Molecular formula
C15H21ClN2O3
210 compounds have this formula on CompoundList.
- Molar mass
- 312.79g/mol
- Monoisotopic mass
- 312.1241Da
- Atoms
- 42
- Elements
- 5
- Rings plus double bonds
- 6
The formula C15H21ClN2O3 describes a molecule made of 15 carbon atoms, 21 hydrogen atoms, 1 chlorine atom, 2 nitrogen atoms and 3 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 × 1557.60%12.011 × 15 = 180.165 g/mol
- H Hydrogen × 216.77%1.008 × 21 = 21.168 g/mol
- Cl Chlorine × 111.33%35.45 × 1 = 35.450 g/mol
- N Nitrogen × 28.96%14.007 × 2 = 28.014 g/mol
- O Oxygen × 315.34%15.999 × 3 = 47.997 g/mol
Look up another formula
Compounds with the formula C15H21ClN2O3
Isomers we list, best known first. Open one to see its structure, properties, safety data and suppliers.
Showing 101 to 200 of 210 compounds
![(3-(Aminomethyl)piperidin-1-yl)(2,3-dihydrobenzo[b][1,4]dioxin-5-yl)methanone hydrochloride chemical structure, C15H21ClN2O3, CAS 1420861-13-7](/s/VEEXFTSQPXWVJA-UHFFFAOYSA-N.svg)
(3-(Aminomethyl)piperidin-1-yl)(2,3-dihydrobenzo[b][1,4]dioxin-5-yl)methanone hydrochloride
CAS 1420861-13-7C15H21ClN2O3
![N-(Piperidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1420995-20-5](/s/POBXPADKVQOELR-UHFFFAOYSA-N.svg)
N-(Piperidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride
CAS 1420995-20-5C15H21ClN2O3
![N-(Piperidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1420868-10-5](/s/SERGYTHVUOKPPG-UHFFFAOYSA-N.svg)
N-(Piperidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride
CAS 1420868-10-5C15H21ClN2O3
![N-(Piperidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1420820-68-3](/s/URYGFULVBLNOKM-UHFFFAOYSA-N.svg)
N-(Piperidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride
CAS 1420820-68-3C15H21ClN2O3
Methyl 1-(4-(aminomethyl)benzoyl)piperidine-4-carboxylate hydrochloride
CAS 1839957-51-5C15H21ClN2O3
![Methyl 2-chloro-5-[(4-hydroxy-2,6-dimethylpiperidin-1-yl)methyl]pyridine-3-carboxylate chemical structure, C15H21ClN2O3, CAS 2128710-36-9](/s/YUKGBWPGVXBUPV-UHFFFAOYSA-N.svg)
Methyl 2-chloro-5-[(4-hydroxy-2,6-dimethylpiperidin-1-yl)methyl]pyridine-3-carboxylate
CAS 2128710-36-9C15H21ClN2O3
tert-Butyl 4-(5-chloropyridin-3-yl)-4-hydroxypiperidine-1-carboxylate
CAS 2285473-43-8C15H21ClN2O3
![2-Chloro-N-[1-(3,5-dimethoxyphenyl)pyrrolidin-3-yl]-N-methylacetamide chemical structure, C15H21ClN2O3, CAS 2411261-83-9](/s/XNRBDVPYVXQFSS-UHFFFAOYSA-N.svg)
2-Chloro-N-[1-(3,5-dimethoxyphenyl)pyrrolidin-3-yl]-N-methylacetamide
CAS 2411261-83-9C15H21ClN2O3
![2-Chloro-N-[4-(2,2-dimethylmorpholin-4-yl)-2-methoxyphenyl]acetamide chemical structure, C15H21ClN2O3, CAS 2411237-49-3](/s/DPGORPBNCPBQMA-UHFFFAOYSA-N.svg)
2-Chloro-N-[4-(2,2-dimethylmorpholin-4-yl)-2-methoxyphenyl]acetamide
CAS 2411237-49-3C15H21ClN2O3
tert-Butyl 4-(4-chloro-2-hydroxyphenyl)piperazine-1-carboxylate
