Molecular formula
C18H19N5O2
415 compounds have this formula on CompoundList.
- Molar mass
- 337.38g/mol
- Monoisotopic mass
- 345.2041Da
- Atoms
- 44
- Elements
- 4
- Rings plus double bonds
- 12
The formula C18H19N5O2 describes a molecule made of 18 carbon atoms, 19 hydrogen atoms, 5 nitrogen atoms and 2 oxygen atoms. It is written in Hill notation: carbon first, then hydrogen, then the other elements in alphabetical order. The formula tells you which atoms are present, not how they are connected, which is why several different chemicals can share it.
Elemental composition
- C Carbon × 1864.08%12.011 × 18 = 216.198 g/mol
- H Hydrogen × 195.68%1.008 × 19 = 19.152 g/mol
- N Nitrogen × 520.76%14.007 × 5 = 70.035 g/mol
- O Oxygen × 29.48%15.999 × 2 = 31.998 g/mol
Look up another formula
Compounds with the formula C18H19N5O2
Isomers we list, best known first. Open one to see its structure, properties, safety data and suppliers.
Showing 101 to 200 of 415 compounds
![6-(4-Ethylphenyl)-2,4,7-trimethylpurino[7,8-a]imidazole-1,3-dione chemical structure, C18H19N5O2, CAS 876901-50-7](/s/ABDLBRFTOIBARG-UHFFFAOYSA-N.svg)
6-(4-Ethylphenyl)-2,4,7-trimethylpurino[7,8-a]imidazole-1,3-dione
CAS 876901-50-7C18H19N5O2
3-(2-Methoxyphenyl)-N-(4-methylphenyl)-2-(2H-tetrazol-5-yl)propanamide
CAS 483993-60-8C18H19N5O2
3-(4-Methoxyphenyl)-N-(4-methylphenyl)-2-(2H-tetrazol-5-yl)propanamide
CAS 483993-01-7C18H19N5O2
![8-(3,4-Dimethylphenyl)-1,3,7-trimethyl-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione chemical structure, C18H19N5O2, CAS 893367-89-0](/s/MKNYMLDLJFGWBI-UHFFFAOYSA-N.svg)
8-(3,4-Dimethylphenyl)-1,3,7-trimethyl-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione
CAS 893367-89-0C18H19N5O2
5H-Pyridazino(4,5-b)indol-4-amine, 7,8-dimethoxy-N-(2,5-dimethyl-1H-pyrrol-1-yl)-
CAS 121638-63-9C18H19N5O2
![2,4,7-Trimethyl-6-[(3-methylphenyl)methyl]purino[7,8-a]imidazole-1,3-dione chemical structure, C18H19N5O2, CAS 878421-17-1](/s/RECBAQCIEJDRCP-UHFFFAOYSA-N.svg)
2,4,7-Trimethyl-6-[(3-methylphenyl)methyl]purino[7,8-a]imidazole-1,3-dione
CAS 878421-17-1C18H19N5O2
![6-(2,3-Dimethylphenyl)-2,4,7-trimethylpurino[7,8-a]imidazole-1,3-dione chemical structure, C18H19N5O2, CAS 878420-43-0](/s/TUGVIEVNUUMNMD-UHFFFAOYSA-N.svg)
6-(2,3-Dimethylphenyl)-2,4,7-trimethylpurino[7,8-a]imidazole-1,3-dione
CAS 878420-43-0C18H19N5O2
![6-(2,4-Dimethylphenyl)-2,4,7-trimethylpurino[7,8-a]imidazole-1,3-dione chemical structure, C18H19N5O2, CAS 878727-17-4](/s/HOIJPZQSYXLBRJ-UHFFFAOYSA-N.svg)
