accessibility menu, dialog, popup

UserName

Carbonyl compounds

Organic compounds that contain one or more carbonyl (a carbon atom with a double bond to an oxygen atom) functional groups. Includes compounds with functional groups that contain a carbonyl in their structure such as ketones, aldehydes, and others.
Complex Ketones (2,569)
Complex Aldehydes (1,437)
Dicarbonyl Compounds (330)
Alpha beta-unsaturated carbonyl compounds (322)
Acyloins (34)

Filtered Search Results

Products from some of our suppliers do not display in filtered search results. Please clear all filters to see these products.

Narrow Results

Narrow Results

category

special offers

  • (2,493)
  • (2)

brands

  • (2)
  • (1)
  • (2)
  • (2)
  • (6)
  • (9)
  • (2)
  • (3)
  • (42)
  • (1,998)
  • (2)
  • (2,623)

Quantity

  • (1)
  • (1)
  • (3)
  • (23)
  • (726)
  • (21)
  • (4)
Show all

Molecular Weight (g/mol)

  • (33)
  • (6)
  • (9)
  • (1)
  • (1)
  • (3)
  • (3)
Show all

Percent Purity

  • (1)
  • (2)
  • (4)
  • (6)
  • (1)
  • (26)
  • (13)
Show all

Physical Form

  • (2)
  • (1)
  • (8)
  • (18)
  • (2)
  • (1)
  • (3)
Show all

Boiling Point

  • (2)
  • (3)
  • (3)
  • (2)
  • (17)
  • (1)
  • (3)
Show all

Grade

  • (2)
  • (1)
  • (3)
  • (2)
  • (11)
  • (5)
  • (1)
Show all

Product Line

  • (1)

Search Within Results
Keyword Search:
1 – 15 of 2,353 results
1

2,2-Dimethyl-2,3-dihydro-1-benzofuran-7-carbaldehyde, 97%, Thermo Scientific™

CAS: 38002-88-9 Molecular Formula: C11H12O2 Molecular Weight (g/mol): 176.22 MDL Number: MFCD04115387 InChI Key: HGKYVFOYQUSRQN-UHFFFAOYSA-N Synonym: 2,2-dimethyl-2,3-dihydro-1-benzofuran-7-carbaldehyde,2,2-dimethyl-2,3-dihydrobenzofuran-7-carbaldehyde,7-benzofurancarboxaldehyde, 2,3-dihydro-2,2-dimethyl,2,2-dimethyl-7-formyl-2,3-dihydrobenzofuran,2,2-dimethyl-2,3-dihydro-benzofuran-7-carbaldehyde,2,3-dihydro-2,2-dimethylbenzofuran-7-carbaldehyde,2,2-dimethyl-2,3-dihydrobenzo b furan-7-carbaldehyde,2,3-dihydro-2,2-dimethylbenzofuran-7-carboxaldehyde,2,2-dimethyl-2,3-dihydro-1-benzo b furan-7-carbaldehyde PubChem CID: 2795471 SMILES: CC1(C)CC2=CC=CC(C=O)=C2O1

PubChem CID 2795471
CAS 38002-88-9
Molecular Weight (g/mol) 176.22
MDL Number MFCD04115387
SMILES CC1(C)CC2=CC=CC(C=O)=C2O1
Synonym 2,2-dimethyl-2,3-dihydro-1-benzofuran-7-carbaldehyde,2,2-dimethyl-2,3-dihydrobenzofuran-7-carbaldehyde,7-benzofurancarboxaldehyde, 2,3-dihydro-2,2-dimethyl,2,2-dimethyl-7-formyl-2,3-dihydrobenzofuran,2,2-dimethyl-2,3-dihydro-benzofuran-7-carbaldehyde,2,3-dihydro-2,2-dimethylbenzofuran-7-carbaldehyde,2,2-dimethyl-2,3-dihydrobenzo b furan-7-carbaldehyde,2,3-dihydro-2,2-dimethylbenzofuran-7-carboxaldehyde,2,2-dimethyl-2,3-dihydro-1-benzo b furan-7-carbaldehyde
InChI Key HGKYVFOYQUSRQN-UHFFFAOYSA-N
Molecular Formula C11H12O2
2
Promotions Available