CAS 2580216-87-9C15H21ClN2O3
(S)-3-((S)-2-Amino-4-(benzyloxy)-3-oxobutyl)pyrrolidin-2-one hydrochloride
CAS 2755780-14-2C15H21ClN2O3
tert-Butyl 3-amino-4-(3-chloro-4-hydroxyphenyl)pyrrolidine-1-carboxylate
CAS 1366647-30-4C15H21ClN2O3
![(2E)-N-[2-(2-Chloro-5-hydroxyphenyl)-2-hydroxyethyl]-4-(dimethylamino)-N-methylbut-2-enamide chemical structure, C15H21ClN2O3, CAS 2411327-27-8](/s/XKSIOWRLAGOKTF-SNAWJCMRSA-N.svg)
(2E)-N-[2-(2-Chloro-5-hydroxyphenyl)-2-hydroxyethyl]-4-(dimethylamino)-N-methylbut-2-enamide
CAS 2411327-27-8C15H21ClN2O3
![2-Chloro-1-{4-[(3,4-dimethoxyphenyl)methyl]piperazin-1-yl}ethan-1-one chemical structure, C15H21ClN2O3, CAS 220832-40-6](/s/FYQNCIZMAQOHNQ-UHFFFAOYSA-N.svg)
2-Chloro-1-{4-[(3,4-dimethoxyphenyl)methyl]piperazin-1-yl}ethan-1-one
CAS 220832-40-6C15H21ClN2O3
![N~2~-[(4-Chloro-2-methylphenoxy)acetyl]-3-methylisovalinamide chemical structure, C15H21ClN2O3, CAS 115156-31-5](/s/GUJQPTLHUFHUMW-UHFFFAOYSA-N.svg)
N~2~-[(4-Chloro-2-methylphenoxy)acetyl]-3-methylisovalinamide
CAS 115156-31-5C15H21ClN2O3
![(R)-N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1421020-77-0](/s/WUAWGNHKCSXVKH-RFVHGSKJSA-N.svg)
(R)-N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride
CAS 1421020-77-0C15H21ClN2O3
![(R)-N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1421028-03-6](/s/NQLDOGDMRJFNIA-UTONKHPSSA-N.svg)
(R)-N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride
CAS 1421028-03-6C15H21ClN2O3
![N-Methyl-N-((R)-piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1421058-39-0](/s/FQNWOJNAGFXDJF-JEVWNTBDSA-N.svg)
N-Methyl-N-((R)-piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride
CAS 1421058-39-0C15H21ClN2O3
![(S)-N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1421032-61-2](/s/WUAWGNHKCSXVKH-MERQFXBCSA-N.svg)
(S)-N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride
CAS 1421032-61-2C15H21ClN2O3
![(S)-N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1421032-99-6](/s/NQLDOGDMRJFNIA-YDALLXLXSA-N.svg)
(S)-N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride
CAS 1421032-99-6C15H21ClN2O3
![N-Methyl-N-((S)-piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1421055-25-5](/s/FQNWOJNAGFXDJF-ZWUXEHSLSA-N.svg)
N-Methyl-N-((S)-piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride
CAS 1421055-25-5C15H21ClN2O3
![N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1420969-25-0](/s/WUAWGNHKCSXVKH-UHFFFAOYSA-N.svg)
N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride
CAS 1420969-25-0C15H21ClN2O3
![N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1420993-29-8](/s/NQLDOGDMRJFNIA-UHFFFAOYSA-N.svg)
N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride
CAS 1420993-29-8C15H21ClN2O3
![N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride chemical structure, C15H21ClN2O3, CAS 1420992-52-4](/s/FQNWOJNAGFXDJF-UHFFFAOYSA-N.svg)