6-(2,4-Dimethylphenyl)-2,4,7-trimethylpurino[7,8-a]imidazole-1,3-dione
CAS 878727-17-4C18H19N5O2
![2-Ethyl-4,7,8-trimethyl-6-phenylpurino[7,8-a]imidazole-1,3-dione chemical structure, C18H19N5O2, CAS 877644-44-5](/s/RQKLYCHJUZLRQK-UHFFFAOYSA-N.svg)
2-Ethyl-4,7,8-trimethyl-6-phenylpurino[7,8-a]imidazole-1,3-dione
CAS 877644-44-5C18H19N5O2
![2-[2-(3,5-Dimethylpyrazol-1-yl)-4-methyl-6-oxopyrimidin-1-yl]-N-phenylacetamide chemical structure, C18H19N5O2, CAS 1001797-93-8](/s/RKBCMUDQBCNGHX-UHFFFAOYSA-N.svg)
2-[2-(3,5-Dimethylpyrazol-1-yl)-4-methyl-6-oxopyrimidin-1-yl]-N-phenylacetamide
CAS 1001797-93-8C18H19N5O2
![2-[2-(4-Pyrimidin-2-ylpiperazin-1-yl)ethyl]isoindole-1,3-dione chemical structure, C18H19N5O2, CAS 95847-91-9](/s/SJFQBFYOIPUMAL-UHFFFAOYSA-N.svg)
2-[2-(4-Pyrimidin-2-ylpiperazin-1-yl)ethyl]isoindole-1,3-dione
CAS 95847-91-9C18H19N5O2
![7-Ethyl-6-imino-13-methyl-2-oxo-N-(prop-2-en-1-yl)-1,7,9-triazatricyclo[8.4.0.0^{3,8}]tetradeca-3(8),4,9,11,13-pentaene-5-carboxamide chemical structure, C18H19N5O2, CAS 862705-12-2](/s/WCPQHNKPZFNSFQ-UHFFFAOYSA-N.svg)
7-Ethyl-6-imino-13-methyl-2-oxo-N-(prop-2-en-1-yl)-1,7,9-triazatricyclo[8.4.0.0^{3,8}]tetradeca-3(8),4,9,11,13-pentaene-5-carboxamide
CAS 862705-12-2C18H19N5O2
![1,6,7-Trimethyl-3-(3-methylbenzyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione chemical structure, C18H19N5O2, CAS 919012-44-5](/s/QKWWSLWTOWMVAS-UHFFFAOYSA-N.svg)
1,6,7-Trimethyl-3-(3-methylbenzyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione
CAS 919012-44-5C18H19N5O2
![3-Ethyl-1,7-dimethyl-8-(p-tolyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione chemical structure, C18H19N5O2, CAS 877643-60-2](/s/ALTRVNGZHHEBLK-UHFFFAOYSA-N.svg)
3-Ethyl-1,7-dimethyl-8-(p-tolyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione
CAS 877643-60-2C18H19N5O2
![3-(2,5-Dimethylbenzyl)-1,7-dimethyl-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione chemical structure, C18H19N5O2, CAS 923461-16-9](/s/WGFAFDKZUJBAGJ-UHFFFAOYSA-N.svg)
3-(2,5-Dimethylbenzyl)-1,7-dimethyl-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione
CAS 923461-16-9C18H19N5O2
5-Amino-1-(2,5-dimethylphenyl)-N-(2-methoxyphenyl)-1H-1,2,3-triazole-4-carboxamide
CAS 953849-72-4C18H19N5O2
5-Amino-1-benzyl-N-(2-methoxy-5-methylphenyl)-1H-1,2,3-triazole-4-carboxamide
CAS 902470-28-4C18H19N5O2
3-(3-Methoxyphenyl)-N-(2-methylphenyl)-2-(2H-tetrazol-5-yl)propanamide
CAS 483993-26-6C18H19N5O2
3-(4-Methoxyphenyl)-N-(2-methylphenyl)-2-(2H-tetrazol-5-yl)propanamide
