This is a partial list of molecules that contain 18 carbon atoms.
| Chemical formula | Synonyms | CAS number |
|---|---|---|
| C18F39N | perfluorotrihexylamine | 432-08-6 |
| C18H8S4 | tetrathianaphthacene | 193-44-2 |
| C18H10Cl2O2S2 | c.i. vat red 1 | 2379-74-0 |
| C18H10Cl2O2S2 | c.i. vat violet 2 | 5462-29-3 |
| C18H11N3O7 | acenaphthene picric acid | 4599-99-9 |
| C18H12 | chrysene | 218-01-9 |
| C18H12 | naphthacene | 92-24-0 |
| C18H12 | triphenylene | 217-59-4 |
| C18H13ClN2O | pinazepam | 52463-83-9 |
| C18H13O | pentaethylacetophenone | 500021-17-0 |
| C18H14 | dihydrochrysene | 41593-31-1 |
| C18H14 | terphenyl | 26140-60-3 |
| C18H14ClFN2O3 | ethyl loflazepate | 29177-84-2 |
| C18H14Cl4N2O | miconazole | 22916-47-8 |
| C18H14O4 | dicinnamoyl peroxide | 15036-31-4 |
| C18H15BrCoN2O2P | triphenylphosphinecobalt dinitrosyl bromide | 14318-88-8 |
| C18H15BrFeN2O2P | triphenylphosphineiron dinitrosyl bromide | 38831-62-8 |
| C18H15BrGe | triphenylgermanium bromide | 3005-32-1 |
| C18H15ClSi | triphenylchlorosilane | 76-86-8 |
| C18H15ClSn | chlorotriphenyl tin | 639-58-7 |
| C18H15CoIN2O2P | triphenylphosphinecobalt dinitrosyl iodide | 14318-98-0 |
| C18H15FSi | fluorotriphenylsilane | 379-50-0 |
| C18H15FeIN2O2P | triphenylphosphineiron dinitrosyl iodide | 14588-79-5 |
| C18H15ISn | triphenyltin iodide | 894-09-7 |
| C18H15OP | phenyl diphenylphosphinite | 13360-92-4 |
| C18H15O3P | phenyl phosphonic acid diphenyl ester | 3049-24-9 |
| C18H15O4P | triphenylphosphate | 115-86-6 |
| C18H15PSe | triphenylphosphine selenide | 3878-44-2 |
| C18H16Cr | benzenebiphenylchromium | 12095-46-4 |
| C18H16O2 | cinnamyl cinnamate | 122-69-0 |
| C18H16O2 | retenequinone | 5398-75-4 |
| C18H16O2Si | dianisyldiethynylsilane | 55986-09-9 |
| C18H16O3 | phenprocoumon | 435-97-2 |
| C18H16O4 | dibenzyl maleate | 62-26-0 |
| C18H16O7 | Several molecules | – |
| C18H16Sn | triphenyltin hydride | 892-20-6 |
| C18H17ClN2O2 | oxazolam | 24143-17-7 |
| C18H17Cl2NO3 | benzoylprop ethyl | 22212-55-1 |
| C18H17NSi | triphenylsilanamine | 4215-80-9 |
| C18H17O7 | Several molecules | – |
| C18H18BrClN2O | metaclazepam | 65517-27-3 |
| C18H18ClNS | chlorprothixene | 113-59-7 |
| C18H18ClN2O2P | fosazepam | 35322-07-7 |
| C18H18ClN3O | loxapine | 1977-10-2 |
| C18H18ClN3S | clothiapine | 2058-52-8 |
| C18H18N2O2 | phenylalanylanhydride | 2308-61-4 |
| C18H18N2O5 | ethyl azoxybenzenedicarboxylate | 6421-04-1 |
| C18H18O2 | dienestrol | 84-17-3 |
| C18H18O2 | equilenin acetate | 517-09-9 |
| C18H18O4 | diphenyl adipate | 3195-37-7 |
| C18H19ClN4 | clozapine | 5786-21-0 |
| C18H19F3N2S | triflupromazine | 146-54-3 |
| C18H19N | benzoctamine | 17243-39-9 |
| C18H19NO | nordoxepin | 1225-56-5 |
| C18H19NOS | duloxetine | 116539-59-4 |
