| 1/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, not substituted in position 17 beta by a carbon atom, e.g. oestrane, androstane |
| 3/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, substituted in position 17 beta by one carbon atom |
| 5/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, substituted in position 17 beta by a chain of two carbon atoms, e.g. pregnane, and substituted in position 21 by only one singly bound oxygen atom |
| 7/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, substituted in position 17 beta by a chain of two carbon atoms (C07J 5/00 takes precedence) |
| 9/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, substituted in position 17 beta by a chain of more than two carbon atoms, e.g. cholane, cholestane, coprostane |
| 11/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, not substituted in position 3 |
| 13/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, having a carbon-to-carbon double bond from or to position 17 |
| 15/00 | Stereochemically pure steroids containing carbon, hydrogen, halogen, or oxygen, having a partially or totally inverted skeleton, e.g. retrosteroids, L-isomers |
| 17/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, having an oxygen-containing hetero ring not condensed with the cyclopenta[a]hydrophenanthrene skeleton |
| 19/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, substituted in position 17 by a lactone ring |
| 21/00 | Normal steroids containing carbon, hydrogen, halogen, or oxygen, having an oxygen-containing hetero ring spiro-condensed with the cyclopenta[a]hydrophenanthrene skeleton |
| 31/00 | Normal steroids containing one or more sulfur atoms not belonging to a hetero ring |
| 33/00 | Normal steroids having a sulfur-containing hetero ring spiro-condensed or not condensed with the cyclopenta[a]hydrophenanthrene skeleton |
| 41/00 | Normal steroids containing one or more nitrogen atoms not belonging to a hetero ring |
| 43/00 | Normal steroids having a nitrogen-containing hetero ring spiro-condensed or not condensed with the cyclopenta[a]hydrophenanthrene skeleton |
| 51/00 | Normal steroids with unmodified cyclopenta[a]hydrophenanthrene skeleton not provided for in groups C07J 1/00-C07J 43/00 |
| 53/00 | Steroids in which the cyclopenta[a]hydrophenanthrene skeleton has been modified by condensation with carbocyclic rings or by formation of an additional ring by means of a direct link between two ring carbon atoms |
| 61/00 | Steroids in which the cyclopenta[a]hydrophenanthrene skeleton has been modified by contraction of only one ring by one or two atoms |
| 63/00 | Steroids in which the cyclopenta[a]hydrophenanthrene skeleton has been modified by expansion of only one ring by one or two atoms |
| 65/00 | Steroids in which the cyclopenta[a]hydrophenanthrene skeleton has been modified by contraction of two rings, each by one atom |