CAS 483993-03-9C18H19N5O2
![2-(Benzo[d]isoxazol-3-yl)-1-(4-(6-methylpyridazin-3-yl)piperazin-1-yl)ethanone chemical structure, C18H19N5O2, CAS 1207023-42-4](/s/JKTDOISGYVBOOI-UHFFFAOYSA-N.svg)
2-(Benzo[d]isoxazol-3-yl)-1-(4-(6-methylpyridazin-3-yl)piperazin-1-yl)ethanone
CAS 1207023-42-4C18H19N5O2
1-Methyl-N-(3-(6-oxopyridazin-1(6H)-yl)propyl)-3-phenyl-1H-pyrazole-5-carboxamide
CAS 1209434-37-6C18H19N5O2
N-(2-(1H-Pyrazol-1-yl)pyrimidin-5-yl)-4-butoxybenzamide
CAS 1421490-38-1C18H19N5O2
![N-[2-(3,5-Dimethyl-1H-pyrazol-1-yl)pyrimidin-5-yl]-2-phenoxypropanamide chemical structure, C18H19N5O2, CAS 1421509-81-0](/s/DWOBGYKZCNRKOK-UHFFFAOYSA-N.svg)
N-[2-(3,5-Dimethyl-1H-pyrazol-1-yl)pyrimidin-5-yl]-2-phenoxypropanamide
CAS 1421509-81-0C18H19N5O2
![3-Methoxy-1-methyl-N-(3-{5H,6H,7H-pyrrolo[1,2-a]imidazol-3-yl}phenyl)-1H-pyrazole-4-carboxamide chemical structure, C18H19N5O2, CAS 1428349-56-7](/s/DWRIDBCBWNHHDY-UHFFFAOYSA-N.svg)
3-Methoxy-1-methyl-N-(3-{5H,6H,7H-pyrrolo[1,2-a]imidazol-3-yl}phenyl)-1H-pyrazole-4-carboxamide
CAS 1428349-56-7C18H19N5O2
- N-(2-((6-(1H-Pyrrol-1-yl)pyrimidin-4-yl)amino)ethyl)-2-phenoxyacetamide1396760-52-3C18H19N5O2
- 1-Methyl-N-(4-morpholin-4-ylphenyl)benzotriazole-5-carboxamide695174-41-5C18H19N5O2
- 4-Phenylmethoxy-N-(2-propyltetrazol-5-yl)benzamide593241-44-2C18H19N5O2
- 3-(2-Methoxyphenyl)-N-(3-methylphenyl)-2-(2H-1,2,3,4-tetrazol-5-yl)propanamide483993-61-9C18H19N5O2
- 3-(3-Methoxyphenyl)-N-(4-methylphenyl)-2-(2H-tetrazol-5-yl)propanamide483993-24-4C18H19N5O2
- 1,3,6,7-Tetramethyl-8-(m-tolyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione36183-86-5C18H19N5O2
- 8-(2,5-Dimethylphenyl)-1,6,7-trimethyl-1,3,5-trihydro-4-imidazolino[1,2-h]puri ne-2,4-dione878732-53-7C18H19N5O2
- 5-(2-Oxo-2-(pyrrolidin-1-yl)ethyl)-1-(p-tolyl)-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-one863446-27-9C18H19N5O2
- 4,7-Dimethyl-6-phenyl-2-propylpurino[7,8-a]imidazole-1,3-dione887463-71-0C18H19N5O2
- N-(4-Ethoxyphenyl)-2-[5-(4-methylphenyl)tetrazol-2-yl]acetamide926116-85-0C18H19N5O2
- 1,6,7-Trimethyl-3-(2-methylbenzyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione919031-53-1C18H19N5O2
- 3-Benzyl-8-ethyl-1,7-dimethyl-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione887462-31-9C18H19N5O2
- 1,7,8-Trimethyl-3-(3-methylbenzyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione887461-41-8C18H19N5O2
- 5-Amino-N-benzyl-1-(4-ethoxyphenyl)-1H-1,2,3-triazole-4-carboxamide951894-32-9C18H19N5O2