| C18H19NO5 | melicopicine | 517-73-7 |
| C18H20Cl2 | perthane | 72-56-0 |
| C18H20N2S | methdilazine | 1982-37-2 |
| C18H20N2S | pyrathiazine | 84-08-2 |
| C18H20O2 | diethylstilbesterol | 56-53-1 |
| C18H21ClN2 | chlorcyclizine | 82-93-9 |
| C18H21NO | azacyclonol | 115-46-8 |
| C18H21NO2 | methyldesorphine | 16008-36-9 |
| C18H21NO3 | codeine | 76-57-3 |
| C18H21NO3 | hydrocodone | 125-29-1 |
| C18H21NO3 | neopine | 467-14-1 |
| C18H21NO4 | oxycodone | 76-42-6 |
| C18H21N3O | dibenzepin | 4498-32-2 |
| C18H21OP | diphenylcyclohexylphosphine oxide | 13689-20-8 |
| C18H22BrNO | embramine | 3565-72-8 |
| C18H22ClNO | chlorphenoxamine | 77-38-3 |
| C18H22ClNO | phenoxybenzamine | 59-96-1 |
| C18H22N2 | cyclizine | 82-92-8 |
| C18H22N2 | desipramine | 50-47-5 |
| C18H22N2OS | methoxypromazine | 61-01-8 |
| C18H22N2O2S | oxomemazine | 3689-50-7 |
| C18H22N2S | diethazine | 60-91-3 |
| C18H22N2S | trimeprazine | 84-96-8 |
| C18H22O2 | hexoestrol | 84-16-2 |
| C18H22O5 | zearalenone | 18695-28-8 |
| C18H22O8 | tetraethylpyromellitate | 6634-01-1 |
| C18H23N | tolpropamide | 5632-44-0 |
| C18H23NO | orphenadrine | 83-98-7 |
| C18H23NO3 | dihydrocodeine | 125-28-0 |
| C18H23NO3 | isoxsuprine | 395-28-8 |
| C18H23NO3 | methyldihydromorphine | 509-56-8 |
| C18H23NO4 | ethylbenzoylecgonine | 529-38-4 |
| C18H23NO5 | seneciphylline | 480-81-9 |
| C18H23NO5 | spartioidine | 520-59-2 |
| C18H23NO6 | jacozine | 5532-23-0 |
| C18H23NO6 | riddelliine | 23246-96-0 |
| C18H23NO7 | senecicannabine | 81855-31-4 |
| C18H23N5O2 | fenethylline | 1892-80-4 |
| C18H24 | triamantane | 13349-10-5 |
| C18H24 | estrin | 1217-09-0 |
| C18H24N2O6 | dinocap | 39300-45-3 |
| C18H24O2 | geranyl phenylacetate | 102-22-7 |
| C18H24O3 | estriol | 50-27-1 |
| C18H24O6 | butylphthalyl butyl glycolate | 85-70-1 |
| C18H25NO | cyclazocine | 3572-80-3 |
| C18H25NO | dextromethorphan | 125-71-3 |
| C18H25NO | racemethorphan | 510-53-2 |
| C18H25NO2 | allylprodine | 25384-17-2 |
| C18H25NO5 | doronenine | 74217-57-5 |
| C18H25NO5 | integerrimine | 480-79-5 |
| C18H25NO5 | senecionine | 130-01-8 |
| C18H25NO5 | triangularine | 87340-27-0 |
| C18H25NO6 | retrorsine | 480-54-6 |
| C18H25NO6 | usaramine | 15503-87-4 |
| C18H26ClNO6 | jaconine | 480-75-1 |
| C18H26ClN3 | chloroquine | 54-05-7 |
| C18H26ClN3O | hydroxychloroquine | 118-42-3 |
| C18H26O | versalide | 88-29-9 |
| C18H26O4 | dipentyl terephthalate | 1818-95-7 |
| C18H26O4 | heptyl benzyl succinate | 119450-15-6 |
| C18H26O12 | hexaacetylmannitol | 5346-76-9 |
| C18H27NO2 | caramiphen | 77-22-5 |
| C18H27NO4 | etoxeridine | 469-82-9 |
| C18H27NO5 | platyphylline | 480-78-4 |
| C18H27NO5 | propanidid | 1421-14-3 |
| C18H27NO6 | rosmarinine | 520-65-0 |
| C18H27NO7 | jacoline | 480-76-2 |