D-(+)-Maltose Monohydrate, Fisher BioReagents

CAS: 6363-53-7 Molecular Formula: C12H24O12 Molecular Weight (g/mol): 360.31 MDL Number: MFCD00149343 InChI Key: HBDJFVFTHLOSDW-UHFFFAOYNA-N Synonym: d-+-maltose monohydrate,unii-dm477ee40d,2r,3r,4r,5r-2,3,5,6-tetrahydroxy-4-2r,3r,4s,5s,6r-3,4,5-trihydroxy-6-hydroxymethyl oxan-2-yl oxy hexanal hydrate,beta-maltose monohydrate,d-+-maltosemonohydrate,69-79-4 anhydrous,d +-maltose monohydrate,d-+-maltose monohydrate, puriss.,d-+-maltose monohydrate, analytical standard,d-+-maltose monohydrate, bioxtra IUPAC Name: 2,3,5,6-tetrahydroxy-4-{[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy}hexanal hydrate SMILES: O.OCC(O)C(OC1OC(CO)C(O)C(O)C1O)C(O)C(O)C=O

CAS 6363-53-7
Molecular Weight (g/mol) 360.31
MDL Number MFCD00149343
SMILES O.OCC(O)C(OC1OC(CO)C(O)C(O)C1O)C(O)C(O)C=O
Synonym d-+-maltose monohydrate,unii-dm477ee40d,2r,3r,4r,5r-2,3,5,6-tetrahydroxy-4-2r,3r,4s,5s,6r-3,4,5-trihydroxy-6-hydroxymethyl oxan-2-yl oxy hexanal hydrate,beta-maltose monohydrate,d-+-maltosemonohydrate,69-79-4 anhydrous,d +-maltose monohydrate,d-+-maltose monohydrate, puriss.,d-+-maltose monohydrate, analytical standard,d-+-maltose monohydrate, bioxtra
IUPAC Name 2,3,5,6-tetrahydroxy-4-{[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy}hexanal hydrate
InChI Key HBDJFVFTHLOSDW-UHFFFAOYNA-N
Molecular Formula C12H24O12
3
Promotions Available

4,4'-Diacetylbiphenyl, 98%

CAS: 787-69-9 Molecular Formula: C16H14O2 Molecular Weight (g/mol): 238.286 MDL Number: MFCD00017248 InChI Key: YSTSBXDVNKYPTR-UHFFFAOYSA-N Synonym: 4,4'-diacetylbiphenyl,4,4'-diacetyl biphenyl,1-4-4-acetylphenyl phenyl ethanone,4,4-diacetylbiphenyl,1,1'-1,1'-biphenyl-4,4'-diyl diethanone,1-4'-acetyl 1,1'-biphenyl-4-yl ethanone,ethanone, 1,1'-1,1'-biphenyl-4,4'-diylbis,1-acetyl-4-4-acetylphenyl benzene,1-4'-acetyl-1,1'-biphenyl-4-yl ethanone,diacetyl biphenyl PubChem CID: 301558 IUPAC Name: 1-[4-(4-acetylphenyl)phenyl]ethanone SMILES: CC(=O)C1=CC=C(C=C1)C2=CC=C(C=C2)C(=O)C

PubChem CID 301558
CAS 787-69-9
Molecular Weight (g/mol) 238.286
MDL Number MFCD00017248
SMILES CC(=O)C1=CC=C(C=C1)C2=CC=C(C=C2)C(=O)C
Synonym 4,4'-diacetylbiphenyl,4,4'-diacetyl biphenyl,1-4-4-acetylphenyl phenyl ethanone,4,4-diacetylbiphenyl,1,1'-1,1'-biphenyl-4,4'-diyl diethanone,1-4'-acetyl 1,1'-biphenyl-4-yl ethanone,ethanone, 1,1'-1,1'-biphenyl-4,4'-diylbis,1-acetyl-4-4-acetylphenyl benzene,1-4'-acetyl-1,1'-biphenyl-4-yl ethanone,diacetyl biphenyl
IUPAC Name 1-[4-(4-acetylphenyl)phenyl]ethanone
InChI Key YSTSBXDVNKYPTR-UHFFFAOYSA-N
Molecular Formula C16H14O2
4

