Page 21 - Org 3 theoritical book 2024-25

Clinical Pharmacy PharmD - 2024/2025 Level 2 Pharmaceutical Organic Chemistry-3 (PC 305)
However, the old suffixes are still commonly used and will be generally applied

here.

Rule 3:

The state of hydrogenation is indicated:

• In the suffix according to the above tables, or

• By the prefixes dihydro, tetrahydro,. etc., or

• By prefixing the name of the parent unsaturated compound with the

symbol H preceded by a number indicating the position of saturation.

Rule 4:

a) Numbering of the rings starts with the heteroatom and proceeds around the ring so

as to give substituents (or other heteroatoms) the lowest numbers possible.