo-1,3,4,5a,6,7-hexahydroazeto[2,1-b]furo[3,4-d][1,3]oxazin-6-yl)acetamide
2-((Difluoromethyl)thio)-N-((6R)-6-methoxy-1,7-dioxo-1,3,4,5a,6,7-hexahydroazeto[2,1-b]furo[3,4-d][1,3]oxazin-6-yl)acetamide
Catalogue No.:PA 06 79530
CAS :
NA
Molecular Formula : C12H12F2N2O6S
Molecular Weight : 350.3


(6R,7R)-7-(2-((Difluoromethyl)thio)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxamide
(6R,7R)-7-(2-((Difluoromethyl)thio)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxamide
Catalogue No.:PA 06 79540
CAS :
NA
Molecular Formula : C15H19F2N7O6S2
Molecular Weight : 495.48


(6R,7R)-7-(2-((Difluoromethyl)thio)acetamido)-3-(hydroxymethyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
(6R,7R)-7-(2-((Difluoromethyl)thio)acetamido)-3-(hydroxymethyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
Catalogue No.:PA 06 79550
CAS :
2095697-76-8
Molecular Formula : C12H14F2N2O7S
Molecular Weight : 368.31


2-((Difluoromethyl)thio)-N-((5aR,6R)-6-methoxy-1,7-dioxo-1,4,5a,6-tetrahydro-3H,7H-azeto[2,1-b]furo[3,4-d][1,3]oxazin-6-yl)acetamide
2-((Difluoromethyl)thio)-N-((5aR,6R)-6-methoxy-1,7-dioxo-1,4,5a,6-tetrahydro-3H,7H-azeto[2,1-b]furo[3,4-d][1,3]oxazin-6-yl)acetamide
Catalogue No.:PA 06 79560
CAS :
2095485-03-1
Molecular Formula : C12H12F2N2O6S
Molecular Weight : 350.29


Benzhydryl (6R,7R)-3-(chloromethyl)-7-((1-(((Z)-2-chlorovinyl)oxy)-2-((difluoromethyl)thio)ethyl)amino)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Benzhydryl (6R,7R)-3-(chloromethyl)-7-((1-(((Z)-2-chlorovinyl)oxy)-2-((difluoromethyl)thio)ethyl)amino)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Catalogue No.:PA 06 79570
CAS :
NA
Molecular Formula : C27H26Cl2F2N2O6S
Molecular Weight : 615.47


2-((Difluoromethyl)thio)-N-(5-(3,4-dihydroxy-2,5-dihydro-1H-pyrrol-1-yl)-4-(oxetan-3-ylidene)-3-oxo-2,6-dioxabicyclo[3.1.1]hept-1(7)-en-7-yl)acetamide
2-((Difluoromethyl)thio)-N-(5-(3,4-dihydroxy-2,5-dihydro-1H-pyrrol-1-yl)-4-(oxetan-3-ylidene)-3-oxo-2,6-dioxabicyclo[3.1.1]hept-1(7)-en-7-yl)acetamide
Catalogue No.:PA 06 79590
CAS :
NA
Molecular Formula : C15H14F2N2O7S
Molecular Weight : 404.34


Benzhydryl (6R,7S)-3-(chloromethyl)-7-(4-methylbenzamido)-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Benzhydryl (6R,7S)-3-(chloromethyl)-7-(4-methylbenzamido)-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Catalogue No.:PA 06 79630
CAS :
1825345-61-6
Molecular Formula : C29H25ClN2O5
Molecular Weight : 516.98


Benzhydryl (6R,7R)-3-(chloromethyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Benzhydryl (6R,7R)-3-(chloromethyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Catalogue No.:PA 06 79660
CAS :
134237-56-2
Molecular Formula : C25H23ClF2N2O6S
Molecular Weight : 552.97


(R)-2-(2-((Difluoromethyl)thio)acetamido)-2-methoxy-2-((R)-7-oxo-1,2,5,7-tetrahydro-4H-furo[3,4-d][1,3]oxazin-2-yl)acetic Acid
(R)-2-(2-((Difluoromethyl)thio)acetamido)-2-methoxy-2-((R)-7-oxo-1,2,5,7-tetrahydro-4H-furo[3,4-d][1,3]oxazin-2-yl)acetic Acid
Catalogue No.:PA 06 0791000
CAS :
NA
Molecular Formula : C12H14F2N2O7S
Molecular Weight : 368.31