Thermo Scientific Chemicals D-Tagatose, 99%

CAS: 87-81-0 Molecular Formula: C6H12O6 Molecular Weight (g/mol): 180.156 MDL Number: MFCD00134449 InChI Key: BJHIKXHVCXFQLS-PQLUHFTBSA-N Synonym: 3s,4s,5r-1,3,4,5,6-pentahydroxyhexan-2-one,lyxo-2-hexulose,tagatose, d,d--tagatose,keto-d-tagatose,tagatose nf,unii-t7a20y888y,d-lyxo-hex-2-ulose,naturlose PubChem CID: 92092 ChEBI: CHEBI:47693 IUPAC Name: (3S,4S,5R)-1,3,4,5,6-pentahydroxyhexan-2-one SMILES: C(C(C(C(C(=O)CO)O)O)O)O

PubChem CID 92092
CAS 87-81-0
Molecular Weight (g/mol) 180.156
ChEBI CHEBI:47693
MDL Number MFCD00134449
SMILES C(C(C(C(C(=O)CO)O)O)O)O
Synonym 3s,4s,5r-1,3,4,5,6-pentahydroxyhexan-2-one,lyxo-2-hexulose,tagatose, d,d--tagatose,keto-d-tagatose,tagatose nf,unii-t7a20y888y,d-lyxo-hex-2-ulose,naturlose
IUPAC Name (3S,4S,5R)-1,3,4,5,6-pentahydroxyhexan-2-one
InChI Key BJHIKXHVCXFQLS-PQLUHFTBSA-N
Molecular Formula C6H12O6
5
Promotions Available

4-(Trifluoroacetyl)toluene, 97%

CAS: 394-59-2 Molecular Formula: C9H7F3O Molecular Weight (g/mol): 188.149 MDL Number: MFCD00052338 InChI Key: DYILUJUELMWXAL-UHFFFAOYSA-N Synonym: 4-trifluoroacetyl toluene,2,2,2-trifluoro-1-p-tolyl ethanone,4'-methyl-2,2,2-trifluoroacetophenone,2,2,2-trifluoro-1-p-tolylethanone,2,2,2-trifluoro-1-4-methylphenyl ethanone,2,2,2-trifluoro-4'-methylacetophenone,2,2,2-trifluoro-1-4-methylphenyl ethan-1-one,2,2,2-trifluoro-1-p-tolyl-ethanone,4-trifluoroacetyltoluene,acmc-209j5m PubChem CID: 136237 IUPAC Name: 2,2,2-trifluoro-1-(4-methylphenyl)ethanone SMILES: CC1=CC=C(C=C1)C(=O)C(F)(F)F

PubChem CID 136237
CAS 394-59-2
Molecular Weight (g/mol) 188.149
MDL Number MFCD00052338
SMILES CC1=CC=C(C=C1)C(=O)C(F)(F)F
Synonym 4-trifluoroacetyl toluene,2,2,2-trifluoro-1-p-tolyl ethanone,4'-methyl-2,2,2-trifluoroacetophenone,2,2,2-trifluoro-1-p-tolylethanone,2,2,2-trifluoro-1-4-methylphenyl ethanone,2,2,2-trifluoro-4'-methylacetophenone,2,2,2-trifluoro-1-4-methylphenyl ethan-1-one,2,2,2-trifluoro-1-p-tolyl-ethanone,4-trifluoroacetyltoluene,acmc-209j5m
IUPAC Name 2,2,2-trifluoro-1-(4-methylphenyl)ethanone
InChI Key DYILUJUELMWXAL-UHFFFAOYSA-N
Molecular Formula C9H7F3O
6
Promotions Available

Chloroacetone, 96%, stabilized

CAS: 78-95-5 Molecular Formula: C3H5ClO Molecular Weight (g/mol): 92.52 MDL Number: MFCD00000936 InChI Key: BULLHNJGPPOUOX-UHFFFAOYSA-N Synonym: chloroacetone,chloropropanone,acetonyl chloride,monochloroacetone,tonite,2-propanone, 1-chloro,chloro-2-propanone,1-chloroacetone,chloromethyl methyl ketone,1-chloro-2-propanone PubChem CID: 6571 ChEBI: CHEBI:47220 IUPAC Name: 1-chloropropan-2-one SMILES: CC(=O)CCl