- 5-Amino-1-(3,5-dimethylphenyl)-N-(3-methoxyphenyl)-1H-1,2,3-triazole-4-carboxamide1032229-31-4C18H19N5O2
- N-(2-(5-Benzyl-4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyrimidin-1-yl)ethyl)cyclopropanecarboxamide922130-81-2C18H19N5O2
- 1-[2-(4-Methylphenyl)-2H-pyrazolo[4,3-d]pyrimidin-7-yl]piperidine-4-carboxylic acid1170135-79-1C18H19N5O2
- (1H-Benzo[d]imidazol-5-yl)(4-(5-cyclopropyl-1,3,4-oxadiazol-2-yl)piperidin-1-yl)methanone1210475-42-5C18H19N5O2
- N-(3-{[2-(1H-indol-3-yl)ethyl]amino}-3-oxopropyl)-2-pyrazinecarboxamide1374520-43-0C18H19N5O2
- N-[2-(3,5-Dimethyl-1H-pyrazol-1-yl)pyrimidin-5-yl]-4-ethoxybenzamide1396794-82-3C18H19N5O2
- N-(2-(1H-Imidazol-1-yl)pyrimidin-5-yl)-4-butoxybenzamide1421490-51-8C18H19N5O2
- N-(2-Ethylphenyl)-2-{[2-methyl-6-(1H-pyrazol-1-yl)pyrimidin-4-yl]oxy}acetamide1421443-88-0C18H19N5O2
- 2-((2-Methyl-6-(1H-pyrazol-1-yl)pyrimidin-4-yl)oxy)-N-phenethylacetamide1421514-10-4C18H19N5O2
- N-(2-((6-(1H-Pyrrol-1-yl)pyrimidin-4-yl)amino)ethyl)-2-methoxybenzamide1421482-86-1C18H19N5O2
- N-(2-(5-Cyclopropyl-3-(pyridin-4-yl)-1H-pyrazol-1-yl)ethyl)-5-methylisoxazole-4-carboxamide1797260-36-6C18H19N5O2
- 1-(3-Methoxyphenyl)-3-(2-(2-(pyridin-2-yl)-1H-imidazol-1-yl)ethyl)urea2034506-26-6C18H19N5O2
- N-{5H,6H,7H,8H-imidazo[1,2-a]pyridin-6-yl}-2-(2-methyl-4-oxo-3,4-dihydroquinazolin-3-yl)acetamide1795469-51-0C18H19N5O2
- 2-(1H-Benzo[d]imidazol-1-yl)-1-(3-(pyridazin-3-yloxy)piperidin-1-yl)ethanone2034583-01-0C18H19N5O2
- 2-(4-Oxoquinazolin-3(4H)-yl)-N-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyridin-3-yl)methyl)acetamide2034340-69-5C18H19N5O2
- 3-[(3-Methylpiperidin-1-yl)carbonyl]-6-phenyl[1,2,3]triazolo[1,5-a]pyrazin-4(5H)-one2108215-30-9C18H19N5O2
- 3-[(4-Methylpiperidin-1-yl)carbonyl]-6-phenyl[1,2,3]triazolo[1,5-a]pyrazin-4(5H)-one2108716-28-3C18H19N5O2
- N-(3-Methyl-1-(4-methyl-6-oxo-1,6-dihydropyrimidin-2-yl)-1H-pyrazol-5-yl)-3-phenylpropanamide1052604-58-6C18H19N5O2
- N-[1-(4,5-Dimethyl-6-oxo-1,6-dihydropyrimidin-2-yl)-3-methyl-1H-pyrazol-5-yl]-2-phenylacetamide1052607-89-2C18H19N5O2
- 4-N,6-N-bis(4-methoxyphenyl)pyrimidine-2,4,6-triamine5471-66-9C18H19N5O2
- Ethyl 4-[2,5-dimethyl-3-[(Z)-1,2,4-triazol-4-yliminomethyl]pyrrol-1-yl]benzoateC18H19N5O2
- 2-(3-Nitrophenyl)-3-(piperazin-1-ylmethyl)imidazo[1,2-a]pyridine727975-37-3C18H19N5O2
- N-[4-(Dimethylamino)phenyl]-3-(4-oxo-1,2,3-benzotriazin-3(4H)-yl)propanamide900871-46-7C18H19N5O2
- 8-(2,4-Dimethylphenyl)-1,6,7-trimethyl-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione878732-20-8C18H19N5O2
