List of carboxylic acids

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Carboxylic acids are organic acids characterized by a carboxyl (-COOH) functional group. The naming of these compounds is governed by IUPAC nomenclature, which ensures systematic and consistent naming of chemicals. Numerous organic compounds have other common names, often originating in historical source material thereof. The systematic IUPAC name is not always the preferred IUPAC name, for example, lactic acid is a common, and also the preferred, name for what systematic rules call 2-hydroxypropanoic acid.

Contents

This list is ordered by the number of carbon atoms in a carboxylic acid.

C1

Common nameIUPAC nameStructural formulaNotes
formic acid methanoic acidHCO2H
carbonic acid hydroxymethanoic acidHOCO2HDespite having an organic-like name, H2CO3 is not considered an organic compound.

C2

Common nameIUPAC nameStructural formula
Acetic acid ethanoic acidCH3CO2H
Glycolic acid hydroxyacetic acidHOCH2CO2H
Glyoxylic acid oxoacetic acidOHCCO2H
Oxalic acid ethanedioic acidHO2CCO2H

C3

IUPAC nameCommon nameStructural formula
Propionic acid propanoic acid
ethanecarboxylic acid
CH3CH2CO2H
Acrylic acid propenoic acid
acroleic acid
ethylenecarboxylic acid
vinylformic acid
CH2=CHCO2H
Propiolic acid propynoic acid
propargylic acid
acetylene carboxylic acid
CH≡CCO2H
Lactic acid 2-hydroxypropanoic acid
milk acid
CH3CHOHCO2H
3-Hydroxypropionic acid 3-hydroxypropanoic acid
hydracrylic acid
CH2OHCH2CO2H
Glyceric acid 2,3-dihydroxypropanoic acidCH2OHCHOHCO2H
Pyruvic acid 2-oxopropanoic acid
α-ketopropionic acid
acetylformic acid
pyroracemic acid
CH3COCO2H
3-oxopropanoic acid malonic semialdehyde
3-oxopropionic acid
OHCCH2CO2H
2,3-dioxopropanoic acid mesoxalic semialdehyde
dioxopropionic acid
OHCCOCO2H
Malonic acid propanedioic acid
methanedicarboxylic acid
HO2CCH2CO2H
Tartronic acid 2--hydroxypropanedioic acid
hydroxymalonic acid
HO2CCHOHCO2H
2,2-dihydroxypropanedioic acid dihydroxymalonic acid
mesoxalic acid monohydrate
HO2CC(OH)2CO2H
Mesoxalic acid oxopropanedioic acid
ketomalonic acid
oxomalonic acid
HO2CCOCO2H
Glycidic acid 2-oxiranecarboxylic acid
oxirane-2-carboxylic acid
CH2OCHCO2H

C4

IUPAC nameCommon nameStructural formula
butanoic acid butyric acid
propanecarboxylic acid
CH3(CH2)2COOH
2-methylpropanoic acid isobutyric acid
isobutanoic acid
(CH3)2CHCOOH
(E)-but-2-enoic acid crotonic acid
trans-butenoic acid
3-methylacrylic acid
β-methacrylic acid
(E)-2-butenoic acid
CH3CH=CHCOOH
(Z)-but-2-enoic acid isocrotonic acid
cis-crotonic acid
cis-butenoic acid
(Z)-2-butenoic acid
CH3CH=CHCOOH
2-methylpropenoic acid methacrylic acid
α-methacrylic acid
2-methylacrylic acid
isobutenoic acid
CH2=C(CH3)COOH
but-3-enoic acid vinylacetic acid
allylic acid
3-butenoic acid
β-butenoic acid
CH2=CHCH2COOH
but-2-ynoic acid tetrolic acid
2-butynoic acid
CH3C≡CCOOH
2-hydroxybutanoic acid 2-hydroxybutyric acid
α-hydroxybutyrate
CH3CH2CHOHCOOH
3-hydroxybutanoic acid β-hydroxybutyric acid
3-hydroxybutyric acid
CH3CHOHCH2COOH
4-hydroxybutanoic acid γ-hydroxybutyric acid
GHB
4-hydroxybutyric acid
HOCH2(CH2)2COOH
2-oxobutanoic acid α-ketobutyric acidCH3CH2COCOOH
3-oxobutanoic acid acetoacetic acid
diacetic acid
CH3COCH2COOH
4-oxobutanoic acid succinic semialdehydeOHC(CH2)2COOH
butanedioic acid succinic acidHOOC(CH2)2COOH
2-methylpropanedioic acid methylmalonic acidHOOCCH(CH3)COOH
(E)-butenedioic acid fumaric acid
trans-1,2-ethylenedicarboxylic acid
trans-butenedioic acid
allomaleic acid
boletic acid
donitic acid
lichenic acid
HOOCCH=CHCOOH
(Z)-butenedioic acid maleic acid
cis-butenedioic acid
malenic acid
maleinic acid
toxilic acid
HOOCCH=CHCOOH
butynedioic acid acetylenedicarboxylic acid
2-butynedioic acid
HOOCC≡CCOOH
hydroxybutanedioic acid malic acid
hydroxysuccinic acid
2-hydroxybutanedioic acid
HOOCCH2CHOHCOOH
2,3-dihydroxybutanedioic acid tartaric acid
2,3-dihydroxysuccinic acid
racemic acid
threaric acid
uvic acid
paratartaric acid
HOOC(CHOH)2COOH
oxobutanedioic acid oxaloacetic acid
oxalacetic acid
oxosuccinic acid
ketosuccinic acid
HOOCCH2COCOOH
dioxobutanedioic acid dioxosuccinic acidHOOC(CO)2COOH