PubChem CID 6571
CAS 78-95-5
Molecular Weight (g/mol) 92.52
ChEBI CHEBI:47220
MDL Number MFCD00000936
SMILES CC(=O)CCl
Synonym chloroacetone,chloropropanone,acetonyl chloride,monochloroacetone,tonite,2-propanone, 1-chloro,chloro-2-propanone,1-chloroacetone,chloromethyl methyl ketone,1-chloro-2-propanone
IUPAC Name 1-chloropropan-2-one
InChI Key BULLHNJGPPOUOX-UHFFFAOYSA-N
Molecular Formula C3H5ClO
7
Promotions Available

1,1,1,5,5,5-Hexafluoroacetylacetone, 99%

CAS: 1522-22-1 Molecular Formula: C5H2F6O2 Molecular Weight (g/mol): 208.06 InChI Key: QAMFBRUWYYMMGJ-UHFFFAOYSA-N Synonym: hexafluoroacetylacetone,1,1,1,5,5,5-hexafluoroacetylacetone,1,1,1,5,5,5-hexafluoro-2,4-pentanedione,2,4-pentanedione, 1,1,1,5,5,5-hexafluoro,hexafluoro-2,4-pentanedione,hfac,1,1,1,5,5,5-hexafluoro-2,4-pentadione,1,3-bis trifluoromethyl propane-1,3-dione,1,1,1-trifluoro-3-trifluoroacetyl acetone,2,4-dioxo-1,1,1,5,5,5-hexafluoropentane PubChem CID: 73706 IUPAC Name: 1,1,1,5,5,5-hexafluoropentane-2,4-dione SMILES: C(C(=O)C(F)(F)F)C(=O)C(F)(F)F

PubChem CID 73706
CAS 1522-22-1
Molecular Weight (g/mol) 208.06
SMILES C(C(=O)C(F)(F)F)C(=O)C(F)(F)F
Synonym hexafluoroacetylacetone,1,1,1,5,5,5-hexafluoroacetylacetone,1,1,1,5,5,5-hexafluoro-2,4-pentanedione,2,4-pentanedione, 1,1,1,5,5,5-hexafluoro,hexafluoro-2,4-pentanedione,hfac,1,1,1,5,5,5-hexafluoro-2,4-pentadione,1,3-bis trifluoromethyl propane-1,3-dione,1,1,1-trifluoro-3-trifluoroacetyl acetone,2,4-dioxo-1,1,1,5,5,5-hexafluoropentane
IUPAC Name 1,1,1,5,5,5-hexafluoropentane-2,4-dione
InChI Key QAMFBRUWYYMMGJ-UHFFFAOYSA-N
Molecular Formula C5H2F6O2
8
Promotions Available

2',3'-Difluoroacetophenone, 97%

CAS: 18355-80-1 Molecular Formula: C8H6F2O Molecular Weight (g/mol): 156.13 MDL Number: MFCD00061274 InChI Key: PQUXFUBNSYCQAL-UHFFFAOYSA-N Synonym: 2',3'-difluoroacetophenone,1-2,3-difluorophenyl ethanone,2,3-difluoroacetophenone,1-2,3-difluorophenyl ethan-1-one,ethanone, 1-2,3-difluorophenyl,1-acetyl-2,3-difluorobenzene,pubchem4211,acmc-209x0g,ksc184c5n,2',3'-difluoro acetophenone PubChem CID: 519550 SMILES: CC(=O)C1=CC=CC(F)=C1F

PubChem CID 519550
CAS 18355-80-1
Molecular Weight (g/mol) 156.13
MDL Number MFCD00061274
SMILES CC(=O)C1=CC=CC(F)=C1F
Synonym 2',3'-difluoroacetophenone,1-2,3-difluorophenyl ethanone,2,3-difluoroacetophenone,1-2,3-difluorophenyl ethan-1-one,ethanone, 1-2,3-difluorophenyl,1-acetyl-2,3-difluorobenzene,pubchem4211,acmc-209x0g,ksc184c5n,2',3'-difluoro acetophenone
InChI Key PQUXFUBNSYCQAL-UHFFFAOYSA-N
Molecular Formula C8H6F2O
9
Promotions Available

