Contains introduction to prostaglandins and their biological importance, occurrence and general structure

1. Mr. Pruthviraj . K
Department of studies and research in Organic chemistry
Tumkur University , Tumkur
PROSTAGLANDINS

2. The prostaglandins are a group of naturally occuring unsaturated,
hydroxy or hydroxyketo fatty acids.Von Euler believing that the bioactive
substance was produced bye the prostate glands coined the term
prostaglandin in 1935.
The prostaglandins are c-20 carboxylic acids with a cyclopentane ring.
The cyclopentane ring with two side chains contains usually a beta- keto
or an enone or two hydroxyl functionalities. The side chains are
unsaturated with one, two or three double bonds. A common feature of
all bioactive prostaglandins is a alpha-hydroxyl group at c-15, examples
are prostaglandins E1 & prostaglandins A2 .
PGE1 PGA2
PROSTAGLANDINS:-

3. Prostaglandin was first isolated from human semen and the from
sheep sperm or vesicular glands of male sheep. Some of the primary
prostaglandins were found to exist in various tissue, eg lungs, iris,
brains, thymus, pancreas, kidney etc. Recently, PGE1 & other
derivatives have been isolated from soft coral, plexaura homomallar.
NOMENCLATURE:-
The parent skeleton of prostaglandins is the fully saturated
cyclopentane C-20 hydrocarbon ‘prostane’& the related carboxylic
acid skeleton is called ‘prostanoic acid’.
Prostane Prostanoic

4. in to several families designated as PGA,PGB,PGC,PGE,PGF
and PGH. This is based on the nature of the functionalites in
the five membered ring. The letter E in PGE refers to the fact
that these compounds are more soluble in ether.

5. The compounds with greater solubility in phosphine buffer are
called PGFs . The letters A & B in PGA & OGB refer the
compounds resulting from the treatment of PGE with acid and base
respectively. The chemical relation b/w PGA,PGB,PGE & PGF are
given in below. The number of double bond in molecule present b/w
c-13 and c-14 as ‘trans’ double bond. PGE2 denotes on additional
double bond b/w C-5 & C-6 & PGF3 denotes on additional double
bond b/w C-17 & C-18 .
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6.  Prostaglandins control carbohydrate and lipid metabolism.
 Prostaglandins act as local modulator of cell functions.
 Prostaglandins play a virtual role in the cardiovascular, renal
functions, reproductive nervous, digestive, haemostabic
respiratory and regulation of endocrine functions.
 If metabolism and production of prostaglandin is changed this
may cause hypertension, pain, fever, bronchial asthma,
inflammation and ulcer formation.
 Effect of prostaglandin is affected in the presenmce of
antipyretic, analgesic and anti- inflammatory drugs. These
drugs inhibit the biosynthesis of prostaglandin. For example
aspirin.
Physiological Role of Prostaglandins

7. 1) PGE1 :- If dilates the blood vessels, so used for the treatment of
hypertension and congestive heat failure. It acts on cardiovascular
system.
2) PGE1 , E2 , A :- Acts on gastrointestinal system. It inhibit acid
secretion. Stimulate mucous secretion increased motility.
3) PGE2 :- Acts on renal system. It regulates renal blood flow. It is
used for treatment of impaired renal function.
4) PGE1 , E2 :- Acts on respiratory system. It relaxes bronchial tissue.
It is used for the treatment of asthama & bronchonstriction,
vasodilation.
5) PGF2ά :-PGE2 acts on reproductive organs. It stimulates uterine. It
is used for treatment of contraction of pregnant, uterus, contraction
of pregnant or nonpregnant uterus. Iysis can corpus luteum.
Biological properties of prostaglandins :-

8. Prostaglandins are powerful locally acting
vasodilators and inhibit the aggregation of blood
platelets. Through their role in vasodilation,
prostaglandins are also involved in inflammation.
They are synthesized in the walls of blood vessels
and serve the physiological function of prevelating
needless dot formation , as well as regulating the
contraction of smooth muscle tissue.

9.  Organic chemistry of natural products – volume-2 ,Gurdeeo R ,
Chatwal- Edited by M. ARORA.
 Natural products chemistry – Jagadamba Singh.
 Chemistry of natural products – Jain sahai.