- (2-(Pyrid-4-yl)-1H-benzimidazole-4-carbonyl)-(L)-valinamide316832-39-0C18H19N5O2
- N-[4-(Acetylamino)phenyl]-1,3,6-trimethyl-1H-pyrazolo[3,4-b]pyridine-4-carboxamide938883-43-3C18H19N5O2
- 3-Ethyl-1,7-dimethyl-8-(m-tolyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione887464-26-8C18H19N5O2
- 1,7-Dimethyl-3-(3-phenylpropyl)-1H-imidazo[2,1-f]purine-2,4(3H,8H)-dione921069-66-1C18H19N5O2
- N-(4-Oxo-1-(p-tolyl)-1H-pyrazolo[3,4-d]pyrimidin-5(4H)-yl)cyclopentanecarboxamide899736-97-1C18H19N5O2
- 5-Amino-1-(2,5-dimethylphenyl)-N-(4-methoxyphenyl)-1H-1,2,3-triazole-4-carboxamide950249-19-1C18H19N5O2
- 5-Amino-1-(4-ethoxyphenyl)-N-methyl-N-phenyl-1H-1,2,3-triazole-4-carboxamide953847-99-9C18H19N5O2
- 5-Amino-N-(2,5-dimethylphenyl)-1-(4-methoxyphenyl)-1H-1,2,3-triazole-4-carboxamide953848-28-7C18H19N5O2
- 5-Amino-N-(2,3-dimethylphenyl)-1-(4-methoxyphenyl)-1H-1,2,3-triazole-4-carboxamide953850-17-4C18H19N5O2
- 5-Amino-N-(4-ethoxyphenyl)-1-(4-methylphenyl)-1H-1,2,3-triazole-4-carboxamide929835-45-0C18H19N5O2
- 1,4-Dimethyl-N-[5-(5,6,7,8-tetrahydronaphthalen-2-yl)-1,3,4-oxadiazol-2-yl]-1H-pyrazole-3-carboxamide1206995-90-5C18H19N5O2
- 2-(1-Oxo-7,8,9,10-tetrahydro-[1,2,4]triazino[4,5-b]indazol-2(1H)-yl)-N-(o-tolyl)acetamide1031981-83-5C18H19N5O2
- N-[2-(2-Methoxyphenyl)ethyl]-4-(1H-tetrazol-1-ylmethyl)benzamide1219558-35-6C18H19N5O2
- N-Benzyl-2-(3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-oxopyridazin-1(6H)-yl)acetamide1219539-94-2C18H19N5O2
- (3,6-Dimethyl[1,2]oxazolo[5,4-b]pyridin-4-yl)[4-(pyridin-2-yl)piperazin-1-yl]methanone1282096-72-3C18H19N5O2
- N-[3-(1H-Imidazol-1-yl)propyl]-3-[(6-methylpyridazin-3-yl)oxy]benzamide1251545-16-0C18H19N5O2
- N-(2-(6-Oxo-3-(1H-pyrazol-1-yl)pyridazin-1(6H)-yl)ethyl)-2-(o-tolyl)acetamide1351607-51-6C18H19N5O2
- N-(2-Methoxyethyl)-3-[4-(2-pyridinylamino)phenoxy]-2-pyrazinamine1231921-87-1C18H19N5O2
- N-[2-(3,5-Dimethyl-1H-pyrazol-1-yl)pyrimidin-5-yl]-2-(4-methoxyphenyl)acetamide1421473-41-7C18H19N5O2
- 2-Methoxy-N-(2-(3,4,5-trimethyl-1H-pyrazol-1-yl)pyrimidin-5-yl)benzamide1421473-57-5C18H19N5O2
- N-(2-(3-(1H-Imidazol-1-yl)-6-oxopyridazin-1(6H)-yl)ethyl)-3,4-dimethylbenzamide1396749-16-8C18H19N5O2
- N-(4-(4-Methyl-5-oxo-4,5-dihydro-1H-tetrazol-1-yl)phenyl)-2-phenylbutanamide1396795-47-3C18H19N5O2
- 2-(4-Methoxyphenyl)-N-(3-phenylpropyl)-2H-tetrazole-5-carboxamide1396713-36-2C18H19N5O2
- N-Ethyl-2-(4-methoxyphenyl)-N-(o-tolyl)-2H-tetrazole-5-carboxamide1396791-48-2C18H19N5O2