N-Methyl-N-(piperidin-3-yl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride
CAS 1420992-52-4C15H21ClN2O3
- N-Methyl-N-(piperidin-2-ylmethyl)benzo[d][1,3]dioxole-5-carboxamide hydrochloride1420969-63-6C15H21ClN2O3
- N-Methyl-N-(pyrrolidin-2-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride1420888-66-9C15H21ClN2O3
- N-Methyl-N-(pyrrolidin-2-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride1420860-65-6C15H21ClN2O3
- N-Methyl-N-(pyrrolidin-2-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride1420835-77-3C15H21ClN2O3
- N-Methyl-N-(piperidin-3-ylmethyl)benzo[d][1,3]dioxole-5-carboxamide hydrochloride1420993-44-7C15H21ClN2O3
- N-Methyl-N-(pyrrolidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride1420861-23-9C15H21ClN2O3
- N-Methyl-N-(pyrrolidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride1420995-45-4C15H21ClN2O3
- N-Methyl-N-(pyrrolidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride1420877-80-0C15H21ClN2O3
- N-Methyl-N-(piperidin-4-ylmethyl)benzo[d][1,3]dioxole-5-carboxamide hydrochloride1420860-73-6C15H21ClN2O3
- (2,3-Dihydrobenzo[b][1,4]dioxin-2-yl)(3-(methylamino)piperidin-1-yl)methanone hydrochloride1420994-92-8C15H21ClN2O3
- N-(2-Aminocyclohexyl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride1420856-08-1C15H21ClN2O3
- N-(2-Aminocyclohexyl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride1420860-55-4C15H21ClN2O3
- N-(2-Aminocyclohexyl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride1420841-03-7C15H21ClN2O3
- (4-(Aminomethyl)piperidin-1-yl)(2,3-dihydrobenzo[b][1,4]dioxin-5-yl)methanone hydrochloride1420836-00-5C15H21ClN2O3
- N-(Piperidin-2-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride1420835-82-0C15H21ClN2O3
- N-(Piperidin-2-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride1420993-21-0C15H21ClN2O3
- N-(Piperidin-2-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride1421000-05-6C15H21ClN2O3
- N-(Piperidin-4-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-2-carboxamide hydrochloride1420868-00-3C15H21ClN2O3
- tert-Butyl N-[2-chloro-5-(morpholin-2-yl)phenyl]carbamate1895186-20-5C15H21ClN2O3
- tert-Butyl 3-(4-amino-2-chlorophenoxy)pyrrolidine-1-carboxylate2356217-63-3C15H21ClN2O3
- tert-Butyl N-[4-chloro-2-(pyrrolidin-3-yloxy)phenyl]carbamate2228368-07-6C15H21ClN2O3
- tert-Butyl N-[2-chloro-4-(morpholin-3-yl)phenyl]carbamate2228370-90-7C15H21ClN2O3
- tert-Butyl N-[4-chloro-2-(morpholin-2-yl)phenyl]carbamate2229482-69-1C15H21ClN2O3
- tert-Butyl 3-(2-chloro-4-hydroxyphenyl)piperazine-1-carboxylate2228914-36-9C15H21ClN2O3
- tert-Butyl N-[5-(1-amino-3-hydroxycyclobutyl)-2-chlorophenyl]carbamate2228355-07-3C15H21ClN2O3
- tert-Butyl 3-(3-chloro-2-hydroxyphenyl)piperazine-1-carboxylate2229225-39-0C15H21ClN2O3