(R)-2-((R)-Carboxy(2-((difluoromethyl)thio)acetamido)(methoxy)methyl)-5-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-3,6-dihydro-2H-1,3-oxazine-4-carboxylic Acid
(R)-2-((R)-Carboxy(2-((difluoromethyl)thio)acetamido)(methoxy)methyl)-5-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-3,6-dihydro-2H-1,3-oxazine-4-carboxylic Acid
Catalogue No.:PA 06 0791001
CAS :
2095697-75-7
Molecular Formula : C15H20F2N6O8S2
Molecular Weight : 514.48


(6S,7S)-7-((S)-2-(2-((Difluoromethyl)thio)acetamido)-N-(2-((difluoromethyl)thio)acetyl)-2-methoxy-2-((S)-7-oxo-1,2,5,7-tetrahydro-4H-furo[3,4-d][1,3]oxazin-2-yl)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
(6S,7S)-7-((S)-2-(2-((Difluoromethyl)thio)acetamido)-N-(2-((difluoromethyl)thio)acetyl)-2-methoxy-2-((S)-7-oxo-1,2,5,7-tetrahydro-4H-furo[3,4-d][1,3]oxazin-2-yl)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
Catalogue No.:PA 06 0791002
CAS :
2095482-92-9
Molecular Formula : C27H30F4N8O13S3
Molecular Weight : 846.75


(6R,7R)-3-(((1-(2-((R)-2-((R)-4-Carboxy-5-methylene-5,6-dihydro-2H-1,3-oxazin-2-yl)-2-(2-((difluoromethyl)thio)acetamido)-2-methoxyacetoxy)ethyl)-1H-tetrazol-5-yl)thio)methyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
(6R,7R)-3-(((1-(2-((R)-2-((R)-4-Carboxy-5-methylene-5,6-dihydro-2H-1,3-oxazin-2-yl)-2-(2-((difluoromethyl)thio)acetamido)-2-methoxyacetoxy)ethyl)-1H-tetrazol-5-yl)thio)methyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
Catalogue No.:PA 06 0791003
CAS :
NA
Molecular Formula : C27H30F4N8O13S3
Molecular Weight : 846.75


(6R,7R)-3-(((1-(2-((R)-2-((2R,5R)-4-Carboxy-5-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-5,6-dihydro-2H-1,3-oxazin-2-yl)-2-(2-((difluoromethyl)thio)acetamido)-2-methoxyacetoxy)ethyl)-1H-tetrazol-5-yl)thio)methyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
(6R,7R)-3-(((1-(2-((R)-2-((2R,5R)-4-Carboxy-5-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-5,6-dihydro-2H-1,3-oxazin-2-yl)-2-(2-((difluoromethyl)thio)acetamido)-2-methoxyacetoxy)ethyl)-1H-tetrazol-5-yl)thio)methyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
Catalogue No.:PA 06 0791004
CAS :
NA
Molecular Formula : C30H36F4N12O14S4
Molecular Weight : 992.92


(6R,7R)-3-(((1-(2-((R)-2-((2R,5S)-4-Carboxy-5-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-5,6-dihydro-2H-1,3-oxazin-2-yl)-2-(2-((difluoromethyl)thio)acetamido)-2-methoxyacetoxy)ethyl)-1H-tetrazol-5-yl)thio)methyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
(6R,7R)-3-(((1-(2-((R)-2-((2R,5S)-4-Carboxy-5-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-5,6-dihydro-2H-1,3-oxazin-2-yl)-2-(2-((difluoromethyl)thio)acetamido)-2-methoxyacetoxy)ethyl)-1H-tetrazol-5-yl)thio)methyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
Catalogue No.:PA 06 0791005
CAS :
NA
Molecular Formula : C30H36F4N12O14S4
Molecular Weight : 992.92


Sodium 4-hydroxy-3-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-2-oxobutanoate
Sodium 4-hydroxy-3-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-2-oxobutanoate
Catalogue No.:PA 06 0791006
CAS :
NA
Molecular Formula : C8H11N4NaO5S
Molecular Weight : 298.25


Methyl (R)-3-((difluoromethoxy)methyl)-7-imino-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Methyl (R)-3-((difluoromethoxy)methyl)-7-imino-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Catalogue No.:PA 06 0791007
CAS :
2095489-25-9
Molecular Formula : C10H10F2N2O5
Molecular Weight : 276.2