- N-(2-Isopropylphenyl)-2-(4-methoxyphenyl)-2H-tetrazole-5-carboxamide1396878-48-0C18H19N5O2
- N-(2-((6-(1H-Pyrrol-1-yl)pyridazin-3-yl)amino)ethyl)-3-methoxybenzamide1428378-00-0C18H19N5O2
- N-(2-((6-(1H-Pyrrol-1-yl)pyridazin-3-yl)amino)ethyl)-2-phenoxyacetamide1396815-95-4C18H19N5O2
- (E)-3-(Furan-2-yl)-N-(2-((2-methyl-6-(1H-pyrrol-1-yl)pyrimidin-4-yl)amino)ethyl)acrylamide1396890-20-2C18H19N5O2
- N-(6-(1H-Pyrazol-1-yl)pyrimidin-4-yl)-2-(2,5-dimethylphenoxy)propanamide1428366-70-4C18H19N5O2
- (1H-Benzo[d]imidazol-5-yl)(3-((6-methylpyridazin-3-yl)oxy)piperidin-1-yl)methanone2034576-85-5C18H19N5O2
- 3-(1H-Benzo[d]imidazol-1-yl)-N-(3-oxo-2,3,5,6,7,8-hexahydrocinnolin-6-yl)propanamide2034348-94-0C18H19N5O2
- N-((1H-Benzo[d]imidazol-2-yl)methyl)-2-methyl-3-oxo-2,3,5,6,7,8-hexahydrocinnoline-6-carboxamide1903559-03-4C18H19N5O2
- 2-(1H-Imidazol-1-yl)-1-(3-(3-methyl-1,2,4-oxadiazol-5-yl)-4-phenylpyrrolidin-1-yl)ethanone1903048-91-8C18H19N5O2
- 1-(3-(3-Methyl-1,2,4-oxadiazol-5-yl)-4-phenylpyrrolidin-1-yl)-2-(1H-pyrazol-1-yl)ethanone1903170-17-1C18H19N5O2
- 2-(3-Methoxyphenyl)-N-{2-[3-(pyrazin-2-yl)-1H-pyrazol-1-yl]ethyl}acetamide2034548-07-5C18H19N5O2
- 4-Isopropoxy-N-((1-(pyridin-3-yl)-1H-1,2,3-triazol-4-yl)methyl)benzamide2034311-45-8C18H19N5O2
- N-(3-Methyl-1-(6-oxo-4-propyl-1,6-dihydropyrimidin-2-yl)-1H-pyrazol-5-yl)benzamide1052604-99-5C18H19N5O2
- 3,5-Dimethyl-N-(3-methyl-1-(4-methyl-6-oxo-1,6-dihydropyrimidin-2-yl)-1H-pyrazol-5-yl)benzamide1019099-42-3C18H19N5O2
Frequently asked questions
What is the molar mass of C18H19N5O2?
The molar mass of C18H19N5O2 is 337.38 g/mol, calculated from standard atomic weights for 18 carbon atoms, 19 hydrogen atoms, 5 nitrogen atoms and 2 oxygen atoms. The monoisotopic mass is 345.2041 Da.
How many compounds have the formula C18H19N5O2?
CompoundList lists 415 compounds with the molecular formula C18H19N5O2, including 6-(4-Ethylphenyl)-2,4,7-trimethylpurino[7,8-a]imidazole-1,3-dione, 3-(2-Methoxyphenyl)-N-(4-methylphenyl)-2-(2H-tetrazol-5-yl)propanamide, 3-(4-Methoxyphenyl)-N-(4-methylphenyl)-2-(2H-tetrazol-5-yl)propanamide. Compounds that share a formula are isomers. They contain the same atoms arranged differently, so their properties, uses and prices can be very different.
What is the degree of unsaturation of C18H19N5O2?
C18H19N5O2 has a degree of unsaturation of 12. That is the total number of rings and pi bonds (a double bond counts as one, a triple bond as two) in any structure with this formula.