C5

IUPAC nameCommon nameStructural formula
pentanoic acid valeric acid
valerianic acid
butane-1-carboxylic acid
CH3(CH2)3COOH
3-methylbutanoic acid isovaleric acid
isopentanoic acid
delphinic acid
β-methylbutiric acid
3-methylbutiric acid
(CH3)2CHCH2COOH
2-methylbutanoic acid 2-methylbutiric acidCH3CH2CH(CH3)COOH
2,2-dimethylpropanoic acid pivalic acid
trimethylacetic acid
neopentanoic acid
(CH3)3CCOOH
3-hydroxypentanoic acid β-hydroxyvaleric acid
3-hydroxyvaleric acid
β-hydroxypentanoate
CH3CH2CHOHCH2COOH
4-hydroxypentanoic acid γ-hydroxyvaleric acid
GHV
4-methyl-GHB
CH3CHOH(CH2)2COOH
3-hydroxy-3-methylbutanoic acid β-hydroxy β-methylbutyric acid
HMB
β-hydroxyisovaleric acid
3-hydroxyisovaleric acid
(CH3)2COHCH2COOH
pentanedioic acid glutaric acid
propane-1,3-dicarboxylic acid
n-pyrotartaric acid
HOOC(CH2)3COOH
2-oxopentanedioic acid α-ketoglutaric acid
2-ketoglutaric acid
2-oxoglutaric acid
oxoglutaric acid
HOOC(CH2)2COCOOH
3-oxopentanedioic acid acetonedicarboxylic acid
3-oxoglutaric acid
β-ketoglutaric acid
3-ketoglutaric acid
HOOCCH2COCH2COOH
furan-2-carboxylic acid 2-furoic acid
α-furoic acid
pyromucic acid
2-carboxyfuran
α-furancarboxylic acid
furyl-COOH
tetrahydrofuran-2-carboxylic acid tetrahydro-2-furoic acid
tetrahydrofuroic acid
tetrahydrofuran-2-carboxylic acid
tetrahydrofuryl-COOH

C6

IUPAC nameCommon nameStructural formula
hexanoic acid caproic acid
n-caproic acid
CH3(CH2)4COOH
hexanedioic acid adipic acid
hexane-1,6-dioic acid
HOOC(CH2)4COOH
2,3-dimethylbutanoic acidCH3(CHCH3)2COOH
3,3-dimethylbutanoic acidCH3C(CH3)2CH2COOH
2-hydroxypropane-1,2,3-tricarboxylic acid citric acid
3-carboxy-3-hydroxypentanedioic acid
2-hydroxy-1,2,3-propanetricarboxylic acid
HOC(COOH)((CH2)COOH)2
prop-1-ene-1,2,3-tricarboxylic acid aconitic acid
achilleic acid
equisetic acid
citridinic acid
pyrocitric acid
HOOCCH=C(COOH)CH2COOH
1-hydroxypropane-1,2,3-tricarboxylic acid isocitric acidHOOCCHOHCH(COOH)CH2COOH
(2E,4E)-hexa-2,4-dienoic acid sorbic acidCH3(CH=CH)2COOH