- tert-Butyl N-{3-chloro-4-[(3-hydroxyazetidin-3-yl)methyl]phenyl}carbamate2228164-58-5C15H21ClN2O3
- tert-Butyl N-[2-(6-chloro-5-methylpyridin-3-yl)-1-oxopropan-2-yl]-N-methylcarbamate2228153-09-9C15H21ClN2O3
- tert-Butyl 3-(5-chloro-2-hydroxyphenyl)piperazine-1-carboxylate2228200-37-9C15H21ClN2O3
- tert-Butyl N-(4-{1-[(aminooxy)methyl]cyclopropyl}-2-chlorophenyl)carbamate2228896-37-3C15H21ClN2O3
- tert-Butyl N-[2-chloro-4-(pyrrolidin-3-yloxy)phenyl]carbamate2229379-43-3C15H21ClN2O3
- tert-Butyl N-(4-{1-[(aminooxy)methyl]cyclopropyl}-3-chlorophenyl)carbamate2229603-52-3C15H21ClN2O3
- tert-Butyl N-[1-(2-chloro-4,6-dimethylpyridin-3-yl)-2-oxoethyl]-N-methylcarbamate2228922-19-6C15H21ClN2O3
- tert-Butyl N-{5-chloro-2-[(3-methylazetidin-3-yl)oxy]phenyl}carbamate2229401-81-2C15H21ClN2O3
- tert-Butyl 2-(5-chloro-2-hydroxyphenyl)piperazine-1-carboxylate2229084-46-0C15H21ClN2O3
- tert-Butyl N-[2-(2-chloro-6-methylpyridin-4-yl)-1-oxopropan-2-yl]-N-methylcarbamate2228936-55-6C15H21ClN2O3
- tert-Butyl N-[4-(1-amino-3-hydroxycyclobutyl)-3-chlorophenyl]carbamate2229295-33-2C15H21ClN2O3
- tert-Butyl N-(2-{1-[(aminooxy)methyl]cyclopropyl}-4-chlorophenyl)carbamate2228542-64-9C15H21ClN2O3
- tert-Butyl 3-(2-chloro-6-hydroxyphenyl)piperazine-1-carboxylate2229508-05-6C15H21ClN2O3
- tert-Butyl N-{5-chloro-2-[(3-hydroxyazetidin-3-yl)methyl]phenyl}carbamate2228628-83-7C15H21ClN2O3
- tert-Butyl N-[5-chloro-2-(morpholin-3-yl)phenyl]carbamate2229431-34-7C15H21ClN2O3
- tert-Butyl 2-(2-chloro-4-hydroxyphenyl)piperazine-1-carboxylate2229538-60-5C15H21ClN2O3
- tert-Butyl N-{3-chloro-4-[(3-methylazetidin-3-yl)oxy]phenyl}carbamate2228507-28-4C15H21ClN2O3
- tert-Butyl N-[2-(2-chloro-6-methylpyridin-3-yl)-1-oxopropan-2-yl]-N-methylcarbamate2229134-04-5C15H21ClN2O3
- tert-Butyl N-[4-chloro-2-(morpholin-3-yl)phenyl]carbamate2228645-96-1C15H21ClN2O3
- tert-Butyl N-{2-chloro-5-[(3-hydroxyazetidin-3-yl)methyl]phenyl}carbamate2228987-57-1C15H21ClN2O3
- tert-Butyl N-[2-(1-amino-3-hydroxycyclobutyl)-5-chlorophenyl]carbamate2228419-15-4C15H21ClN2O3
- tert-Butyl 2-(3-chloro-4-hydroxyphenyl)piperazine-1-carboxylate2228520-37-2C15H21ClN2O3
- tert-Butyl N-[3-chloro-4-(pyrrolidin-3-yloxy)phenyl]carbamate2229550-84-7C15H21ClN2O3
- tert-Butyl 3-(3-chloro-4-hydroxyphenyl)piperazine-1-carboxylate2229490-05-3C15H21ClN2O3
- tert-Butyl N-(2-{1-[(aminooxy)methyl]cyclopropyl}-5-chlorophenyl)carbamate2229595-90-6C15H21ClN2O3
- tert-Butyl N-[2-(1-amino-3-hydroxycyclobutyl)-4-chlorophenyl]carbamate2228626-91-1C15H21ClN2O3
- tert-Butyl N-{4-chloro-3-[(3-hydroxyazetidin-3-yl)methyl]phenyl}carbamate2229368-53-8C15H21ClN2O3
- tert-Butyl N-[4-chloro-3-(morpholin-3-yl)phenyl]carbamate2229091-43-2C15H21ClN2O3
- tert-Butyl N-[4-(1-amino-3-hydroxycyclobutyl)-2-chlorophenyl]carbamate2229384-41-0C15H21ClN2O3