(6S,7S)-7-((S)-2-(2-((Difluoromethyl)thio)acetamido)-N-(2-((difluoromethyl)thio)acetyl)-2-methoxy-2-((S)-7-oxo-1,2,5,7-tetrahydro-4H-furo[3,4-d][1,3]oxazin-2-yl)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-3-ene-2-carboxylic Acid
(6S,7S)-7-((S)-2-(2-((Difluoromethyl)thio)acetamido)-N-(2-((difluoromethyl)thio)acetyl)-2-methoxy-2-((S)-7-oxo-1,2,5,7-tetrahydro-4H-furo[3,4-d][1,3]oxazin-2-yl)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-3-ene-2-carboxylic Acid
Catalogue No.:PA 06 0791008
CAS :
2095697-71-3
Molecular Formula : C27H30F4N8O13S3
Molecular Weight : 846.75


(6R)-3-(((1-(2-((S)-2-((S)-4-Carboxy-5-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-3,6-dihydro-2H-1,3-oxazin-2-yl)-2-(2-((difluoromethyl)thio)acetamido)-2-methoxyacetoxy)ethyl)-1H-tetrazol-5-yl)thio)methyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
(6R)-3-(((1-(2-((S)-2-((S)-4-Carboxy-5-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-3,6-dihydro-2H-1,3-oxazin-2-yl)-2-(2-((difluoromethyl)thio)acetamido)-2-methoxyacetoxy)ethyl)-1H-tetrazol-5-yl)thio)methyl)-7-(2-((difluoromethyl)thio)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
Catalogue No.:PA 06 0791009
CAS :
NA
Molecular Formula : C30H36F4N12O14S4
Molecular Weight : 992.92


(6S,7S)-3-(Chloromethyl)-7-((S)-2-(2-((difluoromethyl)thio)acetamido)-N-(2-((difluoromethyl)thio)acetyl)-2-methoxy-2-((S)-7-oxo-1,2,5,7-tetrahydro-4H-furo[3,4-d][1,3]oxazin-2-yl)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxamide
(6S,7S)-3-(Chloromethyl)-7-((S)-2-(2-((difluoromethyl)thio)acetamido)-N-(2-((difluoromethyl)thio)acetyl)-2-methoxy-2-((S)-7-oxo-1,2,5,7-tetrahydro-4H-furo[3,4-d][1,3]oxazin-2-yl)acetamido)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxamide
Catalogue No.:PA 06 0791010
CAS :
2095697-74-6
Molecular Formula : C24H26ClF4N5O11S2
Molecular Weight : 736.06


(R)-2-(2-((Difluoromethyl)thio)acetamido)-2-((R)-4-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)carbonyl)-5-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-3,6-dihydro-2H-1,3-oxazin-2-yl)-2-methoxyacetic Acid
(R)-2-(2-((Difluoromethyl)thio)acetamido)-2-((R)-4-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)carbonyl)-5-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-3,6-dihydro-2H-1,3-oxazin-2-yl)-2-methoxyacetic Acid
Catalogue No.:PA 06 0791011
CAS :
2095489-28-2
Molecular Formula : C18H24F2N10O8S3
Molecular Weight : 642.63


(6R,7R)-7-(2-((Difluoromethyl)thio)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-3-ene-2-carboxylic Acid
(6R,7R)-7-(2-((Difluoromethyl)thio)acetamido)-3-(((1-(2-hydroxyethyl)-1H-tetrazol-5-yl)thio)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-3-ene-2-carboxylic Acid
Catalogue No.:PA 06 0791012
CAS :
2095697-77-9
Molecular Formula : C15H18F2N6O7S2
Molecular Weight : 496.46


2-((Difluoromethyl)thio)-N-((6R,7R)-3-(hydroxymethyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-en-7-yl)acetamide
2-((Difluoromethyl)thio)-N-((6R,7R)-3-(hydroxymethyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-en-7-yl)acetamide
Catalogue No.:PA 06 0791013
CAS :
2095485-77-9
Molecular Formula : C11H14F2N2O5S
Molecular Weight : 324.3


(6R,7R)-7-(2-((Difluoromethyl)thio)acetamido)-3-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
(6R,7R)-7-(2-((Difluoromethyl)thio)acetamido)-3-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid
Catalogue No.:PA 06 0791015
CAS :
NA
Molecular Formula : C15H18F2N6O7S2
Molecular Weight : 496.46


Sodium (7R)-7-(2-((difluoromethyl)thio)acetamido)-3-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Sodium (7R)-7-(2-((difluoromethyl)thio)acetamido)-3-((4-(2-hydroxyethyl)-5-thioxo-4,5-dihydro-1H-tetrazol-1-yl)methyl)-7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate
Catalogue No.:PA 06 0791016
CAS :
NA
Molecular Formula : C15H17F2N6NaO7S2
Molecular Weight : 518.44