C7

IUPAC nameCommon nameStructural formula
heptanoic acid enanthic acid
oenanthic acid
n-Heptylic acid
n-Heptoic acid
CH3(CH2)5COOH
heptanedioic acid pimelic acid HOOC(CH2)5COOH
cyclohexanecarboxylic acid C
6
H
11
COOH
benzenecarboxylic acid benzoic acid
carboxybenzene
dracylic acid
C
6
H
5
COOH
2-hydroxybenzoic acid salicylic acid HOC
6
H
4
COOH
2,2-dimethylpentanoic acidCH3(CH2)2C(CH3)2COOH
2,3-dimethylpentanoic acidC2H5(CHCH3)2COOH
2,4-dimethylpentanoic acidCH3(CHCH3)CH2(CHCH3)COOH
3,3-dimethylpentanoic acidC2H5C(CH3)2CH2COOH
2-ethylpentanoic acidC3H7CH(C2H5)COOH
3-ethylpentanoic acidC2H5CH(C2H5)CH2COOH
2-methylhexanoic acidC4H9CH(CH3)COOH
3-methylhexanoic acidC3H7CH(CH3)CH2COOH
2,2,3-trimethylbutanoic acidCH3CH(CH3)C(CH3)2COOH
2-ethyl-2-methylbutanoic acidC2H5C(C2H5)(CH3)COOH
2-ethyl-3-

methylbutanoic acid

CH3CH(CH3)CH(C2H5)COOH

C8

IUPAC nameCommon nameStructural formula
octanoic acid caprylic acidCH3(CH2)6COOH
benzene-1,2-dicarboxylic acid phthalic acidC6H4(COOH)2
benzene-1,3-dicarboxylic acid isophthalic acidC6H4(COOH)2
benzene-1,4-dicarboxylic acid terephthalic acidC6H4(COOH)2
2-methylheptanoic acidC5H11CH(CH3)COOH
3-methylheptanoic acidC4H9CH(CH3)CH2COOH
4-methylheptanoic acidC3H7CH(CH3)C2H4COOH
5-methylheptanoic acidC2H5CH(CH3)C3H6COOH
6-methylheptanoic acid(CH3)2CHC4H8COOH
2,2-dimethylhexanoic acidC4H9C(CH3)2COOH
2,3-dimethylhexanoic acidC3H7[CH(CH3)]2COOH
2,4-dimethylhexanoic acidC2H5CH(CH3)CH2CH(CH3)COOH
2,5-dimethylhexanoic acidCH3CH(CH3)C2H4(CH3)COOH
3,3-dimethylhexanoic acidC3H7C(CH3)2CH2COOH
3,4-dimethylhexanoic acidC2H5[CH(CH3)]2CH2COOH
3,5-dimethylhexanoic acid(CH3)2CHCH2CH(CH3)CH2COOH
4,4-dimethylhexanoic acidC2H5C(CH3)2C2H4COOH
4,5-dimethylhexanoic acidCH3[CH(CH)3]2C2H4COOH
5,5-dimethylhexanoic acid(CH3)3CC3H6COOH
2-ethanehexanoic acidC4H9CH(C2H5)COOH
3-ethanehexanoic acidC3H7CH(C2H5)CH2COOH
4-ethanehexanoic acidC2H5CH(C2H5)C2H4COOH
5-ethanehexanoic acidCH3CH(C2H5)C3H6COOH
2-octenoic acidC5H11CH=CHCOOH
3-octenoic acidC4H9CH=CHCH2COOH
4-octenoic acidC3H7CH=CHC2H4COOH
5-octenoic acidC2H5CH=CHC3H6COOH
6-octenoic acidCH3CH=CHC4H8COOH
7-octenoic acidCH2=CHC5H10COOH

2-6 dimethyl octen dioic acid

C9

IUPAC nameCommon nameStructural formula
nonanoic acid pelargonic acid
1-octanecarboxylic acid
CH3(CH2)7COOH
benzene-1,3,5-tricarboxylic acid trimesic acid C
6
H
3
(COOH)
3
(E)-3-phenylprop-2-enoic acid cinnamic acid
trans-cinnamic acid
phenylacrylic acid
cinnamylic acid
3-phenylacrylic acid
(E)-cinnamic acid
benzenepropenoic acid
isocinnamic acid
C
6
H
5
CH=CHCOOH

C10

IUPAC nameCommon nameStructural formula
decanoic acid capric acid
CH3(CH2)8COOH
decanedioic acid sebacic acid
1,8-octanedicarboxylic acid
HOOC(CH2)8COOH

