introduction and Nomenclature of steroids.pptx

Content :Introduction
Nomenclature
Present in Animal, plants.
Basic nucleus – Cyclopentaperhydrophenanthrene.
Present in Animal, plants.
Basic nucleus – Cyclopentaperhydrophenanthrene. Consist of 4 rings A, B, C & D.
Completely saturated derivative.
A, B, C = Cyclohexane
D= Cyclopentane


Basic Skeleton= 17 C
Numbering Start from A– B– C–D.
Additional carbons present at C10 and C13.
Alkyl substituents on C17
Methyl groups at C10 & C13 = Angular methyl groups.
Nomenclature:
Configuration at:
C5 =Dotted lines = α (alpha)=Trans
C13=Solid lines = β (beta) =Cis
No configuration = wave LinesDouble bond ane = ene
1 double bond =ene
2 double bond= diene
3 Double Bond = triene

You can simply
Represent (=) by giving
numbering of that
position. Double bond position
denoted by Δ (Delta).
C4=C5 –--Δ 4
C5= C10 ----Δ 5(10)

If 3 membered ring =
Prefix Cyclo with
Respective position no.
Compounds with
5 α Cholestane = Allo series[fig.1]
5 β Cholestane = normal seriesAny enlargement in ring then capital letter
of ring with ‘Homo’.
Eg.A-homo , B-homo etc

Methyl group is missing = prefix ‘nor’

Methyl group at C13 and C10 are always
in beta configurations so no need to write
it in name of steroids.
Substituent position no. should be write.

1. Nomenclature of Steroids Presented by Divya Ashok Dhule M.Pharm .(Pharmaceutical Chemistry) 1 st year Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur university, Nagpur

2. Content : Introduction Nomenclature

3. Introduction : Present in Animal, plants. Basic nucleus – Cyclopentaperhydrophenanthrene . Hydrog enation Perhydrophenanthrene

4. Consist of 4 rings A, B, C & D. Completely saturated derivative. A, B, C = Cyclohexane D= Cyclopentane Basic Skeleton= 17 C Numbering Start from A– B– C–D. Additional carbons present at C10 and C13. Alkyl substituents on C17 Methyl groups at C10 & C13 = Angular methyl groups. Groupgroups

5. Nomenclature: Configuration at: C5 =Dotted lines = α (alpha)=Trans C13=Solid lines = β (beta) =Cis No configuration = wave Lines 5- α Androstane

6. Double bond ane = ene 1 double bond = ene 2 double bond= diene 3 Double Bond = triene You can simply Represent (=) by giving numbering of that position. (17β)-estra-1,3,5(10)-triene-3,17-diol

7. Double bond position denoted by Δ (Delta).
C4=C5 –--Δ 4
C5= C10 ----Δ 5(10) If 3 membered ring = Prefix Cyclo with Respective position no.

8. Compounds with 5 α Cholestane = Allo series[fig.1] 5 β Cholestane = normal series Fig. 1 5 α Cholestane Fig. 2 5 β Cholestane

9. Any enlargement in ring then capital letter of ring with ‘ Homo’. Eg. A -homo , B-homo etc Methyl group is missing = prefix ‘nor’ Methyl group at C13 and C10 are always in beta configurations so no need to write it in name of steroids. Substituent position no. should be write. Nor Androsterone

10. Ring fission or ring broken = prefix is ‘Seco'

11. Examples of steroids:

12. Reference : V. Alagarsamy , Pharmaceutical chemistry of Natural products, Steroids, vol 2 , 2012 pg no. 250 -291