- tert-Butyl 2-(3-chloro-2-hydroxyphenyl)piperazine-1-carboxylate2229622-45-9C15H21ClN2O3
- tert-Butyl N-{4-chloro-3-[(3-methylazetidin-3-yl)oxy]phenyl}carbamate2228817-34-1C15H21ClN2O3
- tert-Butyl N-{4-chloro-2-[(3-methylazetidin-3-yl)oxy]phenyl}carbamate2228763-05-9C15H21ClN2O3
- tert-Butyl 2-(4-chloro-2-hydroxyphenyl)piperazine-1-carboxylate2229606-93-1C15H21ClN2O3
- tert-Butyl 4-(3-chloro-2-hydroxyphenyl)piperazine-1-carboxylate2413899-29-1C15H21ClN2O3
- tert-Butyl N-[2-(2-chloro-4,6-dimethylpyridin-3-yl)-1-oxopropan-2-yl]carbamate2229308-79-4C15H21ClN2O3
- tert-Butyl N-[3-(1-amino-3-hydroxycyclobutyl)-4-chlorophenyl]carbamate2228813-24-7C15H21ClN2O3
- tert-Butyl 3-(4-chloro-2-hydroxyphenyl)piperazine-1-carboxylate2229259-26-9C15H21ClN2O3
- tert-Butyl N-{2-chloro-4-[(3-hydroxyazetidin-3-yl)methyl]phenyl}carbamate2228236-81-3C15H21ClN2O3
- tert-Butyl 2-(2-chloro-6-hydroxyphenyl)piperazine-1-carboxylate2228627-16-3C15H21ClN2O3
- tert-Butyl N-[2-chloro-5-(morpholin-3-yl)phenyl]carbamate2229480-91-3C15H21ClN2O3
- tert-Butyl N-[5-chloro-2-(morpholin-2-yl)phenyl]carbamate2228778-97-8C15H21ClN2O3
- tert-Butyl N-[3-chloro-4-(morpholin-3-yl)phenyl]carbamate2229192-62-3C15H21ClN2O3
- tert-Butyl N-{2-chloro-4-[(3-methylazetidin-3-yl)oxy]phenyl}carbamate2228628-81-5C15H21ClN2O3
- tert-Butyl N-(5-{1-[(aminooxy)methyl]cyclopropyl}-2-chlorophenyl)carbamate2229440-99-5C15H21ClN2O3
- tert-Butyl N-[3-chloro-4-(morpholin-2-yl)phenyl]carbamate2228767-30-2C15H21ClN2O3
- tert-Butyl N-[4-chloro-3-(morpholin-2-yl)phenyl]carbamate2228448-51-7C15H21ClN2O3
- tert-Butyl N-[2-chloro-5-(pyrrolidin-3-yloxy)phenyl]carbamate2229115-32-4C15H21ClN2O3
- tert-Butyl N-(3-{1-[(aminooxy)methyl]cyclopropyl}-4-chlorophenyl)carbamate2228509-84-8C15H21ClN2O3
- tert-Butyl N-[4-chloro-3-(pyrrolidin-3-yloxy)phenyl]carbamate2229516-85-0C15H21ClN2O3
- Ethyl 3-chloro-4-{[2-(morpholin-4-yl)ethyl]amino}benzoate2639427-09-9C15H21ClN2O3
Frequently asked questions
What is the molar mass of C15H21ClN2O3?
The molar mass of C15H21ClN2O3 is 312.79 g/mol, calculated from standard atomic weights for 15 carbon atoms, 21 hydrogen atoms, 1 chlorine atom, 2 nitrogen atoms and 3 oxygen atoms. The monoisotopic mass is 312.1241 Da.
How many compounds have the formula C15H21ClN2O3?
CompoundList lists 210 compounds with the molecular formula C15H21ClN2O3, including (3-(Aminomethyl)piperidin-1-yl)(2,3-dihydrobenzo[b][1,4]dioxin-5-yl)methanone hydrochloride, N-(Piperidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-5-carboxamide hydrochloride, N-(Piperidin-3-ylmethyl)-2,3-dihydrobenzo[b][1,4]dioxine-6-carboxamide hydrochloride. 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 C15H21ClN2O3?
C15H21ClN2O3 has a degree of unsaturation of 6. 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.