| C18H27NO7 | sceleratine | 6190-25-6 |
| C18H27N3O | pentaquin | 86-78-2 |
| C18H27P | dicyclohexylphenylphosphine | 6476-37-5 |
| C18H28 | cyclododecylbenzene | 15971-88-7 |
| C18H28N2O4 | acebutolol | 37517-30-9 |
| C18H28N2O3S | almokalant | 123955-10-2 |
| C18H28N4O | butalamine | 22131-35-7 |
| C18H28O | dodecanophenone | 1674-38-0 |
| C18H29NO2 | ketocaine | 1092-46-2 |
| C18H29NO3 | amprotropine | 148-32-3 |
| C18H29NO4 | guaiapate | 852-42-6 |
| C18H30 | perhydrochrysene | 2090-14-4 |
| C18H30BaCa2O12 | barium dicalcium propionate | 17115-98-9 |
| C18H30Ca2O12Pb | lead dicalcium propionate | 17203-66-6 |
| C18H30Ca2O12Sr | strontium dicalcium propionate | 54993-39-4 |
| C18H30 | estrane | |
| C18H30O | farnesyl acetone | 1117-52-8 |
| C18H30O | linolenyl aldehyde | 2423-13-4 |
| C18H30O2 | alpha-linolenic acid | 463-40-1 |
| C18H30O2 | gamma-linolenic acid | 506-26-3 |
| C18H30O4 | dicyclohexyl adipate | 849-99-0 |
| C18H32O | linoleyl aldehyde | 2541-61-9 |
| C18H32O2 | linoleic acid | 60-33-3 |
| C18H32O2 | linoelaidic acid | 506-21-8 |
| C18H32O2 | stearolic acid | 506-24-1 |
| C18H32O7 | butyl citrate | 77-94-1 |
| C18H33Cl3O2 | hexadecyl trichloroacetate | 74339-54-1 |
| C18H33NO | linoleamide | 3999-01-7 |
| C18H34N2O6S | lincomycin | 154-21-2 |
| C18H34O | cyclooctadecanone | 6907-37-5 |
| C18H34O2 | oleic acid | 2027-47-6 |
| C18H34O3 | castor oil | 8001-79-4 |
| C18H34O3 | ricinoleic acid | 141-22-0 |
| C18H34O4 | octadecanedioic acid | 871-70-5 |
| C18H35BrO2 | hexadecyl bromoacetate | 5454-48-8 |
| C18H35ClO | stearic acid chloride | 112-76-5 |
| C18H35ClO2 | hexadecyl chloroacetate | 52132-58-8 |
| C18H35N | octadecanenitrile | 638-65-3 |
| C18H35NO | elaidamide | 4303-70-2 |
| C18H35O2Tl | thallium octadecanoate | 33734-56-4 |
| C18H36 | cyclooctadecane | 296-18-4 |
| C18H36 | dodecylcyclohexane | 1795-17-1 |
| C18H36 | hexaethylcyclohexane | 98803-61-3 |
| C18H36N2NiS4 | nickel diisobutyldithiocarbamate | 15317-78-9 |
| C18H36O | oleyl alcohol | 143-28-2 |
| C18H36O | stearaldehyde | 638-66-4 |
| C18H36O2 | hexyl dodecanoate | 34316-64-8 |
| C18H36O2 | octadecanoic acid | 57-11-4 |
| C18H36O3 | octadecaneperoxoic acid | 5796-86-1 |
| C18H37NO | octadecanamide | 124-26-5 |
| C18H37NO5 | sarracine | 2492-09-3 |
| C18H38 | octadecane | 593-45-3 |
| C18H38N2O | stearic acid hydrazide | 4130-54-5 |
| C18H38O4Si2 | dodecanedioic acid di tms | 22396-19-6 |
| C18H38O7 | hexapropylene glycol | 52794-80-6 |
| C18H38S | dinonyl sulfide | 929-98-6 |
| C18H39BrSi | bromotrihexylsilane | 11643-50-8 |
| C18H39N | dinonylamine | 2044-21-5 |
| C18H39O3P | trihexyl phosphite | 6095-42-7 |
| C18H41NO2Si2 | leucine ditbdms | 92771-65-8 |
| C18H54Si8 | octadecamethyloctasilane | 3704-48-1 |