C11

IUPAC nameCommon nameStructural formula
undecanoic acid hendecanoic acidCH3(CH2)9COOH

C12

IUPAC nameCommon nameStructural formula
dodecanoic acid lauric acid
dodecylic acid
dodecoic acid
laurostearic acid
fulvic acid
1-undecanecarboxylic acid
duodecylic acid
CH3(CH2)10COOH
benzene-1,2,3,4,5,6-hexacarboxylic acid mellitic acid
graphitic acid
benzenehexacarboxylic acid
C
6
(COOH)
6

C13

IUPAC nameCommon nameStructural formula
tridecanoic acid tridecylic acidCH3(CH2)11COOH

C14

IUPAC nameCommon nameStructural formula
tetradecanoic acid myristic acidCH3(CH2)12COOH

C15

IUPAC nameCommon nameStructural formula
pentadecanoic acid pentadecylic acidCH3(CH2)13COOH

C16

IUPAC nameCommon nameStructural formula
hexadecanoic acid palmitic acidCH3(CH2)14COOH

C17

IUPAC nameCommon nameStructural formula
heptadecanoic acid margaric acid
heptadecylic acid
CH3(CH2)15COOH

C18

IUPAC nameCommon nameStructural formula
octadecanoic acid stearic acidCH3(CH2)16COOH
(9Z)-octadec-9-enoic acid oleic acid
(9Z)-octadecenoic acid
(Z)-octadec-9-enoic acid
cis-9-octadecenoic acid
cis9-octadecenoic acid
CH3(CH2)7CH=CH(CH2)7COOH
(9Z,12Z)-octadeca-9,12-dienoic acid linoleic acidCH3(CH2)4CH=CHCH2CH=CH(CH2)7COOH
(9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid ALA
α-linolenic acid
cis, cis,cis-9,12,15-octadecatrienoic acid
(Z,Z,Z)-9,12,15-octadecatrienoic acid
CH3CH2CH=CHCH2CH=CHCH2CH=CH(CH2)7COOH
(6Z,9Z,12Z)-octadeca-6,9,12-trienoic acid GLA
γ-linolenic acid
gamolenic acid
CH3(CH2)4CH=CHCH2CH=CHCH2CH=CH(CH2)4COOH
(6Z,9Z,12Z,15Z)-octadeca-6,9,12,15-tetraenoic acid SDA
stearidonic acid
moroctic acid
CH3CH2CH=CHCH2CH=CHCH2CH=CHCH2CH=CH(CH2)5COOH

C19

IUPAC nameCommon nameStructural formula
nonadecanoic acid nonadecylic acidCH3(CH2)17COOH

C20

IUPAC nameCommon nameStructural formula
icosanoic acid arachidic acid
arachic acid
CH3(CH2)18COOH
(5Z,8Z,11Z)-eicosa-5,8,11-trienoic acid Mead's acidCH3(CH2)7CH=CHCH2CH=CHCH2CH=CH(CH2)3COOH
(5Z,8Z,11Z,14Z)-eicosa-5,8,11,14-tetraenoic acid AA
ARA
arachidonic acid
CH3(CH2)4CH=CHCH2CH=CHCH2CH=CHCH2CH=CH(CH2)3COOH
(5Z,8Z,11Z,14Z,17Z)-eicosa-5,8,11,14-pentaenoic acid EPACH3CH2CH=CHCH2CH=CHCH2CH=CHCH2CH=CHCH2CH=CH(CH2)3COOH

C21

IUPAC nameCommon nameStructural formula
heneicosanoic acid CH3(CH2)19COOH

C22

IUPAC nameCommon nameStructural formula
docosanoic acid behenic acidCH3(CH2)20COOH
(4Z,7Z,10Z,13Z,16Z,19Z)-docosa-4,7,10,13,16,19-hexaenoic acid DHA
cervonic acid
CH3CH2CH=CHCH2CH=CHCH2CH=CHCH2CH=CHCH2CH=CHCH2CH=CH(CH2)2COOH

C23

IUPAC nameCommon nameStructural formula
tricosanoic acid tricosylic acidCH3(CH2)21COOH

C24

IUPAC nameCommon nameStructural formula
tetracosanoic acid lignoceric acidCH3(CH2)22COOH

C25

IUPAC nameCommon nameStructural formula
pentacosanoic acid pentacosylic acidCH3(CH2)23COOH

C26

IUPAC nameCommon nameStructural formula
hexacosanoic acid cerotic acidCH3(CH2)24COOH

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