2',6'-Dimethoxyacetophenone, 98%

CAS: 2040-04-2 MDL Number: MFCD00008729

CAS 2040-04-2
MDL Number MFCD00008729
10
Promotions Available

Octanophenone, 99+%

CAS: 1674-37-9 Molecular Formula: C14H20O Molecular Weight (g/mol): 204.31 MDL Number: MFCD00003554 InChI Key: UDEVCZRUNOLVLU-UHFFFAOYSA-N Synonym: octanophenone,heptyl phenyl ketone,1-octanone, 1-phenyl,caprylophenone,n-octanophenone,ketone, heptyl phenyl,4-n-butylbutyrophenone,1-phenyl-octan-1-one,acmc-1axlq PubChem CID: 74291 IUPAC Name: 1-phenyloctan-1-one SMILES: CCCCCCCC(=O)C1=CC=CC=C1

PubChem CID 74291
CAS 1674-37-9
Molecular Weight (g/mol) 204.31
MDL Number MFCD00003554
SMILES CCCCCCCC(=O)C1=CC=CC=C1
Synonym octanophenone,heptyl phenyl ketone,1-octanone, 1-phenyl,caprylophenone,n-octanophenone,ketone, heptyl phenyl,4-n-butylbutyrophenone,1-phenyl-octan-1-one,acmc-1axlq
IUPAC Name 1-phenyloctan-1-one
InChI Key UDEVCZRUNOLVLU-UHFFFAOYSA-N
Molecular Formula C14H20O
11
Promotions Available

1-Hydroxycyclohexyl phenyl ketone, 98%, Thermo Scientific Chemicals

CAS: 947-19-3 Molecular Formula: C13H16O2 Molecular Weight (g/mol): 204.269 MDL Number: MFCD00059561 InChI Key: QNODIIQQMGDSEF-UHFFFAOYSA-N Synonym: 1-hydroxycyclohexyl phenyl ketone,1-hydroxycyclohexyl phenyl methanone,1-benzoylcyclohexanol,hydroxycyclohexyl phenyl ketone,1-benzoylcyclohexan-1-ol,irgacure 184,methanone, 1-hydroxycyclohexyl phenyl,unii-e7jvn2243x,1-hydroxycyclohexyl-phenylmethanone,1-cyclohexylhydroxyphenylketone PubChem CID: 70355 IUPAC Name: (1-hydroxycyclohexyl)-phenylmethanone SMILES: C1CCC(CC1)(C(=O)C2=CC=CC=C2)O

PubChem CID 70355
CAS 947-19-3
Molecular Weight (g/mol) 204.269
MDL Number MFCD00059561
SMILES C1CCC(CC1)(C(=O)C2=CC=CC=C2)O
Synonym 1-hydroxycyclohexyl phenyl ketone,1-hydroxycyclohexyl phenyl methanone,1-benzoylcyclohexanol,hydroxycyclohexyl phenyl ketone,1-benzoylcyclohexan-1-ol,irgacure 184,methanone, 1-hydroxycyclohexyl phenyl,unii-e7jvn2243x,1-hydroxycyclohexyl-phenylmethanone,1-cyclohexylhydroxyphenylketone
IUPAC Name (1-hydroxycyclohexyl)-phenylmethanone
InChI Key QNODIIQQMGDSEF-UHFFFAOYSA-N
Molecular Formula C13H16O2
12

2-Bromothiophene-3-carbaldehyde, 97%, Thermo Scientific™

CAS: 1860-99-7 Molecular Formula: C5H3BrOS Molecular Weight (g/mol): 191.042 MDL Number: MFCD09025880 InChI Key: MMEGVQIGIBCTHI-UHFFFAOYSA-N PubChem CID: 12245921 IUPAC Name: 2-bromothiophene-3-carbaldehyde SMILES: C1=CSC(=C1C=O)Br

PubChem CID 12245921
CAS 1860-99-7
Molecular Weight (g/mol) 191.042
MDL Number MFCD09025880
SMILES C1=CSC(=C1C=O)Br
IUPAC Name 2-bromothiophene-3-carbaldehyde
InChI Key MMEGVQIGIBCTHI-UHFFFAOYSA-N
Molecular Formula C5H3BrOS
13
Promotions Available

5-Methyl-2-furaldehyde, 98%

CAS: 620-02-0 Molecular Formula: C6H6O2 Molecular Weight (g/mol): 110.112 MDL Number: MFCD00003232 InChI Key: OUDFNZMQXZILJD-UHFFFAOYSA-N Synonym: 5-methylfurfural,5-methyl-2-furaldehyde,5-methyl furfural,5-methyl-2-furfural,2-furancarboxaldehyde, 5-methyl,5-methylfuran-2-al,5-methyl-2-furancarboxaldehyde,5-methylfurfuraldehyde,2-furaldehyde, 5-methyl,2-formyl-5-methylfuran PubChem CID: 12097 ChEBI: CHEBI:2091 IUPAC Name: 5-methylfuran-2-carbaldehyde SMILES: CC1=CC=C(O1)C=O

PubChem CID 12097
CAS 620-02-0
Molecular Weight (g/mol) 110.112
ChEBI CHEBI:2091
MDL Number MFCD00003232
SMILES CC1=CC=C(O1)C=O
Synonym 5-methylfurfural,5-methyl-2-furaldehyde,5-methyl furfural,5-methyl-2-furfural,2-furancarboxaldehyde, 5-methyl,5-methylfuran-2-al,5-methyl-2-furancarboxaldehyde,5-methylfurfuraldehyde,2-furaldehyde, 5-methyl,2-formyl-5-methylfuran
IUPAC Name 5-methylfuran-2-carbaldehyde
InChI Key OUDFNZMQXZILJD-UHFFFAOYSA-N
Molecular Formula C6H6O2
14
Promotions Available

1-Methyl-1H-pyrazole-4-carboxaldehyde, 96%

CAS: 25016-11-9 Molecular Formula: C5H6N2O Molecular Weight (g/mol): 110.116 MDL Number: MFCD00460465 InChI Key: MYFZXSOYJVWTBL-UHFFFAOYSA-N Synonym: 1-methyl-1h-pyrazole-4-carbaldehyde,1-methyl-1h-pyrazole-4-carboxaldehyde,1h-pyrazole-4-carboxaldehyde, 1-methyl,4-formyl-1-methylpyrazole,4-formyl-1-methyl-1h-pyrazole,1-methylpyrazole-4-carboxaldehyde,1-methylpyrazole-4-carboxyaldehyde,1-methyl-1h-pyrazol-4-carbaldehyd,1-methylpyrazole-4-aldehyde,acmc-1cs06 PubChem CID: 573117 IUPAC Name: 1-methylpyrazole-4-carbaldehyde SMILES: CN1C=C(C=N1)C=O

PubChem CID 573117
CAS 25016-11-9
Molecular Weight (g/mol) 110.116
MDL Number MFCD00460465
SMILES CN1C=C(C=N1)C=O
Synonym 1-methyl-1h-pyrazole-4-carbaldehyde,1-methyl-1h-pyrazole-4-carboxaldehyde,1h-pyrazole-4-carboxaldehyde, 1-methyl,4-formyl-1-methylpyrazole,4-formyl-1-methyl-1h-pyrazole,1-methylpyrazole-4-carboxaldehyde,1-methylpyrazole-4-carboxyaldehyde,1-methyl-1h-pyrazol-4-carbaldehyd,1-methylpyrazole-4-aldehyde,acmc-1cs06
IUPAC Name 1-methylpyrazole-4-carbaldehyde
InChI Key MYFZXSOYJVWTBL-UHFFFAOYSA-N
Molecular Formula C5H6N2O
15
Promotions Available

4-Pentenal, 96%

CAS: 2100-17-6 Molecular Formula: C5H8O Molecular Weight (g/mol): 84.12 MDL Number: MFCD00151841 InChI Key: QUMSUJWRUHPEEJ-UHFFFAOYSA-N Synonym: 4-pentenal,4-penten-1-al,acmc-1cdp8,qumsujwruhpeej-uhfffaoysa PubChem CID: 16418 IUPAC Name: pent-4-enal SMILES: C=CCCC=O

PubChem CID 16418
CAS 2100-17-6
Molecular Weight (g/mol) 84.12
MDL Number MFCD00151841
SMILES C=CCCC=O
Synonym 4-pentenal,4-penten-1-al,acmc-1cdp8,qumsujwruhpeej-uhfffaoysa
IUPAC Name pent-4-enal
InChI Key QUMSUJWRUHPEEJ-UHFFFAOYSA-N
Molecular